motion monitor mm-25 - hitachi rail · oscillator and changes in signal strength due to train...

June, 1983 WP0168A A-6/83-250-2496-l

PRINTED IN USA

SERVICE MANUAL 6252

MOTION MONITOR MM-25

UNION SWITCH & SIGNAL DIVISION AMERICAN STANDARD INC./ SWISSVALE, PA 15218

Section

I

II

III

IV

v

VI

VII

UNION SWITCH Ii SIGNAL m

GENERAL INFORMATION 1.1 PURPOSE OF EQUIPMENT 1.2 ISLAND CIRCUIT

CONTENTS

1.3 OPERATIONING PARAMETERS 1 .4 DESCRIPTION . 1.5 SYSTEM.PRINTED CIRCUIT BOARDS

1 ;5. 1 · · Signal Board 1.5.2 .D~tectorBoard 1 .5. 3 Island Board.

1.6 EQUIPMENT SPECIFICATIONS 1.6.1 Electrical 1.6.2 Mechanical

APPLICATION 2.1 GENERAL RULES FOR APPLYING ANY MOTION DETECTION DEVICE 2.2 OPERATIONAL CONSIDERATIONS

2.2.1 Track Ballast 2.2.2 Stabilization of Track Characteristics Through

Shunts 2.2.3 Types of Shunts

2.3 ISLAND ZONE DEFINITION 2.3.1 Configuration of Island Track Connections

2.4 PARALLEL TRACK OPERATION 2.5 r-K)TION MONITOR FREQUENCY SELECTION 2.5.1 Basic Connections

INSTALLATION AND ADJUSTMENTS 3 .1 MCXJNTING 3.2 EXTERNAL EQUIPMENT 3.3 CONNECTIONS 3.4 TRACK STRAP 3.5 ADJUSTMENT PROCEDURE OPERATION 4.1 BASIC COMPONENTS 4.2 TRANSMITTERS 4.3 MOTION RECEIVER AND DIFFERENTIATOR 4.4 ISLAND RECEIVER 4.5 VITAL GATE LOGIC AND RELAY DRIVER FUNCTIONAL DESCRIPTION 5. 1 SIGNAL BOARD 5.2 DETECTOR BOARD 5.3 ISLAND BOARD FIELD MAINTENANCE 6.1 FUSE REPLACEMENT 6.2 FIELD EQUIPMENT AND TESTS 6.3 PERIODIC MAINTENANCE SHOP MAINTENANCE

1-1 1-1 1-1 1-2 1-2 1-3 1-3 1-3 1-4 1-4 1-4 1-4 2-1 2-1 2-1 2-1

2-2 2-2 2-3 2-3 2-3 2-7 2-8 3-1 3-1 3-1 3-2 3-3 3-3 4-1 4-1 4-1 4-1 4-1 4-3 5-1 5-1 5-2 5-7 6-1 6-1 6-1 6-2 7-1

APPENDIX A - PARTS LIST

i

m UNION SWITCH & SIGNAL

Contents Cont'd.

Table I Operating Parameters

Figures

2-1 2-2 2-3 2-4 2-5

2-6 2-7 3-1 4-1 5-1 5-2 5-3 5-4

A-1

Typical MM-25 Application Frequency Selection Chart for 3 ohms/1000' Frequency Selectipn Chart for. 5 ohms/1000' Frequency Selection Chart for 10 ohms/1000' External Wiring and Connectibns for a Simple MM-25 Installation External Wiring With Single AFO Wrap around External Wiring With Dual AFO Wrap around Voltage/Approach Length Chart Motion Monitor Block Diagram Signal Board Block Diagram MM-25 Circuit Diagram Detector Board Block Diagram Island Board Block Diagram

MM-25 Parts Assembly

ii

1-2

2-2 2-4 2-5 2-6

2-9/2-10 2-11/2-12 2-13/2-14 3-6 4-2 5-2 5-3/5-4 5-5 5-8

A-3/A-4

1.1 PURPOSE OF EQUIPMENT

SECTION I GENERAL INFORMATION

UNION SWITCH & SIGNAL

The MM-25 Motion Monitor is a solid state track overlay device which is designed to detect train movements toward a highway crossing. The Motion Monitor detects train motion by continuously measuring track circuit status. A constant current is fed into the rails adjacent to the highway at the crossing. This current develops a rail-to-rail voltage proportional to the track circuit impedance. As a train proceeds toward the crossing, the moving shunt effect of the train's leading wheels decreases the impedance of the track circuit at the feed point (crossing) thus reducing the rail-to-rail voltage. The rate at which the impedance decreases is related to train speed and position within the warning zone along with several other factors including, but not limited to, length of warning zone, track rail impedance, and ballast resistance. Within the initial portions of the approach, the distance from the highway crossing to the point of initial detection is directly proportional to train speed; i.e., the greater the speed the greater the distance. A high - level detector provides protection against broken bonds in the approach zones.

When a train operating within the MM-25's approach limits has stopped or reverses, moving away from the crossing, the Motion Monitor will clear the crossing, permitting automotive traffic to resume. Likewise, the highway crossing is cleared after a train proceeds through the crossing and has reached to the point where the last car's wheels have cleared the island circuit.

1.2 ISLAND

The Motion Monitor system includes a built in circuit for the island zone. An internal receiver, which is connected to the rails on the opposite side of the highway from the track feed, continuously monitors the rail to rail voltage at that point. If a train shunt occurs in the vicinity of the crossing, the receiver input voltage will fall below the island receiver's threshold, thus detecting the presence of a train much as in a conventional AFO circuit. Receiver sensitivity is adjustable to accommodate a wide range of applications.

6252, p. 1-1


1.3 OPERATING PARAMETERS

In general, the Motion Monitor will perform over the ranges of parameters indicated in Table I although not all extreme limits may exist concurrently. Typical application data is covered in Section II.

Table I. Operating Parameters

Motion Sensing

Warning Zone Warning Times Speed Range

Track Characteristics

Ballast Shunting Sensitivity

Response Time

Detection Clearing

Island Protection

Length Ring by

600' min to 3200' max. (183M to 975M) 6 to 39 seconds (adjustable) 4 MPH to 100 MPH (6.4 MPH to 160 MPH)

1. 0 ohm/ 1000 ft. to "infinite" 0.0 to 0.06 ohms

0.1 to 0.5 seconds Dependent on timer setting (6-36 seconds)

Maximum Car Span to 300 feet (911M) 3 to 15 ft. (0.9M to 4.6M)

NOTE

Operating Characteristics depend upon the sum total effects of all system parameters. Therefore, the above values may not all apply simultaneously.

1.4 DESCRIPTION

The components of the MM-25 are housed in a sheet metal case with AAR terminals provided for external connections. Three locking adjustments are conveniently located on the front panel and provide for the TIME adjustment (factory ajusted to 20 seconds), the island SENSITIVITY adjustment, and the high-level detector adjustment. A 3 amp. SLO-BLO fuse for circuit protection and three LED indicators provide a quick check of the condition of the unit. With no train shunting the rails of the track circuit and no track· faults (such as broken bonds), the ISLAND LED will be illuminated and the MOD CHECK LED will alternate on and off at a 5 Hz rate. The TRACK FAULT LED will be off unless there has been an intermittent track problem, in which case a memory circuit will cause the LED to stay on even if the track fault condition corrects itself. Pushing the TEST/RESET pushbutton tests the high-level detector circuitry and TRACK FAULT LED, while releasing it resets the track fault memory circuit. Three printed circuit boards, the signal board, the'

6252, p. 1-2


detector board, and the Island Board, contain the remainder of the components. In some MM-25 units the high-level detector circuitry is on a fourth printed circuit board rather than on the detector board.

1.5 SYSTEM PRINTED CIRCUIT BOARDS (PCB)

The Motion Monitor MM-25 contains three printed circuit boards: signal board, detector board and island board.

1.5.1 Signal Board

The Signal Board consists of the following:

a. A vital, level controlled transmitter oscillator that establishes the frequency of the unit. These frequencies are: 207 Hz, 230 Hz, 390 Hz, 405 Hz, 570 Hz and 630 Hz.

b. Preamplifier with factory adjusted gain, fed from the transmitter oscillator, provides the drive to the power amplifier, and controls the output current.

c. Transmitter constant current power amplifier with one output lead, coupled to the rail by means of a series tuned track filter.

d. A low frequency modulation transformer coupled to a 5 Hz multivibrator that provides the self check capability.

e. Motion receiver tuned input circuit feeding a power amplifier and voltage transformer to provide input to the differentiator, no-motion receding train oscillator, and the vital gate.

1.5.2 Detector Board

The Detector Board consists of the following:

a. Voltage doubler and vital filter feeding the differentiating capacitor, which couples the self-check modulation signal to an oscillator and changes in signal strength due to train motion.

b. Oscillator which generates an output when there is no motion (train stopped) or when a receding train is detected.

c. Vital gates •

d. Low frequency detector, amplifier and rectifier.

e. Island relay and motion monitor relay drivers.

f. Timer circuit.

g. High-level detector circuit.

6252, p. 1-3


Island Board

The Island Board consists of the following:

a. The transmitter circuit consisting of a carrier and a modulation oscillator driving a tm.ity gain amplifier and the high pass filter out put stage.

b. The receiver input circuit consisting of a high Q-bandpass filter, and a demodulator driving an amplifier which, in turn, drives a negative DC maker to power an oscillator stage.

1.6 EQUIPMENT SPECIFICATIONS

1.6.1 Electrical

Input:

Current Drain:

Rail Current:

Frequency ..:!::. 1%

Modulation Frequency:

Output Loads:

Motion Monitor Relays Island Relays

Temperature Range:

Track Lead Resistance:

Transmitter Receiver

9.5 to 16.2 Vdc (0.5V P-P maximum Ripple*)

207 & 230 Hz - 1.9 Amps (nominal) 390 & 405 Hz - 1.4 Amps (nominal) 570 & 630 Hz - 1.2 Amps (nominal)

207 & 230 Hz - . 1 • 0 Amps 390 & 405 Hz - 0.5 Amps 570 & 630 Hz - 1.33 Amps

Motion Monitor 207 & 230 Hz 390 & 405 Hz 570 & 630 Hz

52 Hz + 5 Hz

Vital Relays

Island 12.28 KHz 15.00 KHz 20.00 KHz

400 Ohms (PN-150BH) 400 Ohms (PN-150BH), (PN-150B)

-400F to +1600F (-400C to +700C)

No more than 0.15 Ohms total No more tha.~ 0.50 Ohms total

*If this value is greater than 0.5V p-p, a surge ripple filter must be used.

1.6.2 Mechanical

Height: 10-1/4 inches (26 cm) Depth: 6 inches (15.2 cm) Length: 12 inches (30.5 cm)

The case may be shelf, wall or rack mounted.

6252, p. 1-4

2.1 GENER.AL RULES

SECTION II APPLICATION


The following considerations should be kept in mind when applying a motion detection device (See Figure 2-1).

Double bonding within the approach limits of highway crossings is recommended to improve the margin of protection against improper operation due to a single high resistance bond connection.

The Track Coupling Unit Tuned Shunts should be used if there are any insulated joints within the effective limits of the motion monitoring track circuit. However, there is no indication given in the event that one of these units becomes disconnected. For this shortcoming, similar to that of the previously mentioned bonding, the only solution is to use continuous rail through the approach and island circuits.

Two sets of insulated joints should be located between motion detection devices operating at the same frequency on the same track.

For any motion detection devices, certain conditions of broken rail can negate train detection while train movements are in progress. Therefore, inspection procedures should be exercised to insure the integrity of the rail circuit, including bond wires, joints, etc.

In no case should any cars be left standing on a highway crossing equipped with a motion detection device while switching is being perfonned unless operating rules require a flagman during such an operation.

2.2 OPERATIONAL CONSIDERATIONS

Optimum results from the Motion Monitor can only be obtained through an understanding of the following factors involved and how these factors can be manipulated to the users best advantage.

2.2.1 Track Ballast

Changes in track ballast resistance will have an effect on Motion Monitor operation. Track circuit stabilization is suggested as a means of dealing with the ballast resistance problem.

Some of the effects of ballast resistance changes are:

a. Decrease in effective approach distance.

b. Narrowing of speed range applicable for a given warning time.

fl252, p. 2-1


TUNED SHUNT

B

N

TRANSMITTER CONNECTIONS

FILTER

5 II

ll

J L

7 17 15

MOTION

MONITOR 10

* OPTIONAL

IR* MMR

Figure 2-1. Typical MM-25 Installation

c. Decrease in minimum warning time.

d. Lengthening of effective island zone.

TUNED SHUNT

The Motion Monitor is designed to perform satisfactorily with track ballast of 3 ohms/1,000 ft. to infinite ballast resistance. However, when the approach distance is short, it will operate under some conditions with track ballasts as low as 1 ohm/1,000 feet.

2.2.2 Stabilization of Track Characteristics Through Shunts

Rail to rail shunts are imperative in continuous rail areas and must be applied at the extremes of the warning zone. The shunts enhance performance particularly under various environmental conditions and minimize variations in the following:

a. Effective warning distance. b. Speed range applicable for a given warning time. c • Maximum warning time. d. Length of effective island zone.

6252, p. 2-2

UNION SWITCH & SIGNAL m 2.2.3 Types of Shunts

These shunts may be one of two types depending upon whether or not other signals co-exist on the rails as follows:

a. Hardwire or zero Ohm impedance shunts may be used where such devices will not disrupt operation of other rail carried signals.

b. Tuned, series resonant shunts are used in applications where de signals and/or ac signals of ther frequencies are using the rails concurrent with the Motion Monitor.

It is imperative that rail-to-rail shunts as described previously must be placed at the desired distance from the crossing (see Figure 2-1).

In placing these shunts, care must be exercised to place them within the limits defined in the Frequency Selection Charts, Figures 2-2, 2-3, and 2-4. Unsynmetrical arrangements of the warning zone tend to de-sensitize the Motion Monitor; however, performance remains generally within acceptable limits for configurations having up to 1.3: 1 unbalance.

Rail-to-rail shunts should be located appropriately in consideration of all railroad operating conditions. Deviations from limiting conditions should be covered by appropriate railroad operating rules.

2.3 ISLAND ZONE DEFINITION

The chief purpose of the island circuit is to detect occupancy of the crossing by either stopped or very slow speed rail traffic.

2.3.1 Configuration of Island Track Connections

The track feed leads are connected to the rails adjacent to the highway. A second pair of track leads for the island receiver are connected to the rails on the opposite side of the highway. The minimum distance between the two pairs of leads, in addition to spanning the highway, should not be less than the maximum inner wheel span of the railroad cars using the crossing.

2.4 PARALLEL TRACK OPERATION

Where two parallel tracks are to be equipped with Motion Monitors, different frequencies must be used on each adjacent track to avoid mutual interference.

62~2, p. 2-3

O'I I\) IJ1 I\) .. 'O . I\) I ~

MAX APPROACH SPEED (MPH)

100 t 90

80 I

70

60

50

40

30

20

10

~~G ~"?>-¢

~c· ~I;)~

/ /

Approach zone bench mark for long track or short track strap ag,lication. To the left of point a put shorting strap in short strap position. To the right of point a put shorting strap in long strap position. When tuned shunts are used, bench mark "a" might need to be shifted to the left an additional 10%.

207, 230 Hz Units __ - ~ ,--- --- -----390, 405 Hz onfts

None

... fa ,-._ .. 570, 630 Hz Un~s

None J a

500 1000 1500 2000 2500 3000 3500 00

EFFECTIVE LENGTH OF APPROACH ZONE - (FEET)

Figure 2-2. Frequency Selection Chart For 3 Ohne/1000'

EE c z 0 z I =i

,O :x: IIJI CII

i5 z I

> r

"' I\) \J1 I\) ... "d . I\) I

\J1

MAX. APPROACH SPEED (MPH)

I 100

90

80

70

60

50

40

30

2.0

10

500

~c· ',<::) ~

~~6 ~~~~ .

AR;)roach zone bench mark for long track or short track strap a:i;plication. To the left of point a put shorting strap in short strap position. To the right of point a :put shorting strap in long strap position. When tuned shunts are used, bench mark "a" might need to be shifted to the left an additional 10%.

207, 230 Hz Units 1111 ,.. fa

390, 405 Hz Units .., ,.. fa 4 570, 630 Hz Units .,

+ a

1000 1500 2000 2500 3000 3500 4000


Figure 2-3. Frequency Selection Chart For 5 0hDS11000'

c z 0 z I ~ :c 11!1 en a z > ....

EB

°' I\) \J1 I\) ... 'Cl . I\) I

°'

MAX APPROACH SPEED (MPH)

100 r 90 r 80

70

60

50

40

30

20

10

I 7

I /

e,· ~~

,.,,c::i

4~ a: ,g;.~~

~~

....<iii I a

Approach zone bench mark for long track or short track strap awlication. 'lb the left of point a put shorting strap in short strap position. To the right of point a put shorting strap in long strap position. When tuned shunts are used, bench mark "a" might need to be shifted to the left an additional 10%.

207, 230 Hz Units ._,.. None

,.. 390, .405 Hz Units..,

+ a .. .. 570, 630 Hz Unit,-

None + a

500 1000 1500 2000 2500 3000 3500 4000 4500 5000


Figure 2-4. Frequency Selection Chart For 10 Ohns/1000'

EB c z 6 z I ::j 0 :c Rt en i5 z )I, I"'


2.5 MOTION MONITOR FREQUENCY SELECTION

For various reasons it is not possible to establish rules that will show operation under actual field conditions. The following is supplied as a guideline for frequency selection ••

The six available motion monitor frequencies are arranged into 2 groups as shown below;

Group 1

207 Hz 390 Hz 570 Hz

Group 2

230 Hz 405 Hz 630 Hz

Do not repeat the same frequency on the same track unless adjacent units are separated by two insulated joints or are at least eight miles apart.

Do not mix frequencies of both groups on one track unless adjacent units are separated by at least one insulated joint or are at least five miles apart.

As stated previously in Section 2.2.1, it is necessary to determine the minimum track ballast resistance encountered at the particular highway crossing. To determine the applicable frequencies for a given installation, determine the maximum approach speed of rail traffic and the desired warning time. Select the applicable chart (Figure 2-2 for 3 ohms, Figure 2-3 for 5 ohms, and Figure 2-4 for 10 ohms) according to the minimum track ballast resistance to be encountered., Where the horizontal speed line intersects the diagonal warning time line, look down to the horizontal scale to determine the minimum length of the approach zone. The permissible operating frequencies may be read by referring to the area in which the speed and time line intersect.

From these charts it can be seen that the operating frequency, channel separation or number of channels within a given range, the maximum detectable range, minimum ballast, and the warning time are all interrelated. The following formula may be used as a guide to detection range and warning time.

As a general rule of thumb:

L=70~

Where L = Detecting range (ft.) f = Frequency (Hz) b = Ballast (ohms/1000 ft.)

EXAMPLE: At 3 ohm ballast and 207 Hz L = 2665 ft.

6252., p. 2-7


Warning Time can be defined by: T = L/V

Where T = Warning Time (Sec.) V = Velocity (ft./sec.) L = Initial Detection (Ft.)

EXAMPIE: For an initial detection at 2, 665 ft. and 60 MPH trains (88 feet/sec.), the warning time would be about 30 sec.

2.5.1 Basic Connections

Figure 2-5 illustrates the external wiring and connections to the MM-25 for a simple installation., This Figure illustrates a basic system with the power supply relay and track connections that are necessary. The MM-25 can be employed in a variety of ways, including interlocking with wrap around de or audio. See Figures 2-6 and 2-7. The MM-25 offers flexibility to meet the system needs as determined by the customer by following these basic guidelines.

6252, p. 2-8

SHUNT

• BX120A

~ NX120A

STRAP: T1PT0+3P

2P TO 4P

ISLAND RECEIVER

CONNECTIONS

@

#

r----,

J

812

#10

N11

#10

TO --,#.,....9--1.:.,-.-;;..._.;;.;;..._-1-- I BXl'20A

12~~:f #14 SOURCE I

NX120A

POWER ON

LIGHT

#9

BXl20A

#14

NXl20A #14

GROUND

I #14 L-----' 120V LINE

TERMINAL ....---#-

6----- TO GROUND BUSS

L YT

UNION SWITCH & SIGNAL m TRANSMITTER CONNECTIONS

SHUNT

812

N12

ITEM DESCRIPTION

1 MOTION MONITOR, MM-25

2 RELAY, MOTION MONITOR TYPE PN-150BH

3 RELAY, CROSSING TYPE DN-11

4 RECTIFIER, 13.5 voe, 4.4 AMP TYPE CCR-4

5 SURGE RIPPLE FILTER

6 CIRCUIT BREAKER, 6 AMP 7 USG LIGHTNING ARRESTER

HIGH VOLTAGE

8 USG LIGHTNING ARRESTER LOW VOLTAGE

9 TEST CLIP

10 LIGHT, POWER ON

11 BATTERY, 6 CELLS LEAD

12 RELAY, ISLAND

13 MOUNTING BASE, IR

14 MOUNTING BASE, MMR

Figure 2-5. External Wiring and Connections for a Simple MM-25 Installation

6252, p. 2-9/2-10

APP!. ICATl(l'l NOT[S

THIS TYPIC.AL IS l"ITE"IOED TO SHO'N O"ILY THE CIRCUIT CQ"IFIGURATIO,_,

"'IECE!'SARY TO OBTAl"l'"XR .. OPERATIOl'\I WHE"l MOTIO"l MO'lltTOR EQUIPMENT IS E'MPLOYEO. AOOITIO"i,'L CIRCU'T!'= TO BE ADDEO AS REQUIRED TO COI\ITROL SPECIFIC WAA,..l"IG

DEVICES U~EO. FOP AOOITlQ"-1,At. ,APrLtC"*'TIO°'l DETAIL! A",jQ t'IIFORMATIO..,, RELATIVE TO ~1"-ITE"IA"IC"E l"lSTRUCTIO"lS• REF[R TO SfPVlt[ MA,..UAL 6089 FOR fvWl-21 ,Ml{'I SERVICE M.A"IUAL 59')b FOR ... FO J::t. FOR .-,PPLICATJO",j~ l"I T(RR1TORY l'IIVOLVl.,,G COOED RAIL CURRPH! OR OTHER ~P[CIAL APPLIC,'TJ0"45, C0"'4SULT THf HIGHWAY

CROSSl'IIG SYSTEMS f,_,.Gl'IIEERl'\IG SECT ION, U.S. & S. DIV. #ABCO.

• = TWISTED PAIR - THREE TUR~/FOOT ( IF EXTRA WIRE LE~TH IS PROVIDED

/1.G,'1..,ST FUTURE n.-.1s1"4G OF TRACK STRUCTURE OR OTHER - !'lQ. !ml. £2..!!s.) &.= .AFTER OETERMl"Jl"IG THE REQUIRED APPROACH LIMITS, REFER TO THE APPROPRIATE FREQUE"JCY SELECT ION CH.ART (FOR Ti-IE PREVAIL1"41G TRACK BALLAST VALUE) l"f SERVICE MANUAL 6089 FOR hN-21 ANO SERVICE MANUAL 5906 FOR AFO II, ANO CHOOSE THE IAll-20/AFO ll FREQUE"JCY 1'401CATEO. NOT£ TH.-.T TWO SETS OF JOl"JTS SHOULD BE USED TO SEPARATE MOTION MONITOR DEVICES OPEAAT ING ON THE SM}(' FAEQUE"'ICY ON TH£ SAME TRACK. ALSO WHERE ':'WO PAAALt..[L TRAC'KS ARE TO BE EQUIPPED WtTH MOTIO"J MONITORS, OIFFERE"fT FREQUENC 1£5 MUST BE USED 0.. EACH ADJACE"4T TRACK TO AVOID MUTUAL l"JTtAFl!RE"JCE. ALSO BE GOVERt.lEO BY RULES REGAROl"1G AFO O FREQUE,.,CY ALLOCAT 10,,,. &.= USG SHU ... T ARRESTOR WITH TERM1"4AL BLOCK Nl14266t WITHOUT TERM1"4AL BLOCK "11314215. &= USG SERIES ARRESTOR WITH TEAMlt\lAL BLOCK "113279119J WITHOUT TEAMl"JAL

~ BLOCK ..,327913. t.:.::;.= TRACK LEAD RESISTANCE IS "OT ro EXCEEO o.15W F'QP TRJ."JSM. MID ?.5W fOP

RECv. MM-21 TRA"4SM. LE,._DS (TERMS 5 \ 7) SH,'.LL ALWAY~ Bf TH[ ~ ~~"! TO I SLANO zot« FROM CASE. .&.= TRACK STRAP ADJUSTMENT, RtF'ER TO THIS SU8J£CT AS COVERED BY MM-20

A SfJtVIC[ ~'«JAL 6019. ~- Pti-lSOBH RELAY IF'&,IF,18 STD·, 400(0, NJ22511-00lJ BASE "1)49904.

~ PN-1508 RELAY GFB STD., 400(1)1

NJ2U00-901 J BASE ,.,,U42&6.

~ PN-ISOBH RELAY IFB,IF,IB STO., 4000), NJUSl~-oo,, BASE fil4tt04.

b INTER .. AL TIMl"IG CIRCUIT. ADJUSTABLE FROM g .. Jg SECONDS. DELAYS. PICK-UP /:).,. OF' 1.wR RELAY AE:LAT IVE TO THE PRED£TERMIP«D SET TIME. ~= f'OR ISLAND ZOPC DEf'l"IITION, R[f'fR TO THiS SUBJECT AS COVERED IV 161-21

SERVICE MANUAL soa,. OISTAftfCE BETWEE .. TWO PAIRS OF LEADS SHALL NOT BE A._ LESS THAN MAXIMUM JNN[R WHEEL !SPAN OF AAJLROAO CARS USING Thf CROSSI-.G.

t.::l.• o.c .. INPUT SHALL BE SIZEO TO INSURE a.a TO u.2v DC ACROSS MM-21 T[RMI .. ALS 11 ' t, TAKI-.G INTO ACCOUP\IT o.u<D MSISTANCE OF SURGE RJPPU FILT£R&(tlHCfll REQ'o) ~o A ~l"IAL MM-21 CURRE'ff DRAIN OF ••• ,,,,..

&- SURGE RIPPLE FILTER IS REQUIRED WHEN DC 1 .. PUT SOURCE RIPPLE EXCEEDS O.SV PEAK TO PEAK. USE SURGE RIPPLE FILTER .. 4SIOJ6-0l01 FOR Af'O RECEIVERS Al'CO LOW POWER AFO TRANSMITTERS. USE SURGE RIPPLE FILTER "4510JI-Ol0! FOR HIGH POWER l,.FO TRANSMITTERS AW IIM-21 UNITS.

£= IT IS ~CESSARY TO PLACE R"IL TO R"IL SHU"JTS AT THE REQUIREJ APPROACH WARNl"JG odT,,.,,CE FROM THf. CROSSl'lilG. THESE SHUflfTS ARE TO BE PLACEO "'. flN THE LIMITS 0£Fl"IEO IN TH£ F'qEQUENCY SELECT ION CHARTS l"I HAVICE W'..._,AL 6089· THE WAR"111"4G zo....r SHOULD BE AARA,.,,GED AS SYMETRICALLY AS POSSIBLE

I

HOWEVER, ACCEPTABLE PERfORM.l'NCE CAN GENERALLY BE OBTAl"JED FOR CO-..FIGURAT IONS HAVI .. G UP TC I .3 : I U .. 8ALANCE. USE ~ SERIES RESONANT St1UNTS FOR t.-.-21 APPLICATIONS INVOLVING OTHER SIGNA.LS (AC OR oc) USl"JG THE RAILS - (1NC/.PSUL/.T(O FOR BURIAL BELOW FROST LEVEL)•

MM-21 FR[QU["J«:_Y.....i.t!tl ,o 7

>10 uo 405 570 6]0

TU'fEO SHUNT PART NO· '4451039-240 I t.1451039-2402 t.14510)1-240] N45103t-2404 N4510l9-2405 t.1451039-2406

~ BONDED (DOUBLE BOt.101 .. G IS RECOMMENOED} OR WELDED RAIL.

& USE #t AWG FOR GROUND WIRE. GRO\INO WUlES SHOULD BE KEPT AS SHORT AS POSSIBLE WITHOUT SHARP BE-.OS. GROUND CON"E'CTIONS SHOULD BE t.fAOf'. TO THE

&= ~~~L~:.~=~~ :~;Q~;!~~:s r:"'n: ~~~~~=L:R:~~s~~2 ~A:~;Q::,;::cs.

W-21 F'A£QU£!'fCY (HZ) COMPATIBLE AFQ t;l F'R£Qy£ffCY {HZ) 207------.. -----------115 tlO J 120 I 3 30 2720 2,0------------------10 sO, u io ' ' 310---·--·--------··-tlS ,tSO, 10 SO, 1130, 1420, 2140

12540

405------------------IIS ,no, 10 so, 1 120, IJJO, 1420, I ltO, 2140

570---------·--.. -----115 ,tso 1

10 50, I l 30, I 420, 1110 1

21 40, 2540

IJ0------------------115 .uo, 10 50, I I 20, I 3 30, I 420, Z 140 1

2120,u,o ,3410

Li'.1- RELAY TO IE SELECTED WITH REGAIIO TO SYSTEM VOLT AG[.

W'lAPAROl.tfO VIA AFO TRACK CIRCUITS

- APPLIES f'OA s IGNALEO/HON-S IGNALED TERR I TORY. - WITHOUT INSULATED JOINTS LOCATED IN WARNING ZONE. FOR APrLICATIONS

l,_.VOLVl"4G INSULATED .JOI .. TS WITHIN THE WAR .. ING ZONE REFER TO f'IG· 1-10, - WITHOUT SWITCH(s) LOCATED l'i WARNING ZON£. , - WITH WAAPAAOU .. D (AFO-AREA WAR~l'fG).

UNION SWITCH & SIGNAL m

I: WARNING ·-

[ AST80U"40 APPROACH LIMIT

..1-·r -----------WESTBOUND APPROACH :1

A

&

&:. N t ,~, J .

D

• : L!4 I I L 1

~fl!f ISLAND Rl!lAY

(OPTIONAL)

I

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External Wiring With Single AFO Wrap Around

6252, p. 2-11/2~12

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UNION SWITCH & SIGNAL EB

I: 'AH BOU"° APPROACH L IMll

i WARN I NQ z(}NE

+ ROAOIIAt-' -l"°"----------5TBOUNO APPROACH

I ~ ! I' LIMll

:1

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(OPTIONAL)

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6252, p. 2-13/2-14

UNION SWITCH & SIGNAL ffi

3 • 1 MOUNTING

SECTION III INSTALLATION AND ADJUSTMENTS

The Motion Monitor case is designed to be either shelf, wall or rack mounted. Mounting brackets may be turned 90° to accommodate shelf mounting. By reversing the mounting brackets, the Motion Monitor can be mounted in a rack with plug-in relays without exceeding the clearance line of above relays.

3.2 EXTERNAL EQUIPMENT

The following additional equipment is required for proper operation of the Motion Monitor (See Figure 2-1).

a. Motion Monitor Relay (Type PN-150BH, Part No. N322511-007)

This relay is deenergized when a train approaches the crossing within the detection range at a speed not lower than the minimum detectable speed. The relay is also deenergized when a train is within the island circuit which is defined as the length of track between the two sets of track connections. The positive control of the relay coil is connected to terminal 6 of the Motion Monitor, and the negative control to terminal 8 of the Motion Monitor. The relay is also an integral component of the timing circuit and requires the use of one set of FB contacts. The heel is returned to terminal 12, the back to terminal 14, while the front is returned to terminal 10.

b. Island Relay (Type PN-150BH, Part No. N322511-007) or.(Type PN-150B, Part No. N322500-901)

Some applications may require use of an external island circuit detector relay. When required, the positive control of the relay coil is connected to terminal 13 of the Motion Monitor and the negative control of the relay coil is connected to terminal 11 of the Motion Monitor.

c. Surge-Ripple Filter (12 Vdc, 2.5A, Part No. N451036-0702)

A Surge Ripple Filter is required when the power supplied has ripple greater than 0.5 volts peak-to-peak.

d. Track Coupling Unit Tuned Shunt

The Track Shunt is used for stabilization of track circuit characteristics, and in some cases where the motion detection zone is required to be less than that of the Motion Monitor's effective range.

6252, p. 3-1


For application see Section II. 2-1.

For typical connections see Figure

e. Lightning Arresters

Freq.

207 Hz 230 Hz 390 Hz 405 Hz 570 Hz 630 Hz

Part No.

N451039-2401 N451039-2402 N 451039-2403 N451039-2404 N 451039-2405 N451039-2406

Lightning arresters are used to protect the Motion Monitor by limiting the surge voltages entering by way of either the track or battery line.

Part No.

X451552-0101 X451552-0201 X451552-0301 X451552-0302

3.3 CONNECTIONS (See Figure 2-1)

a. Rail Connections

Description

Rated breakdown, 50-300V Rated breakdown, 500-1200V

-Same as N451552-0101, with terminal block Same as N451552-0201, with terminal block

The transmitter and receiver connections must be made with twisted pairs (three twists per foot). The two twisted pairs must be separated as much as possible. The loop lead resistance is to be held to 0.15 ohms or less for transmitter track leads (terminal 5 and terminal 7) and to 0.5 ohms or less for receiver track leads ( terminal 15 and terminal 17) •

b. Battery Connections

The power supplied must be minimum of 8.8 Vdc and a maximum of 16.2 Vdc at the Motion Monitor's terminals (terminal 11 positive.and terminal 9 negative).

Maximum ripple voltage should not exceed 0.5 volts peak-to-peak. A surge ripple filter must be used when the ripple is greater than 0.5 volts.

c. Lightning Arresters

Lightning protection for the Motion Monitor is to be provided as shown in Figure 2-1. Ground wires should be as short as possible and without sharp bends.

6252, p. 3-2

UNION SWITCH & SIGNAL ffi A lightning shunt arrestor should be connected across the de power source (USG shunt, low voltage X451552-0101.

For protection of the Motion Monitor from surges entering from the track, both series to ground (USG series, high voltage with terminal block X451552-0302) and shunt (USG shunt, low voltage X451552-0101) protection should be installed as shown in Figure 2-1.

d. Ground Connections

Ground wires should be kept as short as possible without sharp bends. Ground connections should be made to the common low voltage ground bus system that includes grounds at cases or houses. Make ground connections with f/6 wire. Messenger wire or metallic sheath of cable, if used, may serve as ground tie~in between cases or houses.

e. Relay Connections

Relays should be connected in accordance with Figure 3-1. If the relay has front testing, remove the wire from +A and connect it to the +T terminal of the relay. This applies to both the Motion Monitor relay and the Island relay.

3.4 TRACK STRAP

The Motion Monitor MM-25 features a track length sensitivity adjustment consisting of a strap 1 mounted across either terminals 1 and 3 (long track), or terminals 2 and 4 lshort track). The selection of the proper position of the strap is influenced by such operating conditions as the length of the approach zone, operating frequency of the MM-25 unit, and the minimum track ballast resistance encountered at the particular highway crossing. These conditions are accumulated in Figure 3-2, 3-3 and 3-4 on which benchmark "a" depicts the dividing line up to which distance a terminati,on shunt requires a shorting strap across terminals 2 and 4. A termination shunt placed across the track at a point in excess of the benchmark distance "a" (Figures 2-2, 2-3 and 2-4) requires a shorting strap across terminals 1 and 3.

3.5 ADJUSTMENT PROCEDURE (Reference Figure 2-1)

The Motion Monitor has three potentiometer adjustments.

a. "TIME" potentiometer, adjustable from 6-36 seconds and factory adjusted to 20 seconds.

b. "ISLAND" potentiometer.

c. "LEVEL ADJUST" potentiometer for high-level detector.

6252, p. 3-3


In most applications, the factory set 20 second delay time will be satisfactory and the only Motion Monitor adjustments will be the setting of the "ISLAND" and high level detector potentiometers, as described below.

a.

b.

*

Turn the "LEVEL ADJUST" potentiometer relay clockwise and press and release the TEST/RESET pushbuttons. This will disable the high-level detector to allow adjustment of the ISLAND and TIME potentiometer.

CONNECT a 0.06 ohm test* shunt across the track on the island receiver's side of the crossing at the location where it is desired to define the limit of the island zone. This usually will be at the point where the island receiver's leads connect to the track; but might be farther from the crossing if it is desired to extend the island zone beyond its physical limits. In no case should the test shunt be placed within the island zone; that is, between the points where the island receiver's connections and the transmitter's track feed connections (opposite sides of the highway) are made.

At high frequencies the inductive component of the standard shunt becomes rather large compared to 0.06 ohms. Instead use 5 foot pieces of Belden ://8670 ( 480 x 30 strands, • 75" wide) braided cable, bundled together with electrician's tape and connected to a rail clamp on either end according to the following frequency schedule:

MM Frequency (Hz)

Island Frequency (Hz) Part fl

fl of 5' Pieces

207,230 390,405 570,630

12280 15000 20000

N451554-0101, 0102 N451554-0103, 0104 N451554-0105, 0106

4 5 5

c. If the motion monitor relay is deenergized: turn the potentiometer clockwise all the way and wait approximately 20 seconds until Motion Monitor relay is energized.

Proceed to step d.

d. If the motion monitor relay is energized:

1. turn the potentiometer slowly counterclockwise just to the point where the relay deenergizes.

2. remove the test shunt.

3. check that the relay is now energized. If the relay fails to energize, Step d1. was improperly performed. Repeat steps a through d3. inclusive.

4. connect the 0.06 ohm test shunt across the track at the point where the track feed leads are connected to the rails.

6252, p. 3-4

UNION SWITCH & SIGNAL m 5. check that the relay is deenergized.

If the relay fails to deenergize, check all four track lead connections to see that they agree with Figure 2-1. Make necessary corrections and repeats step a through d5.

THIS CONCLUDES THE ISLAND ADJUSTMENT PROCEDURES

e. remove the test shunt from the track.

f. tighten lock nut of "ISLAND" potentiometer.

g. Attach a DC voltmeter (Simpson 260 or equivalent) across Motion Monitor terminals 16(+) and 9(-). Using Figure 3-1, find the proper high-level detector reference voltage, based on Motion Monitor frequency and approach length (in case of unequal approach lengths, use the shorter of the two). Add 300 ft. to this length if tuned shunts are used bypass insulated joints in both of the approaches. For example, a 405 Hz Motion Monitor using 2300 ft. approaches would require a reference voltage of 2. 80 Vdc. Adjust the "LEVEL ADJUST" potentiometer until the voltmeter reads this voltage and tighen the locknut.

h. To check high-level detector operation, press and hold down the TEST /RESET pushbutton. The TRACK FAULT LED will come on and both the island and motion relays will deenergize. After releasing the pushbutton, the TRACK FAULT LED will go off and stay off and both relays will be energized after the appropriate time delay. If the TRACK FAULT LED should come back on, check rail bond connections and recheck the high-level detector reference voltage level.

If a 20 second delay time is not applicable to the particular site situation, the ltTIME" potentiometer can be adjusted as follows:

a. Loosen nut of "TIME" potentiometer.

b. For less time, turn potentiometer counterclockwise, and for more time, clockwise.

c. To measure the delay time after adjusting potentiometer, proceed as follows:

1. Momentarily short terminal 15 to 17 on the Motion Monitor Unit. The M1 relay will deenergize.

2. With a watch, measure the elapsed time that the MM relay stays deenergized.

d. Repeat steps band c until the desired delay time is obtained.

e. Tighten lock nut.

6252, p. 3-5

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°' 6Vt--~~~~~~~-+~~~~-+-~~~--~~~~1--~~~-1-~~~~~~~~-+-~~~~~~~~+-~~~~

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207Hz 5V

w (!) <(

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-3V

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1000' 2000' 3000'

APPROACH LENGTH

4000'

Figure 3-1. Voltage Vs. Approach Length

5000'

EE c z 0 z I ~ :c • en c5 z > r

SECTION IV OPERATION

4.1 Basic Components (Reference - Figure 4-1)


The Motion Monitor MM-25 comprises a motion transmitter and receiver and an island transmitter. Both transmitters as well as the receiver share common rail connections, while the island reciever is connected separately.

4.2 Transmitters

The motion oscillator is coupled to the power amplifier with a large negative feedback to produce a constant current track source. One output lead is coupled to the rail by way of the track filter (a series resonant circuit) and the other output lead is coupled to the low frequency modulator which connexts to the opposite rail. The output of the modulated carrier circuit is coupled to a unity gain amplifier having low output impedance. The output of the amplifier is then coupled to the track by means of a high pass filter.

4.3 Motion Receiver and Differentiator

The motion receiver is a sharply tuned detector that monitors the voltage across the rail impedance and canpares this with a bucking voltage developed at the output of the transmitter's tuned filter. The output of the receiver is coupled to the differentiator which responds to any change in the inter-rail voltage caused by train movement.

If no train is present, or one is stopped within the motion monitor's approach, the output from the differentiator is sufficient to place the no motion - receding train oscillator in oscillation. Similarly, a receding train will cause a greater output from the differentiator and the no motion receding train oscillator will be placed into oscillation.

However, a fast approaching train will cause the differentiator's output to reverse polarity and stop the no motion - receding train oscillator.

4.4 Island Receiver

The island receiver detects the presence of railroad cars in the near proximity or on the island circuit. The island receiver also includes in its output a rectifier and filter. The island receiver's rectified output is coupled to the vital gate circuit.

625~, p. 4-1

"' I\) \J1 I\)

't:I . .i= I I\)

B v E

A D

X y A .,

·1 ------------- --------r--------------- -- ------------, I TRANSMITTER I RECEIVER I I 5 7 HIGH-LEVEL 15 17 RECTIFIER I I DETECTOR I FILTER AND I I RECEIVER ISLAND VITAL GATE I I HIGH PASS I AMPLIFIER RECEIVER RELAY I I FILTER _ __?RIVE'2.__ I I '1 TIMER I I I

POWER AMPLIFIER

•

SERIES RESONANT

TRACK FILTER

•

LOW FREQ. MUL TIVIBRATOR

AND. MODULATOR

r.

I I I I I DIFFERENTIA_TOR I I -------- I I NO MOTION AND I

RECEDING TRAIN TO ALL I I OSCILLATOR P.C. BOARDS I I -------- ~ I Ir__ v1TAL GATE --- 12 a - 6 -- 9 11--!.--13 I

- + i..., r.J I - + BATTERY i..1..1 ... ."'f-l MOTION MONITOR ISLANDRfLAY I RELAY (OPTIONAL)

I ISLAND POWER MOTION I I CARRIER AMPLIFIER _ OSCILLATOR I

AND MOD. "" AND I I OSCILL. PRE·AMP I I I I I L-------------------------~

KEY TO SYMBOLS

fi -TWISTED PAIR 3 TURNS/FT.

Figure 4-1. Motion Monitor Block Diagram

EB c z 0 z i ~· :c IIP en Q i .....

UNION SWITCH & SIGNAL m 4.5 Vital Gate Logic and Relay Driver.

Outputs from both the island receiver's rectifier and filter and from the no motion-receding train oscillator are applied to a vital gate circuit which includes modulation check circuitry. The island receiver gating voltage can be interrupted by the High-Level Detector if it senses an increase in impedance within the approach zones. The output of the vital gate is applied to the Motion Monitor relay driver. The relay driver is a power amplifier that boosts the input to a sufficient level to drive the Motion Monitor relay.

If no train is present, or one is stopped in the approach track circuit, and if the high level detector has not been tripped, both outputs are present to the vital gate circuits (one from the no-motion receding train oscillator and one from the island receiver).

If the high-level detector is tripped, it will interrupt the island receiver gating voltage. Since only one of the gating voltages will be present, there will be no input to the relay driver, and the Motion Monitor relay will be de-energized.

Consequently, with both inputs present, the vital gate circuits will be "gated-on" and signal voltage will be supplied to the relay driver, causing the Motion Monitor relay voltage to be present.

When a train is approaching at a given speed and distance from the crossing so as to cause the inter-rail voltage to fall at a sufficient rate and produce a negative output from the differentiator, there will be no output from the no-motion receding train oscillator. The island receiver will apply an output voltage to the gates; however, since both outputs are not present at the vital gate circuits, the gates will be "gated-off", removing power to the relay driver. With no input voltage to the relay driver, the Motion Monitor relay will deenergize, causing the highway crossing warning devices to be activated.

When the Motion Monitor relay is deenergized, the timing circuit is enabled through the back contact of the relay. The Motion Monitor relay will not be energized again until the elapsed time equals the time set by the potentiometer of the internal timing circuit, and then only if the train has stopped approaching the crossing or is receding from it.

When a train has occupied the island circuit, there will be no output from either the no motion - receding train oscillator or the island receiver. With no input voltages to the vital gate circuits, there will be no input to the relay driver. The relay driver having no input causes the Motion Monitor relay to remain de-energized.

When a train has proceeded through the crossing to the point where the last car's rear wheels have cleared the island circuit, both the no motion -receding train oscillator and the island receiver outputs will be present at the input to the vital gate circuits causing the gate to turn on. An output gate voltage will be supplied to the relay driver causing the Motion Monitor relay voltage to be present, and if the internal timer has run its time, the relay will be energized and thereby deactivate the highway crossing warning devices.

6252, P.· 4-3/4-4

SECTION V FUNCTIONAL DESCRIPTION

5.1 SIGNAL BOARD (See Figures 5-1 and 5-2)


Since any modulation of the transmitter due to power supply changes would have a negative effect on the receiver, the circuitry has been designed to be immune, as nearly as possible, from power supply changes. For example, the oscillator, Ql, is designed to have Zener diode regulation of its power supply, with the diode's impedance in series with the oscillator tuned circuit, so if the diode were to open, the Q of the tuned circuit would be reduced so that the oscillator will not oscillate. This assures that the transmitter will not operate with the oscillator in an unregulated condition. Resistor R2 and R3 provide further compensation by feeding a portion of the power supply change to the oscillator base bias circuitry in such a manner that the oscillator output actually falls slightly for a supply voltage increase. This compensates for tendencies in the opposite direction due to Zener diode impedance and imperfections in the subsequent stage's gain stability. The output of the oscillator is coupled by transformer Tl to the pre-amplifier made up of transistors Q2, Q3, Q4 and Q5. Since this amplifier's most sensitive point is to power supply ripple in its input bias network, it is filtered with a four terminal capacitor, C4. The pre-amplifier is capacitively and transformer coupled by C7 and T2 to the power amplifier made up of Q6, Q7, Q8 and Q9. Since it was found that this power amplifier could be modulated by changes in its input bias, its base bias voltage is also supplied from the oscillator Zener voltage. The power amplifier uses emitter degeneration to make it independent of power supply changes and also to make it act as a constant current source. The power amplifier is transformer coupled, by T3, to the rails through a series resonant filter, T4 and cg. Part of the voltage across the inductor of this tuned circuit is used for bucking purpose, since it will be constant regardless of train position. Transformer T3 provides the phase correcting part of the bucking voltage.

The modulator circuit consisting of QlO, Q11 and Q12 functions as a conventional multivibrator, oscillating at approximately five (5) cycles per second, the desired modulation frequency. Q11 drives Q10, which acts as a switch to alternately short and unshort the high voltage secondary of the modulation transformer T6. Current flowing from the series resonant filter through the primary of the modulation transformer, on its way to the rails, induces a small voltage in the other secondary which is in series with rail input to the motion detector receiver. Conduction of Q10 removes this small voltage. Diode D9 protects this circuit from surges.

625?, p. 5-1


5

,.... MODULATOR

POWER SERIES i-- MOTION

OSCILLATOR _.. PRE-AMP f-t AMPLIFIER ~ RESONANT - RECEIVER

FILTER AMPLIFIER

Figure 5-1. Signal Board Block Diagram

7

i--

~ TODE (VOLTA

TECTOR PCB GE DOUBLER)

The algebraic sum of the track voltage, the bucking voltage, and the modulating voltage is fed to a tuned transformer, T7, which serves as the input of the motion receiver. Surge protecting diodes, D10 and D 11, are connected to the secondary of this transformer. The transformer drives the motion receiver amplifier made up of Q13, Q14, Q15 and Q16. This amplifier drives a transformer, TB, which steps up the voltage to be fed to the voltage doubler on the Detector PCB.

5.2 DETECTOR BOARD (See Figures 5-2 and 5-3)

The output of the island receiver on the Island Board is rectified and filtered by D5, D6, and C9. This signal is then gated by the high-level detector, consisting of IC1 and IC2 and their associated canponents. IC1 Amp 1 is connected as an 8.0 volt regulated power supply using Zener D25 and R57 and R58 to provide a temperature compensated voltage reference. IC2 Amp 1 is a comparator which supplies base current to Q2 and Q1 only during "turn-on" conditions. Q15 and Q16 provide current gain so that the power supply can act as a stable reference for the remaining amps of IC1 and for the adjustable comparator reference voltage set by the 50K ohm potentiometer.

IC1 Amp 2 is an active bandpass filter which filters the motion monitor track voltage before it is rectified by IC1 Amp 3. This voltage is then filtered by C38 to provide a low ripple de voltage that is proportional to the ac Motion Monitor voltage. Comparator IC1 Amp 4 compares the Motion Monitor voltage

6252, p. 5-2


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igure 5-2. MM-25 Circuit Diagram

-0

m

6252, p. 5-3/5-4 -·-


5 7

FROM SIGNAL PCB VOLTAGE --+ DIFFEREN- --+ NO MOTION HIGH-LEVEL RECTIFIER +- ..... - -(MOTION DOUBLER TIATOR OSCILLATOR DETECTOR FILTER ~

FROM RECEIVER)

l ISLAND

l • VOLTAGE

___. MODULATIONi--GATE ... DOUBLER MOD. DET r AMPLIFIER

- -""' ..

RECTIFIER/ ...

AND/OR RELAY ... --- ~ - TIMER ..... :-+ MOTION FILTER GATE AMPLIFIER ...

j ~ RELAY

• I I

Figure 5-3. Detector Board Block Diagram

signal with a reference voltage set by the 50K ohm potentiometer. If the Motion Monitor voltage exceeds the reference voltage, comparator IC1 Amp 4 output goes low, turning off Q17 and Q18 to interrupt the island receiver gating voltage to turn off the Motion Monitor relay driver. The low output of IC2 Amp 3, whose output starts increasing linearly from O volts. After approximately 10 seconds, its output will be high enough to turn on the latching comparator IC2 Amp 2, which lights the Track Fault Indicator LED 1 through Q19.

Pressing switch S1 simulates a high track level by putting a high de voltage on the negative input of comparator IC1 Amp 4. Pressing the switch also disconnects C10 from the feedback loop of IC2 Amp 3, allowing LED1 to light immediately. Releasing S1 causes a pulse which triggers the one-shot IC2 Amp 4. The output of IC2 Amp 4 stays high for several seconds, forcing the latch IC2 Amp 2 and LED 1 to remain off while the circuit stabilizes.

The output of the motion receiver in the Signal PCB is fed to the voltage doubler to drive the differentiating capacitor.

PCB

625.2, P• 5-5


WARNING

THE VOLTAGE DOUBLER CIRCUIT DEVELOPS UP TO 300 VOLTS DC. AVOID CONTACT WITH TERMINALS WHEN THE UNIT IS ENERGIZED TO MINIMIZE THE POSSIBILITY OF PERSONNEL INJURY.

A Two section RC ripple filter using two 4 terminal capacitiors, C2 AND C3 is employed to reduce the possibility of passing unwanted carrier frequency ripple through the differentiating capacitor C4 on the 5 cycle per second modulating frequency signal.

While the five cycles per second modulating frequency must be passed through the differentiating capacitor, any carrier frequency ripple getting this far could result in an unsafe condition, so ripple filtering is provided by a two section RC filter using two, four terminal capacitors, C2 and C3.

The differentiating capacitor, C4, must be of a very high quality, since it will have to withstand several hundred volts across it and still exhibit a low leakage compared to the 1-1/2 microamp signal which results from the slowest moving train which can be detected. The output of the capacitor is coupled directly to the no motion or receding train oscillator, Q1. This oscillator operates at approximately 1-1/2 microamps of power supply current, and an approaching train serves to buck or overcome this current, thereby turning the oscillator off. This supply current must be of a known value and vital in nature, therefore power for this oscillator is derived from the Zener diode in the transmitter oscillator on the Signal PCB. If no trains are moving toward the crossing, this oscillator will be oscillating and modulated at 50% or more by the five cycles per second recovered modulation being passed through the differentiator. The output of the no motion oscillator is transform.er coupled by T1 to the gating transistor, Q3. This transistor has its power supplied by the island receiver through the rectifier/filter and the high - level detector. If the island is occupied or if there is a high a track level, this de output goes away and Q3 provides such a heavy loading on the oscillator, that it stops completely. The output of the gate goes to three places, (1) the voltage doubler/modulation detector, (2) the modulation amplifier, and (3) the AND/OR gate. The output of the gate is first capacitive coupled to a voltage doubler which once again demodulateds the five cycles from the oscillator output, filters out the oscillator frequency, and couples the modulation to the modulation amplifier. This amplifier is made up of transistors Q4, Q5, Q6 and Q7. The output of the amplifier is rectified and filtered by 012, 013 and C19, then fed to the AND/OR gate, Q8. This gating voltage is a check of the oscillator, Q1. Thus, Q8 will have an output if there is de provided for its collector from the rectifier filter (this de resulting from either the recovered modulation, or from a large oscillator output due to a rapidly receding train) and if a high frequency is coupled to the base of Q8 from either the no motion oscillator by way of the gate, or from the limit detector on the Signal board. Thus, transistor Q8 can be considered to be an OR gate at its base input, and an AND gate with respect to the combination of its base and collector inputs. The output of the AND/OR gate is coupled to a four transistor relay amplifier made up of Q9, Q10, Q11 and Q12.

6252, p. 5-6

UNION SWITCH & SIGNAL ffi This amplifier is used to provide enough power to drive the motion relay. An output transformer, T2, is used to insure that sufficient relay voltage is available at the lowest power supply voltage to be used.

As the motion monitor relay is deenergized, both the Colpitts oscillator circuit, Q14, and the programmable unijunction oscillator circuit, Q13, are connected to the negative battery by the back contact of the motion monitor relay. The programmable unijunction transistor oscillator will time out according to the charging rate of capacitor C24, as determined by the value of R35 and the setting of R2-A and will be allowed to trigger the gate if, and only if, the detection circuit indicates that the motion voltage has come back up enough to hold up the motion relay. The inhibit of the trigger is accomplished by clamping the gate of the PUC to B+ by way of the back contact of relay RY1. As C24 is being charged, capacitor C29 is being charged through resistor R44 and R2-B and will have sufficient charge at 3/4 through the delay time setting to pick up the motion monitor relay when the gate is triggered. The operating margin compensates for small supply voltage fluctuations, tolerances in C29, and the relay coil pick-up power due to temperature changes. After pick-up, the timing circuits are inoperative and the motion relay is held up by the motion voltage at the output of T2, through its own front contact and diode 021.

5.3 ISLAND BOARD (Refer to Figure 5-2 and 5-4)

To overcome large ring-by distances associated with low frequency island circuits, a high frequency carrier circuit is utilized by the MM-25 Motion Monitor. The output of carrier oscillator, Q9, is chopper modulated by Q10 at a value as is determined by oscillator circuit, Q8. Capacitor C19 and inductor L3 filter the resulting modulated signal and remove the low frequency component and high frequency harmonics. Potentiometer R1 mounted on the front panel provides sensitivity adjustment. Integrated circuit IC-2 along with transistors, Q12 and Q13, make up a unity gain amplifier having low output impedance. Transformer T4 and capacitors C21 and C22 comprise a high pass filter to couple the output to the track. Diode 07 along with diodes 011, 012 and 013 provide surge protection. The receiver portion of the Island Board is shown on the left side of the circuit diagram in Figure 5-1. Capacitors C1 C2, C3, transformer T1, and inductor L1, comprise a high-Q bandpass filter. The output of the filter is demodulated by detector diode 01, and applied to emitter followers Q1 and Q2. Integrated circuit IC-1 is a temperature compensated circuit which amplifies the signal to a working level. Capacitors C9 and C10 and diodes D3 and D4 produce a negative de voltage from the amplified signal to operate an oscillator which acts as a level deflector. The 22 KHz output signal of the oscillator is amplified by transistors Q4, Q5, Q6 and Q7 which is then applied to the detector board where it is rectified and filtered to enable gating transistor, Q3.

6254, p. 5-7


15 17

TUNED XFMR

HIGH Q BANDPASS

FILTER

DEMODULATOR

AMPLIFIER &

NEGATIVE DC MAKER

TO DETECTOR

BOARD

7

HIGH PASS

FILTER

5

AMPLIFIER &

GAIN CONTROL

CHOPPER MODULATOR

CARRIER SCILLATO

ODULATIO SCILLATO

Figure 5-4. Island Board Block Diagram

6252, p. 5-8

SECTION VI FIELD MAINTENANCE


With the exception of replacing a fuse or repairing an obvious fault, such as a broken wire, it is recommended that a defective Motion Monitor Unit be replaced with a good unit.

6. 1 FUSE REPLACEMENT

The fuse that protects the Motion Monitor's circuitry is located on the cover. Cause of overload should be determined and fixed before a new fuse is inserted. Replace the defective fuse only with one of the same value; 3 Amp. @ 125V, 3 AG, SLO-BLO (US&S Part No. J085075-1020).

6.2 FIELD EQUIPMENT AND TESTS

The following list of voltage measurements will enable maintenance personnel to distinguish between external wiring and internal circuit problems.

The following measurements are made with a track shunt applied at the point on the track that produces a 0.45 volt RMS signal across the transmitter leads, terminals 5 and 7, with a battery voltage of 12 Vdc across terminals 11 (+) and 9 (-).

AAR TERMINAL

5 and 15 and

11 (+) and 6 C+) and

13 C+) and 16

7 17 9 (-) 8 (-)

11 (-)

VOLTAGE REQUIREMENT

0.45V RMS 0.45V RMS 12V de 6 to 7V de with 5 Hz Mod. 6 to 8V de For high level detector reference voltage (see section 3.5, step g)

Monitoring of the 3 LEDs on the cover of the Motion Monitor and a check on the state of the island and and motion relays will indicate the condition of the unit. With no track shunt applied and no high level detected, the two relays are to be in the energized state, the "ISLAND" LED indication on steady, the "MOD CHECK" LED indicator flashing on and off at a 5Hz rate, and the "TRACK FAULT" LED off. If the relays are de-energized and the "TRACK FAULT" LED is on, then there is a problem with the track or connections to it, and all bond connections and MM-25 track connections should be checked. If the relays are energized, the "ISLAND" LED on, the "MOD CHECK" LED flashing, and the "TRACK FAULT" LED on, then there has been an intermittent track problem and again all bond connections and MM-25 track connections should be checked.

6252., p. 6-1


To test the high-level detector and the "TRACK FAULT" LED, press and hold down the TEST /RESET PUSHBU'ITON, THE "TRACK FAULT" LED will come on and the relays will be de-energized. To turn the "TRACK FAULT" LED off once track problems have been corrected, press and release the TEST/RESET pushbutton.

6.3 PERIODIC MAINTENANCE

Regular inspection and corrective action should be taken to keep the effective series loop rail resistance in each direction from the feed point of the Motion Monitor track circuit as low as possible. Good maintenance practices are encouraged so as to maintain high ballast resistance, insure integrity of the rail bonds, MM-25 rail connections and rail splices to maintain a low electrical resistance. Field tests and checks described in Section 6.2 should be made routinely at least every 6 months to ensure proper operation. Field tests and checks as described in Section 6.2 should be made routinely at least every six months to ensure proper operation.

6252, p. 6-2

SECTION VII SHOP MAINTENANCE


The Motion Monitor MM-25 has been designed in accordance with vital design principals. As with vital relays, the repair of motion monitors should be done by qualified personnel. For prompt repair service, please contact your nearest Union Switch & Signal sales representative for information on returning the defective unit.

6252, p. 7-1/7-2

June, l9.83 WP0168A A-6/83-250-2496-l

PRINTED IN USA

SERVICE MANUAL 6252 APPENDIX A

Parts List

MOTION MONITOR MM-25

Part Numbers ·

N451554·0107 N451554·0108 N451554·0109

N451554·0110 . N451554-0111

· N451554·0112

UNION SWITCH & SIGNAL DIVISION AMERICAN STANDARD INC./ SWISSVALE, PA 15218

ITEM

1 2 3 4 5 6 7 8 9

10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39

UNION SWITCH & SIGNAL m, MOTION MONITOR MM-25 ASSEMBLY PARTS LIST

(See Figure A-1)

DESCRIPTION US&S PART NO.

ORDERING REFERENCE (Complete Unit)

Motion Monitor, MM-25, 207 Hz N451554-0107 Motion Monitor, MM-25, 230 Hz N451554-0108 Motion Monitor, MM-25, 390 Hz N451554-0109 Motion Monitor, MM-25, 405 Hz N451554-0110 Motion Monitor, MM-25, 570 Hz N451554-0111 Motion Monitor, MM-25, 630 Hz N451554-0112

Signal P.C.B., 207 Hz N451522-3502 Signal P .C. B., 230 Hz N451522-3503 Signal P.C.B., 390 Hz N451522-3504 Signal P .C .B., 405 Hz N451522-3505 Signal P .C .B., 570 Hz N451522-3506 Signal P.C.B., 630 Hz N451522-3507 Detector P .c .B., 207 Hz N451605-1402 Detector P .c. B., 230 Hz N451605-1403 Detector P.C.B., 390 Hz N451605-1404 Detector P .C. B., 405 Hz N451605-1405 Detector P .c .B., 570 Hz N451605-1406 Detector P .C. B., 630 Hz N451605-1407 Box R451~~~-oio1 Cover M451 -1 0 P .C. Mtg. Bkt., Right R451555-0201 P.C. Mtg. Bkt ., Left R451555-0202 Mtg. Flange M451555-5501 Terminal Block J077826 Terminal Washer J047818 Terminal Stud M380743 Nut M029103 Nut M029101 Diode, Light Em. MLED .650 J726150-0112 Potentiometer, 100K Ohms, 2W J062554 Potentiometer, Dual, 500K/20K J620850-0048 Fuse Holder J071889 Fuse, 3A Slo-Blo J710029 Liner J475168 Seal, Lead J079351 Wire No. 23 A043013· Terminal Jumper M120343 Screw, #8-32 x 1! J525111 Standoff J792737 Spacer J772378 Screw, #6-32 x 5/16 J507193 Lockwasher, /16 J047713 Nut, f/6-32 J048148 Screw, #8-32 x 5/16 J509815 Lockwasher, /18 J047714

6252, p. A-1


MOTION MONITOR MM-25 ASSEMBLY (Cont'd.)

ITEM DESCRIPTION US&S PART NO.

40 Screw, f/10-32 x 5/ 16 J507268 41 Screw, #10-32 x! Fillister Head M153231 42 Lockwas her, fl 10 J047715 43 Screw, &-20 x 1-1/8 J052508 44 Nut, &- 20 Lock J048203 45 Tubing, Shrink A774199 46 Wire , ff 22 Bare A043183 47 P.C.B., Island Ckt., 12.28 Hz N451522-3003

(For 207 and 320 Hz) 48 P.C.B., Island Ckt., 15.0 Hz N451522-3004

(For 390 and 405 Hz) 49 P.C.B., Island Ckt., 20.0 Hz N451522-3005

(For 507 and 630 Hz) 50 Bracket, Angle R451555-0203 51 Sleeve M172423 52 Cap-Molded J078147 53 Pot. 50K, 2W J062521 54 Switch J725707-0192 55 Cable Assembly N451458-3501

(External Parts)

Relay, Motion Monitor, Type PN-150BH N322511-007 Relay Island, Type PN-150BH N322511-007 Relay Mounting Base N349904 Surge-Ripple Filter, 12VDC, 2.5A N451036-0702 Track Coupling Unit Tuned Shunt:

207 Hz Unit N451039-2401 230 Hz Unit N451039-2402 390 Hz Unit N451039-2403 405 Hz Unit N451039-2404 570 Hz Unit N451039-2405 630 Hz Unit N451039-2406

-

6252, p. A-2

t + 2

9

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128

+++++++ +++++++

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I I


1 ··Lgure A-1. MM-25 Parts Assembly 1,:;•igLlL '-

I

6252, p. A-3/A-4

SERVICE MANUAL 6253

NO MOTION DETECTOR

JULY, 1982 -·-· ---A-7 /82-100-2504-1 UNION SWITCH & SIGNAL DIVISION

AMERICAN STANDARD INC./ SWISSVALE, PA 15218

PRINTED IN USA

Section

I

11

111

IV

GENERAL INFORMATION 1.1 INTRODUCTION 1.2 PHYSICAL DESCRIPTION 1. 3 INPUTS

INSTALLATION 2.1 MOUNTING

CONTENTS

2.2 ELECTRICAL CONNECTIONS

CIRCUIT DESCRIPTION 3.1 DETAILED CIRCUIT DESCRIPTION

MAINTENANCE 4.1 WHEN A FAULTY DETECTOR IS SUSPECTED

APPENDIX A - PARTS LIST

Table I Terminal Designation

Figure 1 Schematic Diagram

i


1 1 1 1

2 2 2

3 3

4 4

2

5/6

I-'· I-'·

CHASSIS

Ii CABLE GRIP CONNECTOR

PRINTED CIRCUIT BOARD

TERMINAL BLOCK

Figure 1. No Motion Detector

.. l .. TYPE ,:.-_ i=-,, -- RELAY

- 1

EB c z 0 z I ~ ::i: RP Cl> ci z )> r

1.1 INTRODUCTION

SECTION I GENERAL INFORMATION


The No Motion Detector is a car-carried solid state vital unit. It is designed to detect zero train velocity and will energize an internal relay when the brakes are applied and train speed is less than three mph.

1.2 PHYSICAL DESCRIPTION

Length: Width: Height: Operating Temperature

11-1 /2 inches 8-1/4 inches 5-1/2 inches -4o0 c to +10°c

The essential canponents are a relay, printed circuit board and a terminal block (see figure 1). These are mounted on a 1/4-inch thick micarta sheet and housed in a steel box. The mounting arrangement insures at least 1500 volts breakdown between the terminal block and the box. A tag is affixed to the lid of the box which identifies proper wtring connections to the unit.

The printed circuit board is plug connected and mounted to the chassis with six screws. Two LED's are mounted on the board. One LED will flash when brakes are applied and the car is at zero velocity. The other LED is lit continuously when the printed circuit board output is energized. All external connections (magnetic pickup, battery power, master controller and relay contacts) are made on the terminal block. The relay contact has a maximum power rating of 1 ampere at 30 volts or 0.333 ampere at 60 volts.

1.3 INPUTS

The No Motion Monitor will operate over a 24 to 45 range on both of its inputs. One input is connected to the master controller. When the controller is advanced for propulsion, power will automatically be removed from this input. The other input is connected directly to the car's battery. An isolated magnetic pickup equivalent to Electro Products Corporation type 3040A must be connected to the speed sensor inputs. Any other magnetic pickup may cause faulty operation of the unit.

6253, p. 1


2.1 MOUNTING

SECTION II INSTALLATION

The detector is bolted to the car floor through the four mounting holes on the unit's bottan plate.

2.2 ELECTRICAL CONNECTIONS

Electrical cables are run through the cable grip connector and connected to the appropriate terminal on the terminal block. Terminal designations are given in Table I.

Table I

Terminal Connection

1 Relay Contact Front

2 Relay Contact Heel

3 f15 Wire

4 Spare

5 Spare

6 - Battery

7 + Battery

8 Mag. Pickup

9 Mag. Pickup

The speed sensor or leads must be in shielded cable and the shield must be connected to the car frame ground. The battery inputs should be connected to a five amp breaker.

6253, p. 2

SECTION III CIRCUIT DESCRIPTION

3.1 DETAILED CIRCUIT DESCRIPTION (See Figure 2)

UNION SWITCH a SIGNAL m

When the car is at zero velocity, the gear tooth magnetic pickup is ti.med to C6 and connects to differential amplifier Q2, Q3. Current gain is provided by Q4, which drives gate Q5. When the gate is "on", by virtue of having its collector more negative than B+, positive feedback is provided through R10. R10 will provide enough feedback for oscillation if the pickup is in good condition. This 5 KHz oscillation causes Q6 to conduct at a rate determined by R1g, charging cg. When it reaches approximately the voltage determined by R22 and R24 as a divider, Q7 turns on and Q8 turns off. The collector of Q8 goes toward B+, which disables gate Q5, stopping the 5 KHz oscillation. This stops current in Q6, allowing cg to discharge until it reaches the level determined by R23 and R22. The Schmitt trigger (Q7, Q8) reverses, starting the cycle over again. This cycle repeats at a rate greater than 15 KHz. However, if the car is moving, a speed signal is generated, which also reaches the base of Q6. At some frequency (designated by selecting a value of C8), Q6 and Q7 will be held on. Q8 and Q5 will be off, the 5 KHz oscillation ceases, and the Schmitt trigger output no longer pulsates. Hence, presence of the 15 Hz pulsation at the collector of Q8 is an indication that there is no motion. This signal is rectified by D4 and D5 and used to power gate Qg. Note that points which have been shown by test to be susceptible to ripple have been filtered by C7. Feedback resistor R21 provides hystersis in detection of V = O.

The AC input to Qg comes from oscillator Q1 which receives its power from the brake control or the propulsion conmand line when brakes are applied. This source is filtered by R1, D1 and C1. An oscillator is used to sense the propulsion conmand so that common mode noise rejection can be achieved by transformer action. Transformer T1 is a pot core with a three section bobbin, therefore the secondary can be isolated by spacing it away from the primary Qg. Separation of secondary and primary windings of T1 combined with the high value of R1 severely reduces the possibility of circircuit B+ from feeding back into the 115 Train Line. The output signal of the oscillator circuit is a low voltage signal and is amplified by gate Qg, if Qg is energized by the V = 0 circuit. Thus, there will be an output from Q9 only if there is no motion and no propulsion conmand.

The signal from Qg is applied to relay driver Q10, 11, 12 and 13 which drives the relay via transformer T2 and rectifier D10. T2 uses the same isolation and shielding techniques as T1. The output is designed so that when Q12 and Q13 are conducting output diode, D10 is not. When Q12 and Q13 are not conducting magnetic energy stored in the pot core charges C 14 via D10 which is now conducting. This output arrangement allows Q12 and Q13 to operate with less. current. Capacitor Cl6 prevents high frequency oscillations which causes overheating of Q12 and Q13. If the relay load is disconnected, V2, R40 and LED 1 limit the output voltage rise which also would cause overheating of Q12 and Q13. Filter L1 and C5 as well as V1 protect against possible transients on the +B input. Four terminal resistor R27 limits the negative going swing of the base of Q6 in the event of a short in C8.

6253, p. 3


SECTION IV MAINTENANCE

4.1 When a faulty detector i.s suspected - Perform the following troubleshooting steps: (See Figure 1)

a. Remove the cover. LED 1 should be flashing and LED 2 should be continuously lit when the car is at zero veloci.ty, and brakes are applied.

b. If LED 1 is not flashing when the car is stopped and, power is applied to the unit (terminal 6 and 7), check the magnetic speed sensor and its associated wiring. Make certain that it is the proper sensor ( 3040A Electro Corporation or equivalent). If the sensor and its wires are correct, remove the printed circuit board and replace it with a board known to be functioning properly.

c. If LED 1 is flashing and LED 2 is not continuously lit with power present at terminals 3 and 6, replace the board with one known to be functioning properly.

d. If both LED 1 and LED 2 are not illuminated with power applied to the unit, replace the board with known to be functioning properly.

Any board found to be defective should be returned to Union Switch & Signal for repair.

6253, p. 4

TERMINAL BLOCK

CONNECTION I 1 <5 WIRE RI

TB3-------~"1,~_,T,_ _ __,T,----------------, I ~=9• I I I I I I I I I I

B-t WHEN IN BRAKE

01 IN968B

Cl l>l'O sov

ra6- -- - sAn<- •li•-r1". >-------4----4>---+_..--._--1 I I I I I I I I I I

I I I I I

TB8-----i--.Js-?'::> f I I f I I I

,02 IN750

J }b! 27Mf0 sov

03 I 1,M,i IN750

I I I I I I

: I

: r1iMAGNETIC I L,JPICKUP

I I I I I I I I I I I I

,R9 47K

IT

: i I I I 1 I I 1 :v. 19- - - - _I_ -e> ~m 'N'--,

I I I I I I I I I

16 IK

RI 1 IK

COL. QI

.. ~ 20P SEC/DIV

20VIOIV

R.2.1

360K

30V P-P

LEDi

68QG R22

COL 03

~~

~

20M SEC/OIV lOVIOJV

06 IN914

IGV P-P

COL I 08

.. ~ 18V P-P

20M SEC/DIV lOV/OIV

jAVE CB E C IN T V=O i


COL. 013

.. ~~M

I.EASUREO WITH THE D WITH A 30VOLT BOTH OC [NPUTS.

SPEED SIGNAL

20P SEC/DIV 20VIOIV

DRAWING D451349:sH. 1901 REV. 1

?~914 ~k~~ i

~~sts

R37 100" IW

--1 I

1-'-JRELAY t.. I ....J OUTPUT

I __ I

TERMINAL BLOCK

.~~E~TtfN

r-L-----TB2

EB

~----BATT<-> l<R':>-----l--1------------<L----------------------...!.-------!-------..__-l.---4>----+--_.-.._ _ _. __ .___ ___ .____~ RESISTORS I /4 WATT UNLESS OTHERWISE SHOIN

Figuire 2. No Motion Detector Schematic Diagram

6253, p. 5/6

JULY, 1982 A-7 /82-100-2504-1

PRINTED IN USA

SERVICE MANUAL 6 2 53 Appendix A

Parts List

NO MOTION DETECTOR

Part Number

N451447-1701

UNION SWITCH & SIGNAL DIVISION AMERICAN STANDARD INC./ SWISSVALE. PA 15218


ITEM

5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95

100 105 110 115 120 125 130 135 140 145 150 155 160 165 170

6253, p. A-2

DESCRIPTION

NO MOTION DIITECTOR PARTS LIST (See Figure A-1)

Box, Detector Chassis Screw, 10-32 x 1/2 Pn. Head Washer, 10 LK Washer, 10 Pl. Stl. PCB, No Motion Detector Screw, 6-32 x 1/2 Pn. Head Washer, 6 LK Washer, 6 Pl. Stl. Spacer Screw, 6-32 x 3/8 Pn. Head Connector, PCB Edge Bracket, Connector Mtg. Screw, 6-32 x 5/8 Pn. Head Nut, 6-32 Hex Stl. Strip, Terminal Screw, 6-32 x 3/4 Pn. Head Screw, 6-32 x 5/8 Pn. Head Bracket, Relay Mtg. Relay, "L" type Screw, 10-30 x 3/8 Fil. Head Screw, 10-32 x 5/8 Pn. Head Nut, 10-32 Hex Stl. Tag, Wiring Grip, Cable Nameplate Rivet, Closed End Strip, Marking Terminals Wire Tubing Tubing Ty-rap Lock Nut, 3/4 Conduit

PART NUMBER

M451448-9601 M451448-940 1 J507267 J047733 J475077 N451204-2501 J507022 J047662 J047996 J725898 J507262 J70c:J72 M451448-9501 J507023 J048148 J7240 3) J507008 J507023 M451448-9502 N384097 M451358-0106 J050971 J048172 M451559-9301 J7-12101 M451108-520 2 J490037-0015 J725897 J7 30049 A045779 A774 201 A774199 J7033)2 J048415

~--------- --------,~ :: ( 1 11 II I I I 11 ,--- -1 I I 11

1 I I I 11

11 I I I 1 11

II I I I 11

11 I I I 11

:, I I I I :1 I zl..---J I I 11

11 z I I I ii 11

I I 1 11

11 I I 1 11 11 I I II 11 I I I I II I I L_--r ___ _J I ii ii T I Ii ,±.._ 11 l ~IX) ) ,,-v

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Figm

motion monitor mm-25 - hitachi rail · oscillator and changes in signal strength due to train...

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