Trane Variable Frequency Drives Troubleshooting

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Touching the electrical parts may be fatal —

even after the equipment has been

disconnected from the AC line. To be sure

that the capacitors have fully discharged,

wait 14 minutes after power has been

removed before touching any internal

component!

DANGER!

BASIC INFORMATION AND REQUIRED EQUIPMENT

• REQUIRED REFERENCE MATERIAL

• REQUIRED TOOLS

• POSSIBLE USEFUL EQUIPMENT

• WHAT IS TROUBLESHOOTING

• DIVIDE AND CONQUER

• PHYSICAL INSPECTION

Required Reference Material YOU MUST HAVE THIS!

• INSTALLATION, OPERATION AND

MAINTENANCE MANUAL (GENERAL

INFORMATION)

• CUSTOMER CONNECTION DIAGRAM

(SPECIFIC FOR THE ORDER)

• SCHEMATIC DIAGRAM (SPECIFIC

FOR THE ORDER)

Hand tools Tool’s required

Screwdrivers, Standard & Phillips

Torx drivers T10-T50

Metric socket set, 7-17 mm

Lon extension (20”)

Torque wrench, 4-170 in./lb

Magnet

Nut starter

Meters

• PWM compatible voltmeter

• Clamp-on ammeter

Additional tools

• 1000 v Insulation tester

• Laptop with system software

• Cell phone

• Oscilloscope (with Isolated case)

First thing

• Do not apply power until you

complete the static tests

The Troubleshooting approach

• Take the logical approach

– Take it all in

Use all you senses

Perform physical inspection

Do a process of elimination

Make alignment with sequence of operation

Align with what is to what should be

– What does the display tell you

– check the programing

– How does the drive look on the inside

Check it out

• Installation

• Connection

• Environment

• Fuses

• Burnt marks or smell

VFD sections

• Regulator—Controls the rectifier and inverter to

produce the desired ac frequency and voltage.

• Rectifier—Converts the fixed 60 Hz ac voltage input

to dc.

• Inverter—Switches the rectified dc voltage to ac,

creating variable ac frequency (and controlling

current flow, if desired).

• VFDs convert AC to DC…then DC to AC

(at varying frequency and voltage)

460 V, 60 Hz 640 V, DC 307 V, 40 Hz

AC DC AC

Rectifier Inverter

VFD Introduction

VFDs allow the motor to operate and consume electricity as if it

were the right sized horsepower for the job.

TROUBLESHOOTING THE DRIVE THAT WORKS IN HAND MODE.

• Before moving on try taking a voltage and current

reading on the input and output of the drive. Both

should be balanced. The output voltage must be

balanced within a volt phase to phase with the motor

connected.

Questions to Ask About the Problem.

• Did the motor ever run?

• Did it have problems when it was running?

• What changed since it did run?

• Is the problem repeatable?

• Does the problem always happen at the same time or

with consistent repeatability?

DOES THE DRIVE RUN THE

MOTOR IN HAND?

DOES THE DRIVE RUN THE MOTOR IN HAND?

• At this point try to run the motor using the hand

start function of the drive.

• Press the hand start key and slowly begin to

increase the speed of the motor by pressing the

plus key.

TROUBLESHOOTING THE DRIVE THAT WORKS IN HAND MODE.

• If the drive works the motor up and down in speed

when in the hand mode, the drive is probably good.

Questions to Ask About the Problem.

• Did the motor ever run?

• Did it have problems when it was running?

• What changed since it did run?

• Is the problem repeatable?

• Does the problem always happen at the

same time or with consistent repeatability?

DOES THE DRIVE RUN THE

MOTOR IN HAND?

The Motor Won’t Run in Bypass Is there power to the bypass?

– Are the main or bypass fuses OK?

– Is the safety interlock closed? (TB1: 1 & 2)

– Is the motor overload tripped?

– Is the motor connected?

– For some drives: Is the building automation

system giving a run command? (TB1: 2 & 3) (Use the customer connection diagram and bypass schematic for the

drive to determine this.)

DIVIDE AND CONQUER Where Is the Problem?

NOTE!

• If the motor will not run in the drive mode or

the drive is dead, before trying the bypass

mode, MEGGER the motor and the wiring

from the output of the drive or bypass first

before continuing the process of

troubleshooting!!!!

HOW TO MEGGER A MOTOR

Motor wiring

Know your motor wiring

Position A B C

T0 ++ - -

T1 + + - -

T2 - ++ -

T3 - - + +

T4 - - ++

T5 + - - +

T6 ++ - -

DIVIDE AND CONQUER Where Is the Problem?

• NOTE! • If the motor will not run in the drive mode or

the drive is dead, before trying the bypass mode, MEGGER the motor and the wiring from the output of the drive or bypass first before continuing the process of troubleshooting!!!!

HOW TO MEGGER A MOTOR

TWO MODES OF FAILURE:

WINDING FAILURE

BEARING FAILURE

MOTOR PROBLEMS

MOTOR PROBLEMS

Coil Breakdown at the

point of exit from the

core

COIL FAILURES

Coil Breakdown at the

crown point due to high

voltage spiking.

MOTOR PROBLEMS

Ground Fault failure at the core.

MOTOR PROBLEMS Complete coil failure due

to all or partial loss of

phase.

MOTOR PROBLEMS

BEARING FAILURES

DUE TO POSSIBLE

DRIVE RELATE

PROBLEMS

BEARING FLUTING

CAUSED BY

ELECTROSTATIC

DISCHARGE

42

= 460 VAC

60Hz

Electric Motor Design

Most electric induction motors were designed for operation on 3 phase sign wave power – either 50 or 60 Hz.

The input power was balanced in frequency, phase (120 degrees apart) and in amplitude.

Common mode voltage – the sum of the 3 phases would always equal zero volts.

43

+

Electric Motor Operation by VFD

When operated by VFD, the power to the motor is a series of pulses instead of a smooth sign wave.

The input power is never balanced because the voltage is either 0 volts, positive, or negative with rapid switching between pulses.

The Three phases of voltage pulses ensures that the common mode voltage is never equal to zero and instead is a “square wave” or “6 step” voltage.

=

44

Shaft Voltage Readings

PWM Drives Cause

1. High frequency transients (dv/dt) can break down the insulation between windings and cause corona discharge arcing which can short out the windings.

2. Because of the inherent voltage imbalance and dv/dt, the voltage pulses are capacitively induced on the motor shaft and can overcome the dielectric of the oil film in the motor bearings. Electrical discharges result in pitting and fluting damage in the bearing, breakdown of lubrication, and fluting failure of the bearing.

46

Motor Reliability for Inverter Driven Motors

Motor Winding Problems The motor winding insulation was changed to withstand the transient voltages and to prevent the corona discharges. NEMA MG1 specified motor design to meet what was known as “class F, G or H” insulation, and “corona resistant wire” was developed.

The problem of electrical bearing damage was identified in the NEMA MG1 with for motors above and below NEMA frames

NEMA recommended to use either ceramic bearings or shaft grounding. Shaft grounding also protects attached equipment.

Stator

Rotor

Groun

d

VF

D D

rive

VFD Induced Voltages

VFD induced capacitive voltages from the high switching speed of the pulse

width modulation (PWM) drives discharge through motor bearings and cause

electrical discharge machining (EDM) effect in the bearing race.

Rotor ground currents generated by PWM Drive will partly flow as rotor

ground current through the bearings of the motor. These currents are caused

by the rotor being connected to common ground with a significantly lower

impedance path then the ground of the stator housing.

VFD Induced Shaft Voltages and Bearing

Currents in AC Motors

Shaft

Groun

d

Groun

d

Motors below 500 Frame (NEMA 56 to 449T):

More recently…potentially destructive bearing currents have occasionally occurred in much smaller motors… These drives can be generators of a common mode voltage which…oscillates at high frequency and is capacitively coupled to the rotor. This results in peak pulses as high as 10-40 volts from shaft to ground… Interruption of this current therefore requires insulating both bearings.

Alternately, shaft grounding brushes may be used to divert the current around the bearing.

It should be noted that insulating the motor bearings will not prevent the damage of other shaft connected equipment.

NEMA MG1 section 31.4.4.3

High Frequency Circulating Currents in Large AC, DC Motors & Generators

Stator

Rotor

Groun

d

Shaft Currents

Induced by the magnetic flux imbalance around the motor shaft from the

stator windings, these currents circulate through the motor bearings.

Circulating currents are a problem in large AC and DC motors of over 100 hp.

Because these currents circulate through the motor via the shaft and

bearings, the current flow must be either broken or an alternate path

established to prevent bearing failures.

Shaft

Groun

d

Groun

d

High Frequency Flux encircling the rotor causing shaft bearing

currents

Large Frame Motors (500 frame or larger): …voltages may be

present under sinusoidal operation and are caused by magnetic

dissymmetry's in the construction of these motors…current

path…is from the motor frame through a bearing to the motor

shaft, down the shaft, and through the other bearing back to the

motor frame. This type of current can be interrupted by insulating

one of the bearings.

NEMA MG1 section 31.4.4.3

When VFD is used, the circulating currents described

above increase from 60 Hz to KHz or MHz frequencies

and may effect motors rated at 150 kW (200 HP). This is

referred to as “High Frequency Circulating Current” Reference: A. Muetze, A. Binder, H. Vogel, J. Hering, “What can bearings bear? – How much

current is too much? How much current reduction enough?” IEEE Magazine on

Industry Applications, vol. 12, no. 6, pp. 57-64, November/December 2006.

Bearing Failure

March 2005 Journal of Electrostatics “Statistical model of electrostatic discharge hazard in bearings of induction motor fed by inverter” by Adam Kempski et. al. “Electrical Discharge Machining (EDM) bearing currents have been found as the main cause of premature bearing damages in Pulse Width Modulation (PWM) inverter fed drives.”

February 2007: Pump and Systems Magazine “How to Prevent Electrical Erosion in Bearings” by Daniel R. Snyder, P.E., SKF USA Inc. “An estimated 50 percent of all electric motor failures are attributed to bearings, but the bearings themselves are not usually the root cause. Other forces are at work, such as the increasingly common problem of stray currents.”

52

Motor Bearing Damage from Electrical Currents

Electrical Discharge Machining (EDM)

Bearing Pitting Damage

Bearing Fluting Damage

Electron Microscope

(SEM) Image

EDM Pitting

1000x Magnified

EDM Pit

53

Mitigation Strategies

Ground the shaft with spring loaded

brush

– Copper phosphor or bronze metal

brush

– Carbon block brush

Isolate the shaft from the frame of the

motor

- Use insulated sleeve on the

bearing journal

- Replace steel bearings with

ceramic bearings

54

New Conductive Microfiber Shaft GroundingTechnology

Uses several methods to transfer

electrical currents*

*IEEE paper, September 2007: Design Aspects of Conductive Microfiber Rings for Shaft

Grounding Purposes, by Dr. Annette Muetze et. Al.

Direct Contact

Conduction

Electrical Contact without

mechanical contact by

field emission

55

●“Shaft run-out” is

compensated by spring

load

● Material Wear (not

suitable at high

surface rate)

● Vibration due to “stick-

slip”

●Not effective above 2MHz

signal

● Installation Difficulty

●No Spring load

●Negligible wear of micro-

fibers even high surface rate

●Continuous contact despite

“shaft run-out”

●Easy Installation

●Low cost

●Maintenance Free

Within the elastic

limit

New Approach to Electrical Current Transfer

Unique Characteristics

Encircles complete 360 degree shaft area

Unaffected by dirt and grease providing continuous grounding

No maintenance required after installation

56

Shaft Grounding Ring Construction

Conductive

Micro Fibers

Shaft Grounding Ring Bearing Current Mitigation motors to 100 HP

Stator

Rotor Shaft

V

F

D

Ground

EST-ITW

Copyright

2009 –

AEGIS™

Patented

Technolog

y

58

Large Low and Medium Voltage

Motors over 100 HP

Stator

Rotor Shaft

Ground

V

F

D

SKF Insocoat bearing

bearing NDE

AEGIS Shaft Grounding Ring on DE

MOTOR PROBLEMS

One possible fix.

MOTOR PROBLEMS

TRY GOOD HIGH FREQUENCY GROUNDING

TECHNIQUES

MOTOR PROBLEMS

OTHER WAYS TO CORRECT THE PROBLEM

FARADAY SHIELDED

MOTOR INSULATED BEARINGS

MOTOR PROBLEMS

SHAFT GROUNDING SYSTEM OUTPUT FILTERS

The number one killer of electric

motors is heat. Motors that run on

variable frequency drives run hotter

than motors that run across the line.

Voltage spikes can cause problems.

Some drive manufactures are better

at suppressing the spikes than

others.

Premium efficient motors run cooler

than standard general purpose

motors

The Motor Won’t Run in Bypass

•IS THERE POWER TO

THE BYPASS?

•SAFETY

INTERLOCK?

•OVERLOAD?

START/STOP

If the Drive Blows Power Fuses • Before plugging in another fuse ...

• With power off, use the ohmmeter to check for input AND output shorts – Line-to-bus and motor-to-bus, is desirable.

– Line-to-line if the bus connections aren’t readily available

Check programing Example: Trane TR-200 Series Start-Up

1. Parameter 1-03, TORQUE CHARACTERISTICS (For single motor

applications factory default is ok - AUTO ENERGY OPTIMUM. VT. For

multiple motors change to VARIABLE TORQUE.)

2. Parameter 1-20 kW or 1-21 HP, MOTOR POWER parameter 0-03 will

determine if parameter 1-20 –OR- parameter 1-21 is accessible, other

parameter is hidden

3. Parameter 1-22, MOTOR VOLTAGE

4. Parameter 1-23, MOTOR FREQUENCY

5. Parameter 1-24, MOTOR CURRENT

6. Parameter 1-25, MOTOR SPEED

7. Parameter 1-29, run AUTOMATIC MOTOR ADAPTATION

Start-Up Continued

1. Parameter 4-12, MIN. FREQUENCY (6Hz for fans, 18Hz for pumps)

2. Parameter 4-14, MAX. FREQUENCY (typically set to 60Hz)

3. Parameter 3-41, RAMP 1 UP TIME (60 sec for fans, 10 sec for pumps

4. Parameter 3-42, RAMP 1 DOWN TIME (60 sec for fans, 10 sec for pumps)

5. Parameter 5-12, COAST INVERSE (sets function of Terminal 27 – set to

NO OPERATION if external signal not required)

Drive Layout

Input PWR

Quality

Output

Period, range of q Diode Pair in conduction

30o to 90o D1 and D6

90o to 150o D1 and D2

150o to 210o D2 and D3

210o to 270o D3 and D4

270o to 330o D4 and D5

330o to 360o and 0o to 30o D5 and D6

//upload.wikimedia.org/wikipedia/commons/d/d0/PWM_VFD_Waveform.png

Magic Component's

• Regulator

– Electronic controls

– Filters

– Lots of Magic in the boxes which in realty is just

electronics switching between 0 and 1.

Trane TR200 Variable Frequency Drive ‹#›

• Silicon diode = 0.7v

Schottky diode =

0.3v

Germanium diode =

0.2v

Typical Schottky metals: Ti, Ni, Au, Pt, Pd

PWM Drive: Diode Bridge Rectifier

DCAC Rectifier

PWM Drive Output Waveform

low speed

high speedTime frame and Pulse width controlled by Microprocessor

Types of PWM Drives

• Drives using bipolar transistors use a low carrier

frequency

(1 to 4 kHz).

• Drives Using IGBTs:

– Can use carrier frequencies greater than 10 kHz.

– Some can be switched to use lower carrier frequencies.

TR200 Layout

Input/output Testing

DC buss +

DC buss -

DC Buss Voltage Test

• DC Buss + to DC Buss –

– Input Voltage X1.3 = Minimum at Full load

– Input Voltage X 1.4 = Maximum Full load voltage

VFD Voltage

• A-B, B-C, C-A = Line Imbalance: ± 3%

• U-V, V-W, W-U= Balanced

BASIC ELECTRONIC TROUBLESHOOTING

• Ohm checking the power semiconductors.

• Ohm checking the gate driver circuits.

• Checking the gate driver circuits with a scope.

• Running the motor in hand mode.

Ohm checking the power semiconductors.

Set the ohm meter on either the diode check scale or the 2K

scale if you are using a standard LCD style meter with a 9

volt battery.

Start the process by placing the positive lead of the ohm

meter on the positive bus and then check each input

connection with the negative lead of the ohm meter noting

the value of the reading on each input line connection.

Ohm checking the power semiconductors.

NOTE: When ohm checking the power semiconductors

bus cap charging may be noticed. Do not be alarmed.

This is normal.

Now the ohm meter leads and repeat the process.

Again note the readings. What should be observed if

the power semiconductors are good, is that you will

notice that in one direction the meter readings will be

with in the range of 0.3 to 0.7 K ohms and out of scale in

the opposite direction.

Ohm checking the power semiconductors.

Repeat the same process to check the output

semiconductors. Similar reading should be obtained with

these devices.

With these reading available, determine if the drive has

sustained semiconductor damage and take the appropriate

steps to repair the drive.

Input Testing Meter set to diode test

• Meter + Lead to DC Buss +

– Meter – to L1 ,L2, L3 ≈ ∞ (infinity) (After Charge Cap.)

• Meter - Lead to DC Buss +

– Meter + to L1, L2, L3 ≈ .48

• Meter + Lead to DC Buss –

– Meter – lead to L1, L2, L3 ≈.48

• Meter – lead to DC –

– Meter + lead to L1, L2 L3 ≈ ∞ (infinity) (After Charge Cap.)

Checking the gate driver circuits with a scope.

For those people who have access to an oscilloscope,

below is the scope pattern you will see.

This measurement is only available to you with drives

sized 15 through 75 HP 460 Volt and 5 though 25 HP 208

Volt. Drives smaller and larger do not have access to

the IGBT gate leads.

Drive Layout Input PWR

Quality

Output

• An inductor stores energy in the magnetic field

created by the current.

• When the current through a coil changes and an

induced voltage is created as a result of the changing

magnetic field, the direction of the induced voltage is

such that it always opposes the change in current.

• What reactions do you see in AC or DC .

• DC current

• Back EMF present during DC turn-on until stabilized,

Back EMF present with polarity reversed during DC

turn-off until decay is complete.

• AC current

• Back EMF present alternating in each direction due

to on off action of AC

Inductor Applications

• Coils resist rapid changes in the current flowing

through them.

• Inductors freely pass steady dc current.

Reducing Harmonic Distortion

• DC link reactor

• AC line reactors

DC Link Reactors

AC Line Reactors

Input Reactor’s Effect

Ideal

Distorted

With reactor

Comparison

DC Link Reactors

• Reduces harmonic

distortion

• Built into the drive as

standard

• Requires one or two

coils, can reduce the

size of the bus

capacitor

AC Line Reactors

• Reduces harmonic

distortion

• Extra cost option —

increases the drive’s

size

• Requires three coils

Comparison, continued

DC Link Reactors

• Does not affect the drive’s AC line operating range

• Protects against current surges

• Voltage snubbers in the drive protect against voltage surges

AC Line Reactors

• Reduces the AC voltage supplied to the drive

• Protects against current surges

• Protects against voltage surges

AC Line Reactors

• Drives with no DC link reactors generally require AC

line reactors

– To reduce harmonic distortion

– More importantly, to keep the drive from being

damaged by power line disturbances

Combining DC and AC Reactors

• Why not combine both?

• Typical example: (from drivesmag.com) – no reactors

62% current distortion

– 3% AC reactor 37% current distortion

– 3% DC reactor 31% current distortion

– 3% DC reactor + 3% AC reactor 28% current distortion

This isn’t

cost

effective!

Reducing Harmonic Distortion

• DC link reactor

• AC line reactors

• Harmonic traps

• 12-pulse input

• Active filters

Harmonic Traps

• Designed to “trap”

specific harmonic

• Specially designed

for the individual

building

• Often applied once,

at the point of

common coupling of

all building power

D-Y transformer

to the rest of the drive

12-Pulse Input

• Eliminates the 5th and 7th harmonics

• Needs a D-Y transformer and two rectifiers

• The transformer – is expensive

– probably isn’t supplied by the drive manufacturer

Active Filter

• How it works

– Electronically monitors the AC power line

– Switches power from or to the line based on the

line’s condition

• Concerns

– Expensive

– Complex

– Adds high frequency noise (EMI and RFI) to the

building

Capacitors Pass

A.C.

Capacitors

Block D.C.

CAPACITOR

A capacitor is an electronic device which consists of

two plates separated by some type of insulator. A

capacitor's value is commonly referred to in

microfarads, one millionth of a farad. It is expressed in

micro farads because the farad is such a large value of

capacitance.

When a DC voltage source is applied to the capacitor there is an initial

surge of current, then the current stops. When the current stops flowing,

the capacitor is in a charged state. If the DC source is removed from the

capacitor, the capacitor will retain a voltage across its terminals. This

charge can be discharged by connecting the plates together. Generally, if

an AC voltage source is connected across the capacitor, the current will

flow through the capacitor until the source is removed. The exceptions

to the situation, where an AC voltage is applied to a capacitor, are going

to be explained later.

Capacitors How much is it???

• Parallel Circuit

• Ct=C1+C2

• Series Circuits

• For 2 Capacitors Ct=(C1xC2)/(C1+C2)

• For more than 2 capacitors in series

• Ct=(1)/((1/C1)+(1/C2)+(1/C3))etc.

Capacitor Applications

• Power supply filters

• Spike Remover

• AC-DC Selective filter

• A Capacitor will pass the Fluctuation signal and

completely block the steady DC level.

• DC BUSS CAPACITORS:

THE GOOD, THE BAD, AND THE UGLY!

Drive Layout Input PWR

Quality

Output

The bipolar junction transistor consists of three layers

of highly purified silicon (or germanium) to which small

amounts of boron (p-type) or phosphorus (n-type) have

been added. The boundary between each layer forms a

junction, which only allows current to flow from p to n.

Connections to each layer are made by evaporating

aluminum on the surface; the silicon dioxide coating

protects the nonmetalized areas. A small current

through the base-emitter junction causes a current 10

to 1000 times larger to flow between the collector and

emitter. (The arrows show a positive current; the

names of layers should not be taken literally.) The

many uses of the junction transistor, from sensitive

electronic detectors to powerful hi-fi amplifiers, all

depend on this current amplification.

© Microsoft Corporation. All Rights Reserved.

"Bipolar Junction Transistors," Microsoft®

Encarta® Encyclopedia 99. © 1993-1998 Microsoft

Corporation. All rights reserved.

IGBT

• There are 2 Count them 2

IGBT’S In Each module used

in our VFD’s

Input/output test

• Setup

– Test for no input/output or DC bus voltage.

– Input and output drive wiring disconnected

– Set meter to Diode function

– Find Test Points (DC+, DC-, L1,L2,L3, U,V,W)

Input Testing

• Meter + Lead to DC Buss +

– Meter – to U, V, W ≈ ∞ (infinity) (After Charge Cap.)

• Meter - Lead to DC Buss +

– Meter – to U,V, W ≈ .39

• Meter + lead to DC Buss –

– Meter – Lead to U, V, W ≈ .39

• Meter – Lead to DC Buss –

– Meter + lead U, V, W ≈ ∞ (infinity) (After Charge Cap.)

Input Testing

• Meter + Lead to DC Buss -

– Meter – to L1 – L3 ≈.48

– Meter – to U – V ≈ .39

• Meter - Lead to DC Buss –

– Meter – to L1, L2, L3 ≈ ∞ (infinity) (After Charge Cap.)

– Meter – to U,V, W ≈ ∞ (infinity) (After Charge Cap.)

VFD Voltage

• A-B, B-C, C-A = Line Imbalance: ± 3%

• U-V, V-W, W-U= Balanced

Drive Control

Control

• Communication protocols

• Inputs and outputs

– Binary or digital AC or DC example: (0-24VDC, open

or closed)

– Analog example: (4-20 ma 0-10 VDC, 0-5 VDC)

OPTO-COUPLER

EEPROM Electrically erasable programmable ROM

With normal ROMs you have to replace the chip (or

chips) when new BIOS instructions are introduced.

With EEPROMs, a program tells the chip's controller

to give it electronic amnesia and then downloads the

new BIOS code into it. This means a manufacturer

can easily distribute BIOS updates on floppy, for

instance. This feature is also called flash BIOS, and

you might also come across it in devices like

modems and graphics/video cards.

Checking the gate driver circuits with a scope.

For those people who have access to an oscilloscope, below is

the scope pattern you will see.

This measurement is only available to you with drives sized 15

through 75 HP 460 Volt and 5 though 25 HP 208 Volt. Drives

smaller and larger do not have access to the IGBT gate leads.

Safety Stop

TR-200

Fault Relay

240 V AC, 2 A

Analog

Inputs and

Outputs

Digital Inputs

12 & 18: Run Command

12 & 27: Interlock

(MUST be Connected to 24

V supply)

RS-485

Run Relay

30 V AC, 1 A

Wiring the Drive

• Control Wiring

• Terminal blocks

can be unplugged

Digital Inputs:

12 & 27: Interlock

(MUST be Connected to

24 V supply)

Wiring the Drive

• Control Wiring

• Terminal

blocks can be

unplugged

Plus 24 VDC

Safety Contact

Fire / Freeze / Etc.

Parameter 304 ( Coast Inverse)

Display reads “UN READY” in

lower right corner.

Digital Inputs:

12 & 18 (Start / Stop)

(MUST be Connected to

24 V supply)

Wiring the Drive

• Control Wiring

• Terminal

blocks can be

unplugged

Plus 24 VDC

Start Command From Automation

Parameter 302 ( Start )

Note: When Contact Opens Unit Ramps to a Stop

Wiring the Drive

• Control Wiring

• Terminal

blocks can be

unplugged

Drive Fault Indication

Use Terminals 01 and 03

Registers a Drive Fault if not Powered up

Terminal Block Located under Power Terminals

Drive Run Indication

Contacts are Low Voltage ( 30 VAC)

Signals Automation Drive is Running

Parameter 326

(No Alarm)

Parameter 323

(Running)

Wiring the Drive

• Control Wiring

• Terminal

blocks can be

unplugged

Positive Voltage scaled 0 to 10 VDC

Analog Input 53

Para 308 ( Reference)

Para 309 (Low Scaling) 0 VDC

Para 310 ( High Scaling) 10 VDC

Common for Input Follower Signal

Para 314

Terminal 60 Function set for (No Operation)

FROM AUTOMATION

Trane TR200 Variable Frequency Drive ‹#›

Analog Inputs Term 530-10 V

Term 540-10 V

Term 604-20 mA

FUNCTION * 308 311 314

SCALE LOW 309 312 315

SCALE HIGH 310 313 316

* Set the FUNCTION of the terminal used for speed

control to REFERENCE.

Set the FUNCTION of unused terminals to NO

OPERATION.

Open Loop

Note: All Trane drives have term 53 set for

default as Reference & 0-10 VDC

VFD testing

By Pass Contactors