mechanical programmable timers

8/9/2019 Mechanical Programmable Timers

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P R O G RA M

M I N G O F P L

C

N U R D IA NA

N O R D I N


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AGENDA

Mechanical TimingRelays

Timer Instructions

ONDelay ! OFFDelay

Retenti"e Timer

Casca#ing Timer


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Mechanical TimingRelays

Time delay relaysand solid-statetimers are used toprovide a timedelay.•

May have displays, portsor interface for timesettings &electromechanical orsolid state outputs.

• used to activate or de-activate a device after apreset interval of time.


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Mechanica

l

Timing

Relay

$ONDela

y%

Non-timedcontacts are

controlled directlyby the timer coil,as in a general-purpose control

relay.When the coil isenergized, the

timed contactsare prevented

from opening orclosing until the

time delay periodhas elapsed.

Hoever, hen thecoil is de-

energized, thetimed contacts

return

instantaneously totheir normal state


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Time

#

Cont

acts

&ym'ol

!ontact is open

hen relay coil isde-energized

When relay isenergized, there isa time delay in

closing

!ontact is closed

hen relay coil is de-energized

When relay isenergized,there is a time delay

inopening


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Time

#

Cont

acts

&ym'ol

!ontact is normallyopen hen relaycoil is de-energized.

When relay coil isenergized, contact

closes instantly.

When relay coil isde- energized,there is a timedelay before thecontact opens

!ontact is normallyclosed hen relaycoil is de-energized.

When relay coil isenergized, contact

opens instantly.

When relay coil isde- energized, thereis a time delaybefore the contactcloses


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ONDela

y

Relay

Time

r

Circu

it

&e(uence o) O*eration

"# open, T$ de-energized, T$#open, %# is o.

"# closes, T$

energizes, timingperiod starts,T$# still open, %#

is still o.

'fter #( s, T$#

closes, %# issitched on.

"# is opened, T$de-energizes,

T$# opensinstantly, %# issitched o.


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ONDelay Relay

Timer Circuit$NCTO Contact%

"# open, T$ de-energized,T$# closed, %# is on.

"# closes, T$ energizes,timing period starts, T$# isstill closed, %# is still on.

'fter #( s, T$# opens, %# issitched o.

"# is opened, T$ de-energizes, T$# closesinstantly, %# is sitched )N


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O+Delay Relay

Timer Circuit$NOTO Contact%"# open, T$ de-energized,T$# open, %# is o.

"# closes, T$ energizes, T$#

closes instantly, %# issitched on.

"# is opened, T$ de-energizes, timing periodstarts, T$# is still closed, %#is still on.

'fter #( s, T$# opens, %# is

sitched o.


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O+Delay Relay

Timer Circuit $NCTCContact%

"# open, T$ de-energized,T$# closed, %# is on.

"# closes, T$ energizes, T$#opens instantly, %# issitched o.

"# is opened,T$ de-energizes, timing

period starts, T$# is stillopen, %# is still o.

'fter #( s, T$# closes,

%# is sitched on.


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Programme# TimerInstructions

*%! timers areoutput

instructions thatprovide the

same functionsas timing relaysand solid state

timers.

"ome advantages of *%!timers+

Their settings can be alteredeasily

The number of *%! timers usedcan be increased or decreasedby programming changesithout iring changes

The accuracy and repeatabilityare etremely high


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OMRONTimer

a #ecrementing ON#elay timer instructions ,hich re(uirea TIM num'er an# a set "alue $&-%.

TIM/CNT num'ers run )rom 000 through 122. No*re34 is re(uire# ,hen using a TIM/CNT num'er as a#e3ner

Once #e3ne# as a timer5 a TIM/CNT num'er can 'e*re34e# ,ith TIM )or use as an o*eran# in certaininstructions.

The TIM *re34 is use# regar#less o) the timer instructionthat ,as use# to #e3ne the timer.


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OMRONTimerIn OMRON PLC5 Any one

TIM/CNT num'er cannot'e #e3ne# t,ice5 i.e.5

once it has 'een use# asthe #e3ner in any o) the

timer or counter

instructions5 it cannot 'euse# again.

Once #e3ne#5 TIM/CNTnum'ers can 'e use# as

many times as re(uire# aso*eran#s in instructions

other than timer an#counter instructions.


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OMRON 6TIMERTIM7

A timer is acti"ate# ,henits e4ecution con#ition

goes ON an# is reset $to&-% ,hen the e4ecution

con#ition goes OFF. Onceacti"ate#5 TIM measures in

units o) 0.2 secon# )romthe &-.

&- is 'et,een 000.0 an# 888.8.

The #ecimal *oint is not entere#. The EM area is a"aila'le inC9M2:CPU;2 CPU Units only.

Each TIM/CNT num'er can 'euse# as the #e3ner in only one TIMER or COUNTER instruction.


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TIME4ecution

I) the e4ecution con#itionremains ON long enough)or TIM to time #o,n to


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TIMIm*lementation

The timer set "alue must 'e =CD 'et,een >0000 an# >8888.O*eration ,ill 'e as )ollo,s i) >0000 or >0002 is set.

? I) >0000 is set5 the Com*letion Flag ,ill turn ON assoon as the timer@s e4ecution con#ition turns ON.

? I) >0002 is set5 the Com*letion Flag may turn ON assoon as the timer@s e4ecu tion con#ition turns ON 'ecausetimer accuracy is 0 to 0.2 s.

Consi#er the timer accuracy $ 0 to 0.2 s% ,hen #etermining the*ro*er set "alue.


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OMRON:igh &*ee# Timer TIM:$21%

• the same ,ayas TIM e4ce*tthat TIM:

measures inunits o) 0.02secon#

O*eration

• TIM/CNT 000

through TIM/CNT021 shoul# not'e use# in TIM i)they are re(uire#)or TIM:$21%.

Limitation •:ighs*ee# timers ,ithtimer num'ers TIM/CNT000 through TIM/CNT021 ,ill not 'einaccurate ,hen the PC&etu* is set to *er)orminterru*t *rocessing onthese timers.

•:ighs*ee# timers ,ithtimer num'ers TIM/CNT02; through TIM/CNT122 ,ill 'e inaccurate,hen the cycle timee4cee#s 20 ms.

Precaution


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OMRON 6TIM:$21%7

A timer is acti"ate# ,henits e4ecution con#ition

goes ON an# is reset $to&-% ,hen the e4ecution

con#ition goes OFF. Onceacti"ate#5 TIM measures

in units o) 0.2 secon#)rom the &-.

&- is 'et,een 00.00 an# 88.88. $Although00.00 an# 00.02 may 'e set5 00.00 ,ill#isa'le the timer5 i.e.5 turn ON theCom*letion Flag imme#iately5 an# 00.02 is

not relia'ly scanne#.% The #ecimal *oint isnot entere#.

Use TIM/CNT num'ers )rom 000 through 021.:igh s*ee# timers ,ith timer num'ers

TIM/CNT 02; through TIM/CNT 122 shoul#not 'e use# i) the cycle time e4cee#s 20 ms.


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OMRONTIM:$21% usage


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Retenti"e Timer

' retentive timer accumulates timehenever the device receives poer, andmaintains the current time should poerbe removed from the device. )nce thedevice accumulates time eual to itspreset value, the contacts of the devicechange state. The retentive timer must beintentionally reset ith a separate signalfor the accumulated time to be reset.


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Retenti"e Timer


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Retenti"e ONDelay TimingChart


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Retenti"eB Totali


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E4 Retenti"e ONDelay Alarm Program

PRE&&URE &ITC:ONOFF =EFORE

TIMING I& UP TTIM RETAIN P-

PRE&&URE&ITC: ON

UNTIL TIMINGI& UP

ACTI-ATING:ORN


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E4 TimeDelaye# Motor &tarting Program


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A**lication o) Timers

mechanical programmable timers

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