input edge

dwpang

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• Apr 16, 2013

• #1

hi anyone can help to explain the meaning of input edge? or how does the input edge occur? the attach pic explains more. thanks.

 

RheinhardtP

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• Apr 16, 2013

• #2

Input terminal on the unit. What type of device is this?

 

dwpang

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• Apr 16, 2013

• #3

hi thanks rhein. its twido software. using schneider electric plc. so input edge basically means a input terminal?

 

LadderLogic

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• Apr 16, 2013

• #4

I think 'input transition' would make a better choice of words here than 'input edge'. A transition, change of state from something to something else.

 

dwpang

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• Apr 16, 2013

• #5

ok.. i still dont quite get it. so as seen from the attached pic, %sw58 occurs when blackout happens right, and the reason is because of this input edge or input transition. so any examples of what can cause this to happen? thanks.

 

Eric Nelson

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• Apr 17, 2013

• #6

I just had a look through the manual (LINK), and on page 463, there is a setting to use a run/stop input.

Maybe your PLC is set up to use an external run/stop command (relay, switch, etc.)?

If it is, then I'm thinking when that input turns off, it will stick a "1" in %SW58.

Some PLCs (DL405 for example) have a connection for an external 'run' contact. This may be something like that.



-Eric

 

dwpang

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• Apr 19, 2013

• #7

oh i understand now. thanks guys!