Looking for a signal or pulse stretcher

[gbeaker]

I've got an older PLC that can't always pick up an input pulse from a sensor. The sensor is a pretty standard 24vdc PNP prox. I know I've seen devices to go inline, even with 2 m8 connectors, that will stretch the signal to 250ms or so. Any one have some leads?

 

[dYoast]

If you can change the sensor, Keyence has a pulse stretcher built in.

Otherwise, try Weidmuller or Balluff.

Turck also has some screw in connectors that may have the pulse stretcher. This would connect between the sensor and cable.

 

[Lancie1]

Balluff and Turck for sure have them.

http://www.balluff-ua.com/pdf/KT_PulseExtender_EN.pdf
http://www.turck-usa.com/Products/Sensors/Smart_Plugs/

For the Turck Smart Plug, it would be the SPT1-AP6X Input/Output Delay.

 

[TConnolly]

Is this an older SLC? If so there are some software tricks that might work with an IIM instruction. Can you tell more about the application?

 

[BobB]

You can just use a timer - http://omron.com.au/products/family/2987/specification.html

 

[geniusintraining]

Just use a simple timer.... wire a time off delay to the prox, then you can extend the length of the input

I have a lob on a cam that I was trying use to stop a guillotine knife on top dead center, the lob would flash the input so fast that it was not signaling the input, I found a Siemens multi function timer on the shelf and made it hold the signal longer, worked great

 

[OkiePC]

http://www.clrwtr.com/Weidmuller-JACKPAC.htm

Sometimes a plug in answer is better than a general purpose timer. If you want a precise 50ms or 100ms off delay timer so you can avoid having to alter the panel or specify another spare special sensor with a buttons and a knob to jack with...

 

[BobB]

Timer is fine if set correctly. I have used timers and pulse stretchers in the past - had to use a pulse stretcher with a high speed prox detecting the shaft key on the turbine in a turbo charger on a diesel engine - turbo was running at up to 28000 RPM - interesting!

 

[geniusintraining]

This is similar to what I used

http://support.automation.siemens.com/WW/view/en/27560547/td

I always had a few on the shelf, you never know when you are going to need one... AB, Omron, etc they all make them and they are cheap