Isolated Analog Output Signal Conditioner - Externally Sourced?

[jkelleyus]

All,

This should be easy but I'm finding it difficult.

I have an older OEM piece of equipment that I need to send a 0-5 vdc analog command signal to... this signal must be sourced from the OEM piece.

Having looked at a bunch of supplier sites it appears all of them source their own 0-10 vdc. Does anyone know of a supplier which allows the output source to be external to the device?

Any help is appreciated.

Thanks,

John

 

[Plastic]

Action Instruments

Slim Pak
DC to DC analog isolator

Field configurable

 

[shooter]

or use two resistors.
or i do not understand what the problem is?

 

[bernie_carlton]

I could see the need if the end device occasionally turns off (or otherwise modifies) its power source thus expecting the input to change. But the commons would have to be connected anyway.

Otherwise, voltage is voltage. With the commons are connected I don't see how it would matter to the end device.

 

[jkelleyus]

Thanks, everyone. The OEM was the one insisting the vdc had to be sourced from the equipment side. I do see the point that voltage is voltage, but sometimes vendors played tricks with their early control equipment. This piece is a mid 90's induction furnace power supply and the control is based on a Z80 microprocessor board. I'm just trying to be as careful as possible here.....

I'll probably get back to this over the weekend and do some extensive testing with my handy Fluke. At this point I'm not sure why I couldn't just use the 0-10 vdc from my Micrologix 1762-IF2OF2. Tie the commons, send the 0-5 vdc command and go?

Any thoughts?

Thanks again,

John

 

[jdbrandt]

Phoenix Contact also makes some 2-way and 3-way isolated transmitters.