Just stumbled across this forum and hopefully someone can help.
I have a two wire 4-20 ma transmitter connected to an analogue input on a plc.
On rare occasions, using a Fluke process meter, I can "add" approx. one milliamp to the circuit without disconnecting the loop.
I have other uses for the process meter, so I would like to build a cheap circuit, which I can permanently wire in parallel with my analogue input so when I switch it "ON" it will add one ma to the loop.
Any bright ideas ?
I have a two wire 4-20 ma transmitter connected to an analogue input on a plc.
On rare occasions, using a Fluke process meter, I can "add" approx. one milliamp to the circuit without disconnecting the loop.
I have other uses for the process meter, so I would like to build a cheap circuit, which I can permanently wire in parallel with my analogue input so when I switch it "ON" it will add one ma to the loop.
Any bright ideas ?