I need to run a signal from a pressure transducer ( 4-20mA ) over a 300m distance before it gets to the analog input on the OPLC. Is this distance too long?
At the moment the transducer supplys an input for a different PLC which is located near the transducer. Can I parallel off this input and run the signal to my V570-57-T20B 300m away ?
If its a matter of using the right size cable then what size would suite ?
You should have no problem running a 4-20 mA signal 300 meters- the voltage drop will be very small and you can ignore it. The problem may by in the other PLC you are connecting to. If the 4-20 input on that PLC is isolated, it will work. Unitronics connects the negative of the analog inputs to the power supply negative (non-isolated), so if your other PLC is non-isolated the signal will end there. You will probably need a loop isolator between the two.