Article: KN30029

1) Isolator

2) Transmitter

3) Alarm

4) Transducer

ac Transducer

Terms

Input Signal Powered Isolators

Related APCS Products

Signal Powered Isolator - SPI232
23.5mm wide case.
Two way isolation
No loop voltage required
Dual Signal Powered Isolator - DSI233
23.5mm wide case.
Two way isolation
No loop voltage required
Two independent isolators

Input signal powered isolators derive operating power from the 4-20mA input signal which is isolated, conditioned and sent to the output load.

Circuit loss which is characteristic of input signal powered isolators the two important factors to remember are;

Input drive voltage:
The sensor or transmitter sending the signal to the isolator must be capable of producing more than 9.5V at 20mA output (480Ω load maximum).
Output load range:
The output of the isolator cannot drive into a load of greater than250Ω.

Because Signal powered isolators require no separate power supply, there is minimal effect on the wiring resulting in the lowest installed cost. As long as the input device has sufficient drive.