Retransmitting and Isolating 4-20mA Signals from Remotely-Mounted 3-Wire Gas Detection Sensors
Defining the Problem:
Typically, signals from 3-wire remote sensors monitoring combustible and toxic gases are transmitted directly to the remote gas monitor or controller. However, there are cases when it is desirable to send the signal to more than one destination. This can either be accomplished by retransmitting the existing signal to additional locations or by completely isolating the signal and then sending it to multiple locations.
A 3-wire remotely-mounted gas detection sensor which transmits a 4-20mA signal. It is important to note that a 3-wire loop is where the sensor and receiver share a ground connection with power, and the sensor uses a third wire to connect to power outside the current loop. You can use either 2-wire (or 4-wire) isolators to retransmit the loop to a 2-wire (or 4-wire) splitter for complete isolation of the output(s).
|Implementing the Solution:||Featured Products:|
Gas detectors are usually installed in hazardous areas. These isolators and splitters are designed for UL/cUL Class 1 Division 2 safety rating for hazardous environments. These transmitter’s default configuration is for 4-20mA input and output making installation simple and with up to 1500V of isolation the protection is excellent.
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