I can understand 4-20mA signal in a 2-wire loop powered transmitter (transmitter regulate the current in the loop; power supply (say 24VDC) provides the voltage to make that current possible). However, in a 4-wire transmitter, power supply (say 24VDC) is provided to 2 of transmitter terminals...
Big picture question on instrumentaion logic. My existing setup is a single level transmitter (4-20mA) feeding circuit via a controller. To avoid a failure of the circuit, we would like to add a second level transmitter (so that one LT fails, the other will continue to work and feed the...
We have 2 CTs (A and C phase) on the 3-ph motor circuit and the CTs are wired as follows:
1) 2 CTs feed motor protection relays followed by the summated CT (2 CT currents summed before) feeding the motor excitation panel.
We are replacing the motor excitation panel that now requires 2 separate...
