Answer / carl_ellis

No, it is not possible to convert a 4 wire device (power on
2 wires, output signal on 2 wires) to a 2 wire, loop
powered transmitter.

A 2 wire loop powered transmitter uses 3.7mA of the current
loop to runs its electronics. That's why the 'live zero'
starts at 4.0mA, so that there's some power avialable to
the transmitter's electronics.

There's lots of technologies that cannot run on the limited
power of approximately 3.7mA at 24Vdc. Thermal dispersion
flow meters, most wet cell gas detectors, thermal
ionization detectors, to name a few, which have to be 3 or
4 wire devices in order to have sufficient power to operate.

Carl Ellis
Measure First

Answer / amit

it's function ablavale in transmitter otherwise we do not
convert them.

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