Answer / carl_ellis

A 230Vac line voltage is converted to an instrumentation
level signal of 0-10Vdc in a converter.

That 0-10Vdc proportional signal is fed into some receiver
which re-transmits the input as a 4-20mA

signal. So now a 0-230Vac signal is a 4-20mA signal.

It isn't clear why the signal was not initially converted to
4-20mA, but that way things are, sometimes.

Carl Ellis
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