The power supply consists of the following.
AC input circuit
Transformer
Bias power supply including rectifier, filter, pre-regulator and
reference voltage source
Main regulator circuit including the main rectifier and filter, series
regulator, current comparator, voltage comparator, reference voltage
amplifier, remote device and relay control circuit
The block diagram below shows the circuit arrangement. The single
phase input power is connected to the transformer through the input
circuit. Details of each part are described in the next page.
The auxiliary rectifiers D1011 to D1014 provide bias voltage filtered by
the capacitors C102 and C103, for the pre-regulators U101 and U102.
They provide a regulated voltage for other modules.
The main rectifier is a full wave bridge rectifier. It provides the power
after the rectifier is filtered by the capacitor C101, and then regulated via
a series-wound regulator, which is finally delivered to the output terminal.