Ap2 Analogue Control Board; High Voltage Circuits; Ap2:1H. Voltage Supervision And Pfc Control - ESAB Caddy Mig C200i Service Manual

AP2 Analogue control board

The analogue control PCB contains circuits connected to the input (high voltage,
primary) and circuits connected to the output (low voltage, secondary).

High Voltage Circuits

High voltage circuits (primary side) are placed on the right part of the PCB and they
are connected to the external circuits by means of the connector CN1. High voltage
circuits contains:
S voltage supervision circuits
S PFC control circuits
auxiliary power supply
S
S temperature sensors circuits

AP2:1H. Voltage supervision and PFC control

Voltage supervision circuits senses the DC bus voltage (inputs 19,20 CN1) and the
rectified input voltage (input 15 CN1). As long as voltage are not within limits high
voltage enable line (HV_ENABLE) is grounded by means of transistor Q1.
Operation of the PFC and auxiliary power supply is disabled. The reset IC4 is used
for the voltage control. Two of inputs are connected to the rectified input voltage,
one to the DC bus. Operation of the machine is disabled as long as the a.c. voltage
is less then 188 Vrms or drops under 177 Vrms (SENSE3), and DC bus voltage is
less then 259V or drops below 173V (SENSE1). Another sense input (SENSE2)
has very low time constant along with voltage limitation. It provides fast disable
during the machine switching off.
s1Cad200
- - 13 - -
Edition 101222