20Ap2 Relay Board; 20Ap2:1 Power Supply; 20Ap2:2 External Shutdown - ESAB Arc 4000i Service Manual

20AP2 Relay board

The relay board handles hardware--connected inputs and outputs to/from control board
20AP2. The relays provide the necessary galvanic insulation. In the event of a relay fault,
the entire board must be replaced.
20AP2:1 Power supply
The relay board is supplied at +24 V from controller circuit board 20AP1. Link
BY3 tells the processor on the controller board what version of the relay board
is in use.
20AP2:2 External shutdown
Contacts H1 and H2 must be linked if the power source is to work. If there is
no link, the processor and PWM circuit on the control board are disabled.
The H1 -- H2 inputs are used in connection with mechanised welding to
provide On/Off control of the welding power source.
See also the circuit diagram on page 49.
cu19_20_2
- - 42 - -
S0740 800 191/E080229/P78