Ap11, Ap12 Dc Protection Boards - ESAB DTE 255 Service Manual

AP11, AP12 DC protection boards

The high- -speed fuses on the boards protects the IGBT drive circuits on circuit board AP01 in
the event of IGBT failure.
To detect whether a fuse is healthy or blown, measure the resistance at connector XI. With a
healthy fuse, this resistance will be 10kΩ (resistor R1). If the fuse has blown, IGBT module
Q5 has probably also burnt out. Test instructions for the IGBT module are on page 61.
Circuit diagram for circuit boards AP11 and AP12
Component positions for circuit boards AP11 and AP12
- - 55 - -
cdte1de1