TABLE OF CONTENTS
0740 800 211 © ESAB AB 2018
READ THIS FIRST.................................................................................... 4
INTRODUCTION....................................................................................... 5
TECHNICAL DATA ................................................................................... 6
WIRING DIAGRAM................................................................................... 11
Component description ......................................................................... 11
LAF 631 – Valid for serial no. 935-xxx-xxxx ......................................... 12
LAF 631 – Valid for serial no. 126-xxx-xxxx up to and including
126-341-xxxx ........................................................................................... 14
LAF 631 – Valid from serial no. 126-342-xxxx ...................................... 16
LAF 1001, LAF 1001M – Valid for serial no. 935-xxx-xxxx .................. 18
LAF 1001, LAF 1001M – Valid for serial no. 126-xxx-xxxx up to and
including 126-341-xxxx .......................................................................... 20
LAF 1001, LAF 1001M – Valid from serial no. 126-342-xxxx ............... 22
LAF 1251, LAF 1251M, LAF 1601, LAF 1601M – Valid for serial no.
935-xxx-xxxx ........................................................................................... 24
LAF 1251, LAF 1251M, LAF 1601, LAF 1601M – Valid for serial no.
126-xxx-xxxx up to and including 126-341-xxxx ................................. 26
LAF 1251, LAF 1251M, LAF 1601, LAF 1601M – Valid from serial no.
126-342-xxxx ........................................................................................... 28
DESCRIPTION OF OPERATION.............................................................. 30
2AP3 Interference suppressor board ................................................... 30
2AP3 Component positions.................................................................. 31
Power sources LAF1001, LAF1001M, LAF1251, LAF1251M,
LAF1601 and LAF1601M ................................................................ 31
Power source LAF631 (from serial no. 744-xxx-xxxx)...................... 31
20AP1 Control board.............................................................................. 31
20AP1:1 Power supply ......................................................................... 32
Voltage monitoring............................................................................. 32
DC supplies, +24V............................................................................. 33
DC supplies, +24V_A ........................................................................ 34
DC supplies, +12V_CAN ................................................................... 34
20AP1:2 Thermal protection................................................................. 35
20AP1:3 Shunt input ............................................................................ 35
20AP1:4 Synchronizing ........................................................................ 36
20AP1:5 Arc voltage............................................................................. 36
20AP1:6 Gate pulses ........................................................................... 37
20AP1:7 CAN bus ................................................................................ 38
CAN power supply............................................................................. 39
20AP1:8 Start / Stop / Weld on............................................................. 39
20AP1:9 Analogue control.................................................................... 40
20AP1:10 Optional I/O ......................................................................... 40