ESAB LTR 160, Service Manual

Page: 4 / 46

-- 4 --
cltr0de1
COMPONENT DESCRIPTION
This component description refers to the wiring diagrams for LTR 160 and LTR 200.
The LTR 160/200 are a primary--switched power units, using parallel--connected
MOSFET--transistors as the switching elements. The switching frequency is 36.5 kHz. The
conducting interval varies between zero and 11
µ
s, depending on the welding current output.
The conducting time and frequency are controlled by circuit board AP01.
WARNING !
STATIC ELECTRICITY can damage circuit
boards and electronic components.
S
Observe precautions for handling electrostatic
sensitive devices.
S
Use proper static--proof bags and boxes.
ESD
AP01
The main circuit board with control electronics, see the description on
page 15 and
DESIGN CHANGES
on page 14.
AP02 Circuit board with power transistors for the positive pole,
see description on page 28.
WARNING! the transistors are connected to mains voltage potential.
AP03
Circuit board with power transistors for the negative pole,
see description on page 30.
WARNING! the transistors are connected to mains voltage potential.
AP08
Interference suppression circuit board. Prevents mains--borne interference,
see the circuit diagram on page 34.
AP09 Interference suppression circuit board, remote control connector, see the
circuit diagram on page 35.
AP10
Circuit board with shunt signal amplifier. See the description on page 20.
Included in the LTR 160 from serial number 842--xxx--xxxx. and in the
LTR 200 from serial number 842--902--xxxx.
AP11 HF generator. See the description on page 18.
C01
Transient protection.
C02 Capacitor, 1000
µ
F, buffer/smoothing capacitor. Time to discharge after
turning off the unit: about two minutes.
C03
See C02. Only fitted in the LTR 200.
C04 -- C09
Decoupling capacitors.
C10 2 -- capacitors, 12 nF. Protection against transient voltages. From serial
number 011--xxx--xxxx the capacitors are replaced by L04 and L05.
EV01
Fan, 24 VDC