Cebora SOUND MIG 2035/M Pulse Service Manual page 23

CEBORA S.p.A.
CURRENT TO PRIMARY CIRCUIT OF TRANSFORMER (30) TEST.
Control board (27), connector J4, terminals 3(+) – 4(-) = <0.1 Vdc, current to transformer (30)
primary circuit, with start button pressed, and terminals of the secondary circuit disconnected
from "anode" terminals of diodes (56).
♦ Check the wiring between J4 control board (27) and J6 power board (26).
♦ Make sure that there are no short-circuits in the connections between the primary
circuit of the transformer (30) and terminals TRA1 and TRA2 on power board
(26) (to inspect remove the front ventilation grid).
♦ Check the conditions of the transformer (30). If you notice burn signs or
deformities, replace the transformer (30).
♦ Replace the control (27) and/or power (26) boards.
♦ Replace the transformer (30).
IGBT-DRIVER BOARD COMMAND TEST.
Driver-igbt board, connector J3, terminals 1 and 2 (gnd) = terminals 3 and 4(gnd) = fig. 5.2.2
igbt command signal, with start button pressed, and terminals of the secondary circuit
disconnected from "anode" terminals of diodes (56).
♦ Check the wiring between J3 driver-igbt board and J8 control board (27).
♦ See CONTROL BOARD (27) POWER SUPPLY TEST, par. 3.3.1.
♦ See START COMMAND TEST WITH TRADITIONAL TORCH and START
COMMAND TEST WITH PUSH-PULL TORCH, par. 3.3.4.
♦ Replace the control board (27) and/or driver-igbt board.
♦ Make sure the driver-igbt board is correctly mounted on power board (26).
♦ Check for the presence of 320 Vdc voltage on terminals TP3(+) and TP4(-) on power board
(26). If absent, check for the presence of 230 Vac mains voltage at terminals TP1 and TP2 on
power board (26); if necessary, replace power board (26).
♦ Check the connections between the primary circuit of the transformer (30) and terminals
TRA1 and TRA2 on power board (26) (to inspect, remove the front ventilation grid).
♦ Check the voltage on power board (26), connector J3, terminals 3(+) and 4(-) = +13 Vdc
approx. (end DC-capacitors pre-charge signal). If absent, check the wiring between J3 power
board (26) and J11 control board (27), and check, with power source off and J11 on control
board (27) disconnected, the resistance between the terminals 3 and 4 of J3 power board (26).
Correct value = approximately 400 ohm. If 0 ohm (short-circuit), replace power (26) and
control (27) boards. If >Mohm (circuit broken), replace power board (26).
♦ Check wiring between J2 control board (27) and power source terminals (E)(+) and (F)(-)
(obviously, in the original operating conditions and not the current ones altered for the test).
♦ Replace the power (26) and/or control (27) and/or driver-igbt boards.
♦ Replace the transformer (30).
With power source off reset the dip-switch 2 of SW1 in off position, on control board (27).
3.302.161
Correct?
YES
Correct?
YES
NOTE
NO
NO
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24/03/2004