Cebora PLASMA PROF 123 ACC Service Manual page 21

CEBORA S.p.A.
POWER SOURCE OUTPUT CURRENT TRANSDUCER POWER SUPPLY TEST.
Power board (56), connector J3, terminals 2(+) - 3(-) = +15 Vdc; terminals 4(+) - 3(-) = -15
Vdc.
♦ Check the wiring between J3 power board (56) and J3 control board (47).
♦ With Power Source off, temporarily disconnect J3 from power board (56) and
check resistance on terminals 2 and 4 of J3 on power board (56). Correct value =
approximately 2.4 Kohm in both measure directions. If incorrect replace the
power board (56).
♦ Power up the Power Source again, with J3 still disconnected from power board
(56) and check voltage on J3 of control board (47), terminals 2(+) and 3(-) = +15
Vdc; terminals 4(+) and 3(-) = -15 Vdc. If incorrect, replace control board (47).
♦ Check the supply voltages of the control board (47), performing, if necessary, the
CONTROL BOARD (47) POWER SUPPLY TEST of par. 3.3.1.
♦ Replace control board (47) and/or power board (56).
POWER SOURCE OUTPUT CURRENT SIGNAL TEST.
Control board (47), connector J3, terminals 1(+) - 3(gnd) = fig. 5.2.5 (+0.6 Vdc
approximately) Power Source output current feedback signal with pilot arc lit, for 2.5
seconds (pilot arc maximum time), with start button pressed.
♦ Check the wiring between J3 control board (47) and J3 power board (56).
♦ With Power Source off, temporarily disconnect connector J3 from control board
(47) and check resistance between terminals 1 and 3 of J3 on control board (47).
Correct value = 67 ohm. If incorrect, replace control board (47).
♦ Replace control board (47) and/or power board (56).
♦ Check the wiring between output terminal (+) (ground potential) of Power Source and
terminal TP1 of power board (56). If you find loose connections, tighten and replace any
damaged components.
♦ Check the wiring between output terminal (-) (electrode potential) on central adapter (41), HF
transformer (50), choke (35) and terminal TP6 of power board (56). If you find loose
connections, tighten and replace any damaged components.
♦ Replace control board (47) and/or power board (56).
3.302.269
Correct?
YES
Correct?
YES
NO
NO
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12/04/2012