In Open Circuit Operation, The Output Voltage Is Not Regular - Cebora PLASMA PROF 80 Service Manual

CEBORA S.p.A.

3.3.7 - In open circuit operation, the output voltage is not regular.

FOR THE FOLLOWING TESTS DISCONNECT THE CONNECTOR J1 ON HF BOARD
(25) TO PREVENT HIGH FREQUENCY FROM BEING GENERATED.
POWER SOURCE OUTPUT VOLTAGE TEST.
Output terminal (H) of the power source and central terminal of the central adapter (12) (gnd)
= fig. 5.2.2, with start button pressed (open-circuit output voltage, for the duration of
approximately two seconds (maximum pilot arc time)).
♦ Open circuit output voltage regular.
POWER BOARD (20) OUTPUT VOLTAGE TEST.
Power board (20), terminals TP4(+) and TP5(-) = fig. 5.2.2, with start button pressed (open-
circuit rectifier output voltage, for a duration of approximately two seconds (maximum pilot
arc time)).
♦ Check the wiring between central adapter (12) central terminal, HF transformer
(23) secondary circuit, choke (44) and terminal TP5 on the power board (20)
(electrode potential), and between output terminal (H) and terminal TP4 on the
power board (20). If you find loose connections, tighten and replace any
components with damaged terminals.
SYNCHRONISM SIGNAL TEST FOR SETTING BOARD (19).
Setting board (19), connector J3, terminals 1 and 3 = terminals 6 and 8 = terminals 10 and 12
= approximately 230 Vac, both with mains at 230 Vac and with mains at 400 Vac (the three
voltages are shifted 120° from one another).
♦ Check the wiring between J3 setting board (19) and voltage change on the
transformer (50). In particular make sure that the connection of each individual
wire has been made as shown in the diagram in par. 5.1.
♦ Replace the transformer (50).
♦ Check the wiring between J1 power board (20) and J5 setting board (19).
♦ Check the presence of voltage at the input to power board (20) by performing the MAINS
CONNECTIONS TEST in par. 3.3.1.
♦ Check the wiring of the transformer (50) secondary circuit with power board (20) and
between J3 of setting board (19) and terminals of the voltage change of the transformer (50).
In particular make sure that the connection of each individual wire has been made as shown in
the diagram in par. 5.1.
3.302.167
WARNING
Correct?
NO
Correct?
NO
Correct?
YES
YES
YES
NO
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25/06/04