Gas Flows From The Torch, The Pilot Arc Does Not Light (Nozzle Voltage Missing) - Cebora PLASMA PROF 80 Service Manual

CEBORA S.p.A.

3.3.6 - Gas flows from the torch, the pilot arc does not light (nozzle voltage missing).

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 a duration of
approximately two seconds (maximum pilot arc time)).
♦ Go to par. 3.3.7.
NOZZLE VOLTAGE TEST.
Terminal J1 of HF-filter board (22) 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)).
♦ Check the condition of the central adapter, the torch cable and torch; especially
make sure there are no short-circuits or insulation leaks between the conductors or
between the contacts of the central adapter. Replace any worn or damaged
components.
♦ Check electrode and torch nozzle; replace if worn or damaged.
♦ Make sure that the gas pressure in the torch plasma chamber is not too high. If
necessary check operation of the pressure regulator (E) and pressure gauge (F)
and adjust in observance of the technical specifications.
♦ Go to par. 3.3.5.
NOZZLE RELAY COMMAND TEST.
Relay board (27), connector J5 = approximately 26 Vac with start button pressed and for a
duration of 2 seconds (maximum pilot arc time).
♦ Check the wiring between J5 HF-filter board (27) and terminals 3 and 9 of J5
control board (9).
♦ Check the condition of the nozzle relay on relay board (27). If you find burnt
contacts or have difficulty moving the mobile unit, replace the relay with a similar
one, or the entire relay board (27).
♦ Replace the relay (27) and/or power (20) and/or control (9) boards.
3.302.167
WARNING
Correct?
YES
Correct?
NO
Correct?
YES
NO
YES
NO
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25/06/04