Gas Flows From The Torch, The Pilot Arc Does Not Light (High Frequency Missing) - Cebora PLASMA PROF 164 HQC Service Manual

CEBORA S.p.A.

3.3.7 - Gas flows from the torch, the pilot arc does not light (high frequency missing).

NOZZLE VOLTAGE TEST.
Pilot arc board (58), terminals J5(+) – TP7(-) = approximately +280 Vdc, for a duration of 1
second (maximum pilot arc time) after pressing the start command.
♦ Go to par. 3.3.6.
VOLTAGE PRESENCE TEST ON MODULE HV18.
Module HV18, HF board (2) terminals CN2(+) and CN3(-) = >+200 Vdc (with pilot arc off)
or from +150 to +190 Vdc (with pilot arc lit), for a duration of 1 second (maximum pilot arc
time) after pressing the start command.
♦ Check the wiring between terminals TP3 and J3 of control box board (5) on
module HV18, extension art. 1179 and terminals (53)(-) of the Power Source and
J5(+) on torch board (42). If you find loose connections, tighten and replace any
damaged components.
♦ Make sure the extension art. 1179 is intact.
♦ Check the wiring between terminals TP7 of pilot arc board (58), inductor (24) and
terminal (53) of the Power Source, and between J5 pilot arc board (58), nozzle
resistor (17) and terminal J6 on torch board (42). If you find loose connections,
tighten and replace any damaged components.
♦ Check the continuity between terminals J5 and J6 on torch board (42). If
interrupted, reset the connection.
♦ Check resistor (17). Correct value = 1.3 ohm. Replace if incorrect.
♦ With Power Source off, temporarily disconnect the cables of the extension art.
1179 from the Power Source terminals (53) and J5 of torch board (42), and check
the isolation between the disconnected cables and towards earth. This makes it
possible to test the isolation of extension art. 1197, module HV18 and the torch. If
you find a short-circuit or low resistance, locate and replace the defective
component.
HF OSCILLATOR TEST ON MODULE HV18.
Module HV18, HF board (2), scintillator SCI1 discharges at regular intervals.
♦ Check connections between HF (2) and control box(5) boards in the module
HV18.
♦ Make sure that the connection between CN1 and CN4 of HF board (2) and the
primary circuit of the HF transformer (7) is not interrupted.
♦ Replace the HF (2) and/or control box board (5).
♦ Replace HF transformer (7).
3.302.218
Correct?
YES
Correct?
YES
Correct?
YES
NO
NO
NO
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9/8/2006