CEBORA S.p.A.
14
3.302.089
31/05/02
Correct?
Correct?
Correct?
3.3.6
- Gas flows from the torch, the pilot arc does not light (high frequency missing).
NOTE
Some of the following tests may be checked only in the second after pressing the torch start
button, due to failure by the pilot arc to strike.
HF OSCILLATOR TEST.
q
HF board (22), discharger SC1 discharges at regular intervals, for approximately one second,
with start button pressed.
NO
YES
♦
Check connections between HF board (22) and torch; more specifically, between
TP5 and the torch electrode conductor, terminal E of J6 and nozzle conductor.
♦
Check torch cable; if worn or damaged or losing its insulation, replace.
♦
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 the operation of the pressure regulator (E) and pressure gauge
(F), and observe the technical specifications (see Instructions Manual).
♦
Go to par. 3.3.7.
♦
Check the distance between the tips of the discharger SC1 (correct value = 0.9 mm.).
♦
Make sure the HF transformer (T2) is correctly fixed on HF board (22), especially that the
primary winding is not interrupted. If necessary reset the original connection or replace HF
board (22).
WARNING
FOR THE FOLLOWING TESTS
DISCONNECT THE CONNECTOR J3
ON THE HF
BOARD (22) TO PREVENT HIGH FREQUENCY FROM BEING GENERATED.
CONTACT TIP VOLTAGE TEST.
q
HF board (22), connector J6-E and TP5 (gnd) = fig. 5.2.1, with start button pressed (open
circuit nozzle voltage, interrupted after approximately 300 msec., for missing pilot arc
current).
YES
NO
♦
Go to par. 3.3.7.
HF BOARD (22) POWER SUPPLY TEST.
q
HF board (22), connector J4 and patch terminal disconnected from J3 (gnd) = fig. 5.2.2, with
start button pressed (HF board (22) power supply voltage, interrupted after approximately 300
msec., for missing pilot arc current).
YES
NO
♦
Check the wiring between J3 and J4 HF board (22) and transformer TF2 on power
board (35).
