Hypertherm HT2000, Instruction Manual

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MAINTENANCE
8-12 HySpeed HT2000
Instruction Manual
19
Problem Possible Causes
/ Solutions
• If there is 120VAC at T1, shut down system and remove
RHF capacitors C3 and C4. (See Figure 9-12 for location
of C3 and C4) Restart system and see if a faint spark is
now observed across the gaps.
• If a spark is not observed at the gaps, replace T1.
If there is a spark, shut down system, and replace
capacitors C3 and C4.
(Always replace the capacitors
in pairs).
4.2. There is no high frequency at the torch.
Check for a shorted torch, a damaged pilot arc lead, or
loose lead connections. Replace the torch or pilot arc lead
or tighten the lead connections.
5. The green POWER ON indicator is
illuminated, the torch START
command is given and the DC ON
indicator illuminates, and there is
high frequency, but there is no
pilot arc.
5.1. Pilot arc relay CR1 is not closing (not getting 120VAC from
the relay board PCB4).
See if the CR1 relay contacts close after the START
command is given. See Figure 9-8 for location of CR1.
If CR1 does not close:
• With an AC voltmeter across the relay, see if 120VAC is
coming from PCB4 after START command is given.
• If there is no 120VAC, check connectors, terminals, pins,
and associated wiring to PCB4.
• If wiring is OK, there is a problem either with PCB4 or
PCB2. See
Section 10
for location of the relay that
controls pilot arc relay CR1.
5.2. Pilot arc relay CR1 is defective.
If there is 120VAC across the relay (see above steps), and
CR1 does not close, replace CR1.
5.3. Main contactor (CON1) or PCB4 is defective.
• With an AC voltmeter, see if contactor CON1 is getting
120VAC after START command is given.