Tweco 1000 Merlin(Sept1999) - Manual (Page 46)

SERVICE 42 Manual 0-2731
• If red LED is ON proceed to Step 15.
• If red LED is OFF proceed to Step 6
6. Remove connector J1 from the Arc Starter PC Board
and reconnect making a good connection.
7. On the Arc Starter PC Board check the red LED indica-
tor.
• If red LED is ON proceed to Step 15.
• If red LED is OFF proceed to Step 8
8. Remove connector J1 from the Arc Starter PC Board.
9. Measure for 36 VAC between J1-1 and J1-3 on the con-
nector.
• If 36 VAC is at the connector, Arc Starter PC Board
is defective.
• If 36 VAC is not present at J1 proceed to Step 10.
10. Place the RUN/SET switch on the Power Supply to
the RUN position.
11. Place the main power switch on front panel of the
Power Supply to OFF.
12. Remove the Remote Arc Starter Control Cable from
the bulkhead connection, J14, at the front panel of the
Power Supply.
13. Turn the main power switch on the front of the Power
Supply to ON.
14. Check for 36 VAC between pins 5 and 8 of the Torch
Control connector (J14) at the Power Supply bulkhead.
NOTE
Refer to the Power Supply Operating and Service
manuals for more details.
• If not present, problem is in the Power Supply.
• If present, check for open in Torch Supply Leads
Assembly signal wires.
15. If the Arc Starter PC Board 36 VAC red LED was ON
from the test in Step 5 or 9, place RUN/SET to RUN
position.
16. Press start and go through a start sequence. After
pre-flow the DC indicator is ON. When the Power
Supply is activated and the DC indicator is ON, there
should be greater than 220 VDC between the torch
tip (+) and electrode (-).
WARNING
High voltage (300-400vdc) is present in Remote
Arc Starter.
17. Measure between E1(+) and E2 (-) on the Arc Starter
PC Board.
WARNING
DO NOT accidently measure P1 and P2, studs
and brass nuts, where the CD Transformer (T1)
connects to the Arc Starter PC Board.
• If voltage more than 220 VDC is present Arc Starter
PC Board is defective.
NOTE
A dirty or incorrect gap in spark gap could cause
the same problem. Gap should be 0.015 +/- 0.001"
and is not adjustable.
• If voltage is less than 220 VDC, proceed to Step 18.
18. In the Power Supply measure the DC voltage between
the negative power lead and the red pilot lead.
• If greater than 220 VDC, check for open connec-
tions through the Power Supply connections, Torch
Supply Leads Assembly, and Remote Arc Starter
input and output connections.
• If less than 220 VDC, can be caused by a shorted
torch or torch leads.
• No voltage can be caused by the Pilot Control (PCR)
contactor in the Power Supply not closing. Refer
to the Power Supply Service Manual under symp-
toms of No Pilot.