Tweco Merlin 3000 Cutting Systems - Manual (Page 21)

Manual 0-2475 17 SERVICE
NOTE
Connector J1 must be connected to the Arc Starter
PC Board.
• 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 24 VAC between J1-1 and J1-3 on the con-
nector.
• If 24 VAC is at the connector, Arc Starter PC Board
is defective.
• If 24 VAC is not present at J1 proceed to Step 10.
10. Place the RUN/SET/PURGE 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 Torch Leads Extension Assembly from
the bulkhead connection 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 24 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.
Check the 24 VAC circuit Fuse F3 (1A, 250V) lo-
cated on a panel above the Main Transformer on
the right side of the Power Supply (facing the front
of unit). Check the fuse and replace as necessary.
If the Fuse (F3) blows again on power up or when
you try to start the pilot, Arc Starter PC Board is
defective.
If Fuse (F3) blows once cutting starts there may
be a short in the OK-To-Move circuit. The same
24 VAC is used for OK-To-Move if selected by SW5
on the Power Supply Logic PC Board. Refer to
the Power Supply Operating Manual for OK-To-
Move options.
Note
If the Remote Control RC6010 is used the 24 VAC
OK-To-Move should not be selected at SW5 in the
Remote Control.
• If present, check for open in Torch Leads Extension
Assembly signal wires.
A-00809
1 2 3 4 5
6 7 8 9
10 11 12 13 14
Signal Connector
Torch (+)
Coolant Return
Secondary
Gas
Torch (-)
Figure 4-1 Signal Connector Pin Location
15. If the Arc Starter PC Board 24 VAC red LED was ON
from the test in Step 5 or 9, place RUN/SET/PURGE
to RUN position.
16. Press start after pre-flow and go through start se-
quence. PILOT and DC LEDs are ON. When the
Power Supply is activated and the DC and PILOT
LED's are ON, there should be greater than 220 VDC
between the torch tip (+) and electrode (-).
WARNING
High voltage (300-400vdc) is present in Arc Starter
Box.
17. Measure between E1(+) and E2 (-) on 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.