Thermal Dynamics SIGNATURE PAK 1250XRTM, Owner'S Manual

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33 SERVICE
The pilot arc should start two seconds after the torch switch is pressed. If it does not, check the
following:
TROUBLE POSSIBLE CAUSE REMEDY
1. Replace PC board
2. Clean and dry area
around high frequency
points, adjust gap (See G,
page 36).
3. Check (See C, page 35).
4. Check (See B, page 35).
5. Check and replace relay if
necessary.
1. Check open circuit voltage
(See F, page 36).
2. Check resistor R6 (See D,
page 35).
3. Repair or replace.
1. Screw electrode into torch
until properly seated.
2. Check and replace if
necessary.
3. Check and replace if
necessary.
4. Check and replace if
necessary.
5. Check and replace if
necessary.
6. Clean and dry lead.
J. No spark in torch or at
spark gap points
K. Spark in torch but no
pilot
L. No spark can be seen in
torch, but spark is present
at spark gap points
TROUBLE POSSIBLE CAUSE REMEDY
M. No cutting arc
1. Faulty time delay circuit
2. High frequency points
shorted
3. Shorted capacitor C10
4. High frequency trans-
former failed
5. Failed relay HF
1. Insufficient DC voltage
2. Pilot resistor failed
3. R.F. suppression coil
broken
1. Electrode shorted against
tip
2. Shorted torch head
3. Failed capacitor C8
4. Broken conductor in torch
lead
5. Shorted torch lead
6. Dirty or wet lead
1. Work cable not connected
2. One leg of power is out 1. Connect.
2. Check T1, T2, and T3
transformer outputs to
main bridge (See H, page
36).
The main cutting arc should start as soon as the torch, with the pilot arc running, is brought to
within 1/8 -3/8 inch (3-10 mm) of the workpiece. If it does not, check:
4.4 TROUBLESHOOTING GUIDE (continued)