Thermal Dynamics PAK Master 150XL, Руководство по обслуживанию

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SERVICE TROUBLESHOOTING 4-12 Manual 0-2728
B. When operating at amperages over 35 amps the
amperage drops off after main cutting arc initiates
Check whether Drag indicator (D31) on the Logic PC
Board is ON when the torch tip comes in contact with
the workpiece.
1. Cutting tip in contact with the workpiece.
a. Maintain standoff distance 1/8"-3/8" between
cutting tip and workpiece.
2. Faulty Logic PC Board
If torch tip is off the workpiece and the drag indi-
cator, D31, on the Logic PC Board is still ON, then
replace the Logic PC Board.
C. Main cutting arc will not shut off when torch
signal is deactivated
1. STANDARD/LATCH Switch in LATCH position
a. Place switch to STANDARD position.
2. Faulty STANDARD/LATCH Switch
a. Test switch for open condition when in STAN-
DARD position and replace if necessary.
3. Faulty Logic PC Board or Wiring Harness
Disconnect STANDARD/LATCH Switch from
wiring harness at J28 and retest system.
• If main arc will shut off, then Logic PC Board
is faulty.
• If main arc will still not shut off, then wiring
harness is faulty. Repair as necessary.
4.10 Test Procedures
The test procedures in this subsection are referenced in
the troubleshooting section.
A. Safety Precautions
1. Significant DC voltage exists after removal of input
power. Allow 2 minutes for discharge time. Voltage
measured on input capacitors must be zero before
performing service on the power supply.
2. Do Not touch electrical components with any part of
the human body when power is applied.
3. Keep away from any moving parts.
4. Hot surfaces can cause severe burns. Allow equip-
ment to cool before servicing.
5. Electrostatic discharge can damage printed circuit
board assemblies. Transport printed circuit boards in
proper anti-static shielded packages. Use proper
grounding techniques with wrist strap before handling
printed circuit boards.
6. Misaligned plugs can cause printed circuit board dam-
age. Be sure plugs are properly aligned and com-
pletely seated.
7. Excessive pressure can damage printed circuit board.
Use only minimal pressure and gentle movement
when disconnecting or connecting printed circuit
board plugs.
B. Opening Power Supply Enclosure
The left side panel of the Power Supply must be removed
to gain access to the input power connections and the
input voltage selection.
WARNING
Disconnect primary power at the source before as-
sembling or disassembling the Power Supply, torch
parts, or torch and leads assemblies.
1. Remove input power from the unit.
2. Loosen the two bottom screws in the slotted holes of
the desired Side Panel (viewed from the front of the
unit).
3. Remove the remaining screws which secure the Side
Panel to the Power Supply.
A-03058
NOTE
Art may differ
from actual unit.