Hypertherm HT4400 HySpeed Plasma Arc Cutting System - Manual (Page 131)

MAINTENANCE
HT4400 Instruction Manual 5-41
7
High-frequency console (if applicable)
20. Open the cover and inspect the interior for condensation or the accumulation of dust and particulates. If dust
and particulates are present, blow out the unit with compressed air. If moisture is present, dry the inside of the
console with a cloth and contact Hypertherm Technical Service for recommended action.
21. Inspect the spark gap subassembly. Inspect the 3 electrodes. Verify that the electrodes are 0.508 mm (0.020")
apart and that they are clean and the ends are flat. File the electrodes clean with a diamond file if necessary.
Ensure that the wiring connections to the spark gap subassembly are secure. Check that the console doors
are properly closed.
22. Inspect the torch leads. Ensure that they are fastened tightly to the outside of the high-frequency console.
System grounding
23. Verify that all components of the system are individually grounded to a driven earth ground, as described in the
instruction manual.
A. All metal enclosures, such as the power supply, high-frequency console and gas console, should be
connected individually to a ground point. These connections should be made with 10 mm2 (#8 AWG) wire
(USA), or equivalent-size wire.
24. Check the connection from the cutting table to the workpiece (+) lead. Particularly inspect where the positive
(+) lead connects to the cutting table to ensure that it is a good, clean connection. A poor connection may
cause arc transfer problems.