Hypertherm H401 Power Supplies - Manual (Page 27)

INSTALLATION
H401 & H601 Instruction Manual 3-3
5
Grounding Requirements
Proper grounding is essential for personal safety and to prevent emission of high-frequency interference. See the
Appendix section for system grounding requirements.
Connect the worktable to a high-quality earth ground from within 20 feet (6 m) of the table. A suitable ground
consists of a solid copper rod of at least 3/4-inch (19 mm) diameter driven to a depth of at least 8 feet (2.5 m) into
the earth below the permanent moisture level. Ensure that all grounding connections are tight to avoid excessive
heating. See also Grounding in the Safety section. For additional information consult national or local electric
codes.
Noise Levels
Acceptable noise levels as defined by national or local codes may be exceeded by this plasma system. Always
wear proper ear protection when cutting or gouging. See also Noise Protection in the Safety section of this manual.
Power Requirements
All switches, slow-blow fuses and power cables are customer supplied and must be chosen as outlined by
applicable national or local electrical codes. Installation must be performed by a licensed electrician. If
slow-blow fuses are not available or not allowed per applicable codes, use a motor-start circuit breaker.
Power Cables and Fuses
Wire sizes vary based on the distance of the receptacle from the main box. Use a 4-conductor Type SO input
power cable with a conductor temperature rating of 140°F (60°C). The proper strain relief should be used to
prevent damage to input power cables. The cable should be installed only by a licensed electrician. Always connect
the power cable to the power supply before connecting to the line disconnect switch.
Refer to the data tag on the rear of the power supply to verify the correct line voltage requirements and to
determine the continuous current draw for the unit.
Fuse sizes should never exceed the capacity of the power line conductors. Use FRS type fuses.