Hypertherm HT4400 HySpeed Plasma Arc Cutting System - Manual (Page 39)

Rated Input Recommended Recommended
Input Current @ 89 kW Recommended Cable Size (AWG) rated Cable Size (AWG) rated
Voltage Phase Output Slow-Burn Fuse Size for 60° C (140° F) for 90° C (194° F)
200 VAC 3 257 amps 350 amps *See Note below 4/0 AWG
400 VAC 3 128 amps 175 amps 2/0 AWG 2 AWG
440 VAC 3 117 amps 175 amps 2/0 AWG 2 AWG
480 VAC 3 107 amps 150 amps 1 AWG 3 AWG
600 VAC 3 86 amps 125 amps 2 AWG 4 AWG
INSTALLATION
HT4400 Instruction Manual 3-5
2.1
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 with the plasma system. See also Noise Protection in the Safety section of
this manual. See also Appendix D for noise levels measured on the HT4400 system.
Power Requirements
All switches, slow-blow fuses and power cables are customer supplied and must be chosen as outlined by
applicable national or local codes. Installation must be performed by qualified personnel. Use a separate
primary line disconnect switch for the power supply. If slow-blow fuses are not available or not allowed by
applicable codes, use a motor-start circuit breaker.
* Note: Use the smaller diameter 4/0 AWG cable (1.6" / 40.6 mm) rated for 90° C (194° F) rather than an equivalent
larger diameter cable (350 MCM, 2.05" / 52 mm) rated for 60° C (140° F) to accommodate the bend radius neces-
sary to connect incoming power cable to the power supply.
Line Disconnect Switch
The line disconnect switch serves as the supply voltage disconnecting (isolating) device. Install this switch on a
wall near the power supply for easy accessibility by the operator. The line disconnect switch must be installed
by qualified personnel following all applicable national or local codes. The switch should:
• isolate the electrical equipment and disconnect all live conductors from the supply voltage when in the "OFF
position
• have one "OFF" and one "ON" position clearly marked with "0" (OFF) and "1" (ON)
• have an external operating handle capable of being locked in the "OFF" position
• contain a power operated mechanism that serves as an emergency stop
• have slow-blow fuses installed for the proper breaking capacity (see table above)
Power Cable
Wire sizes vary based on the distance of the receptacle from the main box. The suggested wire sizes listed in the
table above were taken from the U.S. National Electric Code 1990 handbook, table 310.16. Use a 4-conductor (3
conductor with ground) input power cable with a conductor temperature rating of 60° C (140° F) or 90° C (194° F).
The cable should be installed only by a licensed electrician following national or local codes.