Tweco Hefty II CC CV Voltage Sensing Wire feeder - Manual (Page 20)

25. GUN CLAMP KNOB - Tighten this knob to
secure the welding gun to the wire feeder.
26. OUTPUT WIRE GUIDE - This guide is re-
quired to direct the welding wire from the drive feed
roll to the welding gun cable.
Power Source Compatibility:
Since the HEFTY II STAINLESS operates on arc
voltage, it will work with most constant current (CC)
or constant voltage (CV) DC-type power sources.
When connected to a HEFTY II STAINLESS, the
maximum allowed open circuit voltage (OCV) of the
power source is 100 VDC. Open circuit voltages
exceeding 100 VDC will damage or shorten the life
of the unit.
NOTE: Because of the high open circuit
voltage associated with most CC power
sources, it is recommended to place the
HEFTY
11
STAINLESS power switch in the
OFF position when not welding. This pro-
cedure will prolong the life of electrical com-
ponents connected to the power input lines.
When using the HEFTY II STAINLESS, there
must be at least 15 VDC between the output termi-
nals of the power source during standby and while
welding. Otherwise, the unit will not have enough
input voltage to operate properly.
A contactor is a standard component of the
HEFTY II STAINLESS and allows the welding wire
to remain electrically “cold” until the gun switch
trigger is depressed. This contactor is rated for 330
amps of welding current at a 60% duty cycle. If the
weld current or duty cycle rating is exceeded, the
contactor will be damaged or its life shortened.
Figure 3-5 Feedhead Assembly
430429-456
DESCRIPTION OF EQUIPMENT
June 5, 2000 Revised 3-7