Hobart H-9B Gun, Owner'S Manual

Page: 16 / 52

OM-947 Page 12
4-2. Duty Cycle And Overheating
duty1 4/95 − 210 517-B
Duty Cycle is percentage of 10 min-
utes that unit can weld at rated load
without overheating.
If unit overheats, thermostat(s)
opens, output stops, and cooling
fan runs. Wait fifteen minutes for
unit to cool. Reduce amperage or
duty cycle before welding.
NOTICE − Exceeding duty cycle
can damage unit or gun and void
warranty.
Overheating
0
15
A or V
OR
Reduce Duty Cycle
Minutes
20% duty cycle at 85 amps
2 Minutes Welding 8 Minutes Resting
Output Amperes
Duty Cycle %
1
4 10
20
40 60 100 2 6 80 8
10
20
40
60
80
100
200
135
4-3. Volt-Ampere Curves
The volt-ampere curves show the
minimum and maximum voltage
and amperage output capabilities of
the welding power source. Curves
of other settings fall between the
curves shown.
ssb1.1 10/91 − 210 518-B
8
10
12
14
16
18
20
22
24
26
28
0 10 20 30 40 50 60 70 80 90 100 110 120 130
Voltage
Amperage
Range 1
Range 2
Range 3
Range 4