Miller STi 270, Owner'S Manual

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OM-263 706 Page 10
4-3. Weld Output Terminals And Selecting Cable Sizes*
NOTICE − The Total Cable Length in Weld Circuit (see table below) is the combined length of both weld cables. For example, if the power source is
30 m (100 ft) from the workpiece, the total cable length in the weld circuit is 60 m (2 cables x 30 m). Use the 60 m (200 ft) column to determine cable
size.
!
Turn off power be-
fore connecting to
weld output termi-
nals.
!
Do not use worn,
damaged, under-
sized, or repaired
cables.
Weld Output
Terminals
Weld Cable Size** and Total Cable (Copper) Length in Weld Circuit
Not Exceeding***
30 m (100 ft) or Less
45 m
(150 ft)
60 m
(200 ft)
70 m
(250 ft)
90 m
(300 ft)
105 m
(350 ft)
120 m
(400 ft)
Welding
Amperes
10 − 60%
Duty
Cycle
mm
2
(AWG)
60 − 100%
Duty
Cycle
mm
2
(AWG)
10 − 100% Duty Cycle
mm
2
(AWG)
100 20 (4) 20 (4) 20 (4) 30 (3) 35 (2) 50 (1) 60 (1/0) 60 (1/0)
150 30 (3) 30 (3) 35 (2) 50 (1) 60 (1/0) 70 (2/0) 95 (3/0) 95 (3/0)
200 30 (3) 35 (2) 50 (1) 60 (1/0) 70 (2/0) 95 (3/0) 120 (4/0) 120 (4/0)
*
This chart is a general guideline and may not suit all applications. If cable overheats, use next size larger cable.
**Weld cable size is based on either a 4 volts or less drop or a current density of at least 300 circular mils per ampere.
***For distances longer than those shown in this guide, call a factory applications representative.
Milan Ref. S-0007-K 2013−10
4-4. TIG Lift-Arc DCEN (Direct Current Electrode Negative) Connections
!
Turn off power before mak-
ing connections.
1 Positive (+) Weld Output
Terminal
Connect work lead to positive weld
output terminal.
2 Negative (−) Weld Output
Terminal
Connect TIG torch to negative weld
output terminal.
3 Gas Cylinder
4 Cylinder Valve
Open valve slightly so gas flow
blows dirt from valve. Close valve.
5 Regulator/Flowmeter
6 Flow Adjust
Typical flow rate is 15 cubic feet per
hour (7.1 liters per minute).
Connect torch gas hose to regula-
tor/flowmeter.
7 Gas Valve
Valve controls gas preflow and
postflow. Open valve on torch just
before welding.
Tools Needed:
21 mm (11/16, 1-1/8 in.)
3
4
5
6
7
1
2