Owner`s manual

ManualsBrandsMiller ManualsIndustrialSTi 270C

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

(AWG)

60 − 100%

Duty

Cycle

(AWG)

10 − 100% Duty Cycle

(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.)