PlasmaCuttingBuyer’sGuide

PlasmaCuttingBuyer’sGuide

1

Table Of Contents

Page

What Is Air Plasma? 2

Where Can I Use My Plasma Cutter? 2

Plasma — A Cut Above Oxyfuel 3

What To Look For In A Plasma Cutter 4

Operating A Plasma Arc For Cutting 9

Spectrum® Series Air Plasma

Cutting Systems 10

Accessories 12

Spectrum® Product Specifications 15

Cutting Guide 16

January 2004

2

Your Personal Guide ToPlasma Cutters

The air plasma arc process provides good qualitycutting at very high speeds for a much lower cost thanother cutting methods. Plasma arc also offers qualitygouging and piercing capabilities. Miller Electric Mfg. Co., aleading worldwide manufacturer of welding and cuttingpower sources, has designed this handy reference guide to assist you in making an informedbuying decision.

What Is Air Plasma?Plasma arc cutting is a process where an open arc,

much like in TIG welding, can be constricted by passingthrough a small nozzle, or orifice, from the electrode tothe workpiece. The gas used, typically air, combines withan electrical current to create a high temperature plasmaarc. When placed in contact with an electricallyconductive material, the arc passes through the metal,melting a thin area. The force of the arc pushes the moltenmetal through the workpiece and severs the material.

Where Can I Use My Plasma Cutter?

Since the plasma process is capable of cuttingmetals ranging from thin gauge aluminum to 1-1/2 instainless and carbon steel, it can be used in manyapplications, includingstack cutting, beveling,shape cutting, gouging,and piercing. Theseprocesses are used insuch industries as metalfabrication,construction, mainte-nance, automotiverepair, and metal art andsculpting.

3

Plasma — A Cut Above Oxyfuel

While oxyfuel has been the most common method ofcutting carbon steel in the past, plasma cutting providesnumerous advantages over oxyfuel. It cuts faster; doesnot require a pre-heat cycle; produces a small and moreprecise kerf width (the width of the cut); and has a smallerheat-affected zone, which prevents the surrounding areafrom warping or damaging paint.

In addition, the plasma process cuts any type ofelectrically conductive metal (the oxyfuel process cannotcut stainless steel or aluminum). Plasma cutting is acleaner, less expensive and more convenient method ofmetal cutting because clean, dry air is used for mostplasma cutting applications.

4

What To Look For In A Plasma Cutter

When purchasing a plasma cutting unit there areseveral features to consider before making your buyingdecision. However, the performance of the machine andits ease-of-use greatly outweigh any other factors.

A. True Blue® Warranty. For highly engineeredplasma products, youneed a manufacturerwho will stand behindthem. Miller backs all ofits power sources with the most comprehensive coveragein the industry. The Spectrum Series has a three-yearwarranty on the power source, parts and labor. Originalrectifier parts have a five-year warranty and the ICEtorches supplied with each Spectrum have a one-yearparts and labor warranty.

B. Input Power. When selecting a plasma cutter, it isimportant to note the input power available where theplasma cutting is going to take place. For an on-sitesolution, the Spectrum 2050 cuts up to 5/8 in. steel whenpowered by any Miller generator providing 8,000 watts ormore generator power.

Miller also makes hooking up your plasma cuttereasy with two innovative input power technologies:

5

Auto-Line™, featured exclusively in the Spectrum 2050,allows direct connection to ANY primary power level: 50 or 60 Hz, single- or three-phase, 208 through 575 VAC.Simply connect the power cord to the correct plug orjunction box and start cutting. Auto-Line™ lets youplasma cut at any location, on any job site and in anycountry without worrying about opening and manuallylinking the machine or damaging the machine fromincorrect hookup.

Auto-Line™

Auto-Link® is featured in the Spectrum 3080. With thistechnology, the machine’s circuitry senses the typeof incoming power (208 V, 230 V or 460 V) and auto-matically configures (or “links”) to provide the correctoutput voltage. This is unlike many competitive systems,which can only operate at a single voltage level or requirethe operator to remove the cover of the machine andmanually link wires to switch between voltages.

Auto-Link®

Pri

mary

Input

Volt

age

Auto

-Lin

k®�

Auto-Link automatically links to primary voltage being used. (208 V, 230 V or 460 V, single- or three-phase)

Output Voltage

Auto-

Line™

Handles line power fluctuations from 190 to 630 VAC during operation without losing capacity. (Single- or three-phase, 50 or 60 Hz)

Pri

mary

Input

Volt

age

ConsistentOutput Voltage

6

C. Cutting Capability and Speed. Determine thetype and thickness of metal you are cutting and yourdesired cutting speed. Then compare your needs to thecutting capacity and cutting speed of the machine you areconsidering. While there is no standard for cuttingspeeds in the industry, Miller qualifies its cuts by threestandards:

The output power needed from a plasma cuttingmachine depends primarily on the thickness and type ofmaterial you need to cut. Cutting speed makes asignificant difference in production time and operatorcomfort. For example, Miller’s Spectrum® 375 provides 27amps of output power and cuts metal up to 3/8 in. thickat approximately 8 inches per minute while drag cutting.If a more powerful machine is necessary, the Spectrum1250 provides 100 amps of cutting output and can cutmetal up to 1-1/2 in. thick at approximately 8 inches perminute.

Rated Cutting Capacity10 inches per minute (minimum speed at which an operator

achieves a smooth, steady cut using a hand-held torch).

Maximum Quality Cutting CapacityGood-quality cut achieved at lower speeds.

Sever Cut CapacityMaximum cut achieved in ideal conditions.

7

D. Air Requirement. All Miller air plasma cuttingmachines require a clean, dry air supply. Check therequired PSI needed for each machine. A filter and dryerare recommended for all applications (see page 14).

The Spectrum 125C (see page 10) comes completewith a built-in piston-driven compressor which providesthe exact amount of air needed for cutting. No externalair hook-up is needed.

E. Durable Torch. While the type of torch depends onthe application, it is always best to purchase a heavy-dutytorch. With each Spectrum unit, Miller supplies a ruggedICE torch with an epoxy cup that outlives typical ceramicparts and is virtually unbreakable. There are two differenttypes of torches available: hand-held or machine-held.Miller’s machine-held torches are designed with a 1-3/8in. diameter fitting that is perfect for an automation orclamp-type setup.

The Miller ICE torch also provides a drag shield thatattaches to the cup and holds the tip 1/16 to 1/8 in. off ofthe workpiece. This permits the operator to drag the torchon the workpiece while cutting at full output, whichincreases operator comfort and makes template cuttingeasier. Drag shields work with the flow dynamics of thetorch to provide better cooling of the consumable parts forlonger parts life.

F. High-Frequency Starts. High frequency (HF)can interfere with controls or computers, so look for aplasma cutting unit that starts without high frequency ifthe plasma cutter is placed near equipment withcomputer controls. To avoid this problem, Miller provides contact start without high frequency in most of itstorches. (Exception Spectrum 1250 only one with HF.)

G. Postflow Cooling Circuit. To extend the life ofconsumables and reduce the cost of replacing them, thepostflow circuit cools the consumables and torch withpostflow air after you release the trigger. Miller units areavailable with postflow cooling circuits.

8

H. User-friendly Front Panel. Look for a machinewith easy-to-use and easy-to-understand controls,including troubleshooting diagnostic lights. In addition,some machines provide a built-in consumable compartment conveniently mounted on the front panelto make consumables readily available for replacingwhile cutting.

I. Portability. Weight and size are important if there isa need for portability. There are many hand-portableunits available that weigh less than 75 lb., including theSpectrum 125C, the Spectrum 375, the Spectrum 625, theSpectrum 2050, and the Spectrum 3080. Miller also offerscompatible running gears for some larger, heaviermachines.

J. Built-in Gas/Air Filter/Regulator. A regulatorpositioned on the outside of the unit is vulnerable todamage during transportation, but the Spectrum Series’regulators are protected inside the power sources. TheSpectrum Series also has a standard air connection on theback panel for easy gas or air hook-up.

ON

OFFPRESSURE 60 PSI

24

27

20

16

2

1

4

5

3

1. Status and Troubleshooting Lights2. Power Switch3. Output Control4. Gas/Air Pressure Gauge5. Gas/Air Pressure Adjustment Control

9

Operating A Plasma Arc For Cutting

Begin cutting by placing the torch as close as possible to the edge of the base metal. Pull the trigger toinitiate the preflow air; the pilot arc will then light, followed by the cutting arc. Wait for the arc to penetratethrough the bottom of the workpiece. Start moving thetorch slowly forward, perpendicular to the workpiece.Watch sparks leaving the bottom of the workpiece tojudge speed. If the sparks are not visible at the bottom ofthe plate, you have not penetrated the metal. This isbecause your travel speed is too fast or you haveinsufficient output amperage.

At the end of a cut, angle the torch slightly or pausebriefly to completely finish the cut. If the system provides apostflow circuit, the postflow air will continue for a short period of time after the trigger isreleased to cool the torch and consumable parts,however, cutting can be resumed immediately.

To maximize cutting speeds, it is recommended toturn your power source to full output for all materialthicknesses.

Proper Safety ProceduresSafety procedures must be closely followed in any

application of the plasma cutting machine. Be aware ofpotential hazards involved with the process including, highvoltages, noise, temperatures, flammable materials, fumes,ultraviolet radiation and molten metal. Proper weldingclothing should be worn, as well as shaded eyeprotection, as specified by the manufacturer. As with allindustrial products, read the owner’s manual for propersafety procedures.

10

Spectrum® Series Air PlasmaCutting Systems

When you need rugged cutting systems, look to theSpectrum Series, which is ideal for cutting mild steel,stainless steel and aluminum from gauge thickness to 1-1/4 in. Portable and industrial models are available to fitthe demands of your cutting application. In addition, manyof the Miller Spectrum products provide air plasma arcgouging and excellent piercing capabilities.

Spectrum® 125CThe Spectrum 125C boasts a

built-in piston-driven air compressorgiving it an “out of the box, ready to cut”attitude. This economical unit is capable of a maximum cut up to 3/16 in. steel and a rated cut at 1/8 in.At about 50 lb. (weight with torch), itsportability makes it an appealing option forHVAC, sheet metal applications, auto body repair,and the home hobbyist.

Spectrum® 375The Spectrum 375 is an

economical plasma cutting system for work on all conductive metals includingmild steel rated at 3/8 in (9.5 mm),aluminum to 1/4 in (6.4 mm), andstainless steel to 5/16 in (8 mm) whiledrag cutting. Stand-off cutting allows youto cut 1/2 in (13 mm) mild steel. Solid-state design and Miller’s reliable technologypacks a lot of performance into a very portable, 56.5 lb(weight with torch) package. This versatile power sourceadapts to your shop or work site by operating from either115 or 230 volt AC power. The 375 is ideal for maintenance,light construction, prototyping, body shops, fabrication and HVAC ductwork.

Spectrum® 625The Spectrum 625 is a dependable

plasma cutting system for applications frommaintenance to construction. The Spectrum625 provides a ½" rated cut on mild steel andup to 3/8" on aluminum. It is equipped withtwo exclusive Miller features: Wind TunnelTechnology™which prevents abrasive

11

dust and particles from damaging internal components andFan-on-Demand™, a cooling systems that only operateswhen needed. It can also be powered by any Millergenerator with generator power output of 8 kW or moreproviding up to a 5/8" cut. The Spectrum 625 packs a lot ofperformance into a portable, 60lb (weight with torch) unitto handle your plasma cutting needs.

Spectrum® 2050The Spectrum 2050 is a

portable cutting and gouging systemwith Auto-Line™,a Miller feature thataccepts any type of input power from208 to 575 VAC. It can also be powered by any Millerwelding generator with generatorpower output of 8 KW or more—such as the Bobcat™225 NT, and theTrailblazer® 301 G (as well as equivalentcompetitive equipment). The Spectrum 2050 weighs 86 lb.(weight with torch), provides a cutting range of 20 to 55 amps and makes a 7/8 in rated cut on mild steel. It isequipped with two exclusive Miller features: Wind TunnelTechnology™ which prevents abrasive dust and particlesfrom damaging internal components, and Fan-on-Demand™,a cooling system that only operates when needed. Bothfeatures increase productivity and energy efficiency, butmore importantly decrease service required formaintenance.

Spectrum® 3080The portable 92 lb. (weight with

torch) Spectrum 3080 is equippedwith Auto-Link®, a Miller technologythat senses the type of incomingpower (208 V, 230 V or 460 V) andprovides correct output voltageautomatically. The Spectrum 3080,featuring Wind Tunnel Technology™

and Fan-on-Demand™, provides 80amps of power to perform at rated cut on mild steeland 7/8 in on stainless steel and aluminum. Providingoptimum peak power, the Spectrum 3080 power sourcegives high quality cutting performance and excellentgouging characteristics.

12

Spectrum® 1250Miller’s highest powered plasma

cutter, the Spectrum 1250, is a heavy-dutyindustrial air plasma cutting and gougingsystem. It also operates on three-phasepower at 80 percent duty cycle and has arated cutting capacity of 1-1/4 in. on mildor stainless steel and 1 in. on aluminum.

Cutting Guide Suction/Magnetic Base with Extension ArmAdd this to your Cutting Guide for a convenientattachment to all flat surfaces. The extended armaccommodates holes up to 30 inches in diameter.

Part #195 979

Accessories

Circle Cutting Guides Cuts straight lines or circles up to 12 inches in diameter with ease. Fits all Miller ICE torches.

Part #195 981

13

Standoff Roller GuideHelps maintainrecommended standoffdistance when usingextended consumables.

Part #194 883

Plastic Consumables BoxCompartments for storing additional parts and accessories.

Part #127 493

#30 A Economy Running Gear and Cord WrapEconomical running gear with angle for easy frontpanel access provides storage for gloves and tools.(Fits Spectrum® 125C, 375, 2050 and 3080).

#30 Economy Running GearPart #195 093

14

Protective CoversHeavy-duty, water resistantmaterial, and mildew-resistant.Protects and maintains thefinish of the welder.

#195 144 For Spectrum 125C and 375.

#195 145 For Spectrum 625.

#195 271 For Spectrum 2050.

#195 144cover shown

Plasma Torch Consumable Kits#211 166 For ICE-12#206 635 For ICE-27#207 187 For ICE-40#206 636 For ICE-55#211 173 For ICE-80

Motor Guard Air FilterFor Spectrum 375, 625, 2050 and3080. This filter is equipped with amounting bracket that allowsinstallation on the top, side, or rearpanel of most plasma cutters. Thefilter is equipped with 1/4 in NPTport to match the fittings on mostplasma systems; it has a ratedairflow of over 45 SCFM.

Part #042 306

RTI FilterFor Spectrum 375, 625, 2050, 3080and 1250. Dryer will remove water,dirt and oil as small as one micronwith 99.9% efficiency. Can bemounted on plasma cutter or onwall. Install as close as possible topoint of air consumption.

Part #195 188

15

Spect

rum

®P

roduct

Speci

fica

tions

Rate

d O

utp

ut

12 a

mps

at

110

volts

DC

27 a

mps

at 9

0 v

olts

DC

,35%

duty

cyc

le

40 a

mps

at 1

40 v

olts

DC

,50%

duty

cyc

le

55 a

mps

at 1

40 v

olts

DC

,60%

duty

cyc

le f

or

3-p

has

e,50%

duty

cyc

le f

or

1-p

has

e

80 a

mps

at 1

40 v

olts

DC

, 60%

duty

cyc

le f

or

3-p

has

e,40%

duty

cyc

le f

or

1-p

has

e

100 a

mps

at 1

20 v

olts

DC

, 80%

duty

cyc

le

Pla

sma

Cutt

ing P

roduct

Spect

rum

®

125C

Spect

rum

®

375

Spect

rum

®

625

Spect

rum

®

2050

Spect

rum

®

3080

Spect

rum

®

1250

Input

Pow

er

120 V

, 1-p

has

e, 6

0 H

z

115 o

r 230 V

AC

, 1-p

has

e,

60 H

z

208/2

30 V

AC

, 1-p

has

e,

50/6

0 H

z

Auto

-Lin

e ac

cepts

input

voltag

e fr

om

208 t

o 5

75 V

AC

, 1-

and

3-p

has

e ca

pac

itie

s, 5

0/6

0 H

z

Auto

-Lin

k 230 o

r 460 1

- an

d

3-p

has

e ca

pac

itie

s, 5

0/6

0 H

z

200/

230/

460

or 2

30/4

60/5

75 V

AC

,220/3

80/4

15 V

AC

, 3-p

has

e,

50/6

0 H

z

Mil

d S

teel

1/8

in.

3/8

in.

1/2

in.

7/8

in.

1 in

.

1-1/

4 in

.

Sta

inle

ss S

teel

1/16

in.

1/4

in.

3/8

in.

3/4

in.

7/8

in.

1 in

.

Alu

min

um

1/16

in.

1/4

in.

3/8

in.

3/4

in.

7/8

in.

1 in

.

Reco

mm

ended

Genera

tor

Pow

er

2500 w

atts

4000 w

atts

8500 w

atts

11,0

00 w

atts

17,0

00 w

atts

NR

Pro

duct

W

eig

ht

50 lb.

(22.7

kg)

56.5

lb.

(25.6

kg)

60 lb.

(27.2

kg)

86 lb.

(39.0

kg)

92 lb.

(41.7

kg)

410 lb.

(186 k

g)

Rate

d C

utt

ing T

hic

kness

es

16

For detailed literature, a full-line catalog or to locate your nearest distributor,

call 1-800-4-A-MILLER (1-800-426-4553)

Cutt

ing G

uid

e S

pect

rum

Cutt

ing o

n E

ngin

e D

rive

n W

eld

ers

Engin

e D

rive

n W

eld

ers

Legend N

T

Bob

cat®

225

NT

PR

E 10

/03

Bob

cat®

225

NT

PO

ST

10/0

3

Tra

ilbla

zer®

280 N

T

Bobca

t®250 N

T

Tra

ilbla

zer®

301 G

Tra

ilbla

zer®

DC

Tra

ilbla

zer®

Pro

350

Pip

eP

ro™

CC

/CV

Big

40

®C

AT C

C/C

V

Big

Blu

e®

402 C

C/C

V

Ste

el

Quali

ty C

ut

3/8"

3/8”

3/8”

3/8"

3/8"

3/8"

3/8"

3/8"

3/8"

3/8"

3/8"

Spect

rum

Outp

ut

Am

p S

ett

ing

27 A

(24

0 V

, ful

l KV

A p

lug)

27 A

(24

0 V

, ful

l KV

A p

lug)

27 A

(24

0 V

, ful

l KV

A p

lug)

27 A

(24

0 V

, ful

l KV

A p

lug)

27 A

(24

0 V

, ful

l KV

A p

lug)

27 A

(24

0 V

, ful

l KV

A p

lug)

27 A

(24

0 V

, ful

l KV

A p

lug)

27 A

(24

0 V

, ful

l KV

A p

lug)

27 A

(24

0 V

, ful

l KV

A p

lug)

27 A

(24

0 V

, ful

l KV

A p

lug)

27 A

(24

0 V

, ful

l KV

A p

lug)

Spect

rum

Outp

ut

Am

p S

ett

ing

35A

45 A

45 A

45 A

50A

50 A

50 A

50 A

55 A

55 A

55 A

*M

odel

s m

anufa

cture

d a

fter

(an

d incl

udin

g)

seri

al n

um

ber

KJ2

83702.

Note

: LP

pow

ered

mac

hin

es n

eed t

o b

e der

ated

15%

.

375

2050*/2

050 (

55A

)

Genera

tor

Pow

er

5 kW

8 kW

8 kW

10 k

W

10 k

W

10 k

W

12 k

W

12 k

W

15 k

W

20 k

W

Ste

el

Quali

ty C

ut

1/2

”

5/8"

5/8"

5/8"

3/4"

3/4"

3/4"

3/4"

3/4"

3/4"

5/8"

Spect

rum

Outp

ut

Am

p S

ett

ing

30 A

(240V

)

40 A

(240V

)

40 A

(240V

)

40 A

(240V

)

40 A

(240V

)

40 A

(240V

)

40 A

(240V

)

40 A

(240V

)

40 A

(240V

)

40 A

(240V

)

40 A

(240V

)

625

Ste

el

Quali

ty C

ut

3/8"

5/8"

5/8"

5/8"

5/8"

5/8"

5/8"

5/8"

5/8"

5/8"

5/8"

while

not

wel

din

g

10,0

00 w

atts

9,0

00 c

ontinuous

An Illinois Tool Works Company©2003 Miller Electric Mfg Co.

www.Mi l lerWelds.com

For detailed specification sheets or to locate your nearest Miller distributor, call:

1-800-4-A-Miller(1-800-426-4553)