January 1991 FORM: OM-534
Effective With Style No. JG-24
MODEL: SECONDARY
CONTACTOR
OWNER’S MANUAL
MILLER ELECTRIC Mfg. Co.
A Miller Group Ltd., Company
P.O. Box 1079
Appleton, WI 54912 USA
Tel. 414-734-9821
IMPORTANT: Read and understand the entire contents of both this manual
and the power source manual used with this unit, with special emphasis on
the safety material throughout both manuals, before installing, operating, or
maintaining this equipment. This unit and these instructions are for use only
by persons trained and experienced in the safe operation of welding equip-
ment. Do not allow untrained persons to install, operate, or maintain this unit.
Contact your distributor if you do not fully understand these instructions.
SB-110 488-A PRINTED IN U.S.A.
LIMITED WARRANTY − Subject to the terms and conditions
hereof, Miller Electric Mfg. Co., Appleton, Wisconsin warrants to
its Distributor/Dealer that all new and unused Equipment fur-
nished by Miller is free from defect in workmanship and material
as of the time and place of delivery by Miller. No warranty is made
by Miller with respect to engines, trade accessories or other
items manufactured by others. Such engines, trade accessories
and other items are sold subject to the warranties of their respec-
tive manufacturers, if any. All engines are warranted by their
manufacturer for one year from date of original purchase, except
Tecumseh and Onan engines which have a two year warranty.
Except as specified below, Miller’s warranty does not apply to
components having normal useful life of less than one (1) year,
such as spot welder tips, relay and contactor points, MILLER-
MATIC parts that come in contact with the welding wire including
nozzles and nozzle insulators where failure does not result from
defect in workmanship or material.
Miller shall be required to honor warranty claims on warranted
Equipment in the event of failure resulting from a defect within the
following periods from the date of delivery of Equipment to the
original user:
1. Arc welders, power sources, robots, and 1 year. . . . . . . .
components
2. Load banks 1 year. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3. Original main power rectifiers 3 years. . . . . . . . . . . . . . . . .
(labor − 1 year only)
4. All welding guns, feeder/guns and torches 90 days. . . . . .
5. All other Millermatic Feeders 1 year. . . . . . . . . . . . . . . . . . .
6. Replacement or repair parts, exclusive of labor 60 days. .
7. Batteries 6 months. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
provided that Miller is notified in writing within thirty (30) days of
the date of such failure.
As a matter of general policy only, Miller may honor claims sub-
mitted by the original user within the foregoing periods.
In the case of Miller’s breach of warranty or any other duty with
respect to the quality of any goods, the exclusive remedies
therefore shall be, at Miller’s option (1) repair or (2) replacement
or, where authorized in writing by Miller in appropriate cases, (3)
the reasonable cost of repair or replacement at an authorized
Miller service station or (4) payment of or credit for the purchase
price (less reasonable depreciation based upon actual use)
upon return of the goods at Customer’s risk and expense.
MILLER’s option of repair or replacement will be F.O.B., Factory
at Appleton, Wisconsin, or F.O.B. at a MILLER authorized serv-
ice facility, therefore, no compensation for transportation costs
of any kind will be allowed. Upon receipt of notice of apparent de-
fect or failure, Miller shall instruct the claimant on the warranty
claim procedures to be followed.
ANY EXPRESS WARRANTY NOT PROVIDED HEREIN
AND ANY IMPLIED WARRANTY, GUARANTY OR REPRE-
SENTATION AS TO PERFORMANCE, AND ANY REMEDY
FOR BREACH OF CONTRACT WHICH, BUT FOR THIS PRO-
VISION, MIGHT ARISE BY IMPLICATION, OPERATION OF
LAW, CUSTOM OF TRADE OR COURSE OF DEALING, IN-
CLUDING ANY IMPLIED WARRANTY OF MERCHAN-
TABILITY OR OF FITNESS FOR PARTICULAR PURPOSE,
WITH RESPECT TO ANY AND ALL EQUIPMENT FUR-
NISHED BY MILLER IS EXCLUDED AND DISCLAIMED BY
MILLER.
EXCEPT AS EXPRESSLY PROVIDED BY MILLER IN WRIT-
ING, MILLER PRODUCTS ARE INTENDED FOR ULTIMATE
PURCHASE BY COMMERCIAL/INDUSTRIAL USERS AND
FOR OPERATION BY PERSONS TRAINED AND EXPERI-
ENCED IN THE USE AND MAINTENANCE OF WELDING
EQUIPMENT AND NOT FOR CONSUMERS OR CONSUMER
USE. MILLER’S WARRANTIES DO NOT EXTEND TO, AND
NO RESELLER IS AUTHORIZED TO EXTEND MILLER’S
WARRANTIES TO, ANY CONSUMER.
LIMITED WARRANTY
EFFECTIVE: MARCH 15, 1989
This warranty supersedes all previous MILLER warranties and is exclusive with no other guarantees or warranties expressed or implied.
OM-543 − 1/91
Before unpacking equipment, check carton for any
damage that may have occurred during shipment. File
any claims for loss or damage with the delivering car-
rier. Assistance for filing or settling claims may be ob-
tained from the distributor and/or the equipment manu-
facturer’s Transportation Department.
When requesting information about this equipment, al-
ways provide the Model Description and Serial or Style
Number.
Use the following spaces to record the Model Designa-
tion and Serial or Style Number of your unit. The infor-
mation is located on the data card or the nameplate.
Model
Serial or Style No.
Date of Purchase
RECEIVING-HANDLING
TABLE OF CONTENTS
Section No. Page No.
SECTION 1 − SAFETY PRECAUTIONS AND SIGNAL WORDS
1-1. General Information And Safety 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-2. Safety Alert Symbol And Signal Words 1. . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 2 − SPECIFICATIONS
2-1. Description 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 3 − INSTALLATION
3-1. Location 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-2. Installation 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-3. Trigger Hold Connections For DC Shielded Metal Arc Welding (SMAW) . .
2
3-4. Weld Output Connections For DC Shielded Metal Arc Welding (SMAW) . .
2
3-5. Weld Output Connections For Gas Metal Arc Welding (GMAW) 3. . . .
3-6. Weld Output Connections For AC Shielded Metal Arc Welding (SMAW) . .
4
3-7. Trigger Connections 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-8. Input Power Connections 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 4 − SEQUENCE OF OPERATION
4-1. Shielded Metal Arc Welding (SMAW) 7. . . . . . . . . . . . . . . . . . . . . . . . . . .
4-2. Gas Metal Arc Welding (GMAW) 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 5 − MAINTENANCE & TROUBLESHOOTING
5-1. Inspection And Upkeep 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5-2. Overload Protection 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5-3. Troubleshooting 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 6 − ELECTRICAL DIAGRAM
Diagram 6-1. Circuit Diagram 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 7 − PARTS LIST
Figure 7-1. Complete Assembly 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
LIST OF CHARTS AND TABLES
Table 2-1. Specification 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 5-1. Troubleshooting 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
OM-534 Page 1
SECTION 1 − SAFETY PRECAUTIONS AND SIGNAL WORDS
1-1. GENERAL INFORMATION AND SAFETY
A. General
Information presented in this manual and on various la-
bels, tags, and plates on the unit pertains to equipment
design, installation, operation, maintenance, and
troubleshooting which should be read, understood, and
followed for the safe and effective use of this equipment.
The nameplate of this unit uses international symbols
for labeling the front panel controls. The symbols also
appear at the appropriate section in the text.
B. Safety
The installation, operation, maintenance, and trouble-
shooting of arc welding equipment requires practices
and procedures which ensure personal safety and the
safety of others. Therefore, this equipment is to be in-
stalled, operated, and maintained only by qualified per-
sons in accordance with this manual and all applicable
codes such as, but not limited to, those listed at the end
of Section 1 − Safety Rules For Operation Of Arc Weld-
ing Power Source in the welding power source Owner’s
Manual.
1-2. SAFETY ALERT SYMBOL AND SIGNAL
WORDS
The following safety alert symbol and signal words are
used throughout this manual to call attention to and
identify different levels of hazard and special instruc-
tions.
This safety alert symbol is used with the signal
words WARNING and CAUTION to call atten-
tion to the safety statements.
WARNING statements identify procedures or
practices which must be followed to avoid seri-
ous personal injury or loss of life.
CAUTION statements identify procedures or
practices which must be followed to avoid minor
personal injury or damage to this equipment.
IMPORTANT statements identify special instructions
necessary for the most efficient operation of this equip-
ment.
SECTION 2 − SPECIFICATIONS
Table 2-1. Specification
Rating
250 Amperes @
60% Duty Cycle
Input
115 VAC 50-100 Hz
12 VDC
Net
14 lb.
(6.3 kg)
Ship
17 lb.
(7.7 kg)
SB-110 488-A
A
B
C
D
E
F
A
B
B
B
A 1 in. (25 mm)
2 in. (51 mm)
1/2 in. (13 mm)
11-1/2 in. (453 mm)
3-5/8 in. (143 mm)
11-1/4 in. (443 mm)
B
C
D
E
F
Figure 2-1. Dimensions
OM-534 Page 2
2-1. DESCRIPTION
This unit is a secondary contactor that provides electri-
cal isolation between the electrode and welding power
source output. Weld output is available when the opera-
tor closes the secondary contactor by means of a trigger
switch. This unit can operate on 115VAC or 12VDC input
power. The unit is shipped prepared for DC SMAW
applications.
SECTION 3 − INSTALLATION
3-1. LOCATION (Figures 2-1 and 3-1)
The location should allow room around the unit for mak-
ing necessary connections and for maintenance and re-
pair functions. The service life and efficiency of this unit
are reduced when subjected to high levels of dust, dirt,
moisture, corrosive vapors, and extreme heat.
Mounting holes are provided. Figure 2-1 gives overall di-
mensions and mounting hole layout. Figure 3-1 gives lo-
cation layout.
3-2. INSTALLATION
The Secondary Contactor can be installed on top of the
welding power source.
WARNING: ELECTRIC SHOCK can kill.
• Do not touch live electrical parts.
• Shut down welding power source, and dis-
connect input power employing lockout/tag-
ging procedures before installing and con-
necting unit.
Lockout/tagging procedures consist of pad-
locking line disconnect switch in open position,
removing fuses from fuse box, or shutting off
and red-tagging circuit breaker or other discon-
necting device.
1. Remove screws from front of welding power
source cover.
2. Place unit on cover. Mounting bracket holes
should line up with at least two holes in cover.
3. Secure unit to cover using screws removed in
Step 1.
SA-110 489-A
Figure 3-1. Mounting Location
3-3. TRIGGER HOLD CONNECTIONS FOR DC
SHIELDED METAL ARC WELDING (SMAW)
Trigger hold allows the operator to release the trigger
switch after an arc is established when performing DC
Shielded Metal Arc Welding (SMAW). The unit is
shipped with internal trigger hold connections made. For
trigger hold to function, the electrode weld output cable
needs to be routed through the reed relay inside the unit
(for weld output connections see Section 3-4).
If trigger hold is not desired (operator holds trigger
switch closed while welding) the jumper link connecting
terminals H and J on terminal strip 1T must be removed
(see Section 3-4).
3-4. WELD OUTPUT CONNECTIONS FOR DC
SHIELDED METAL ARC WELDING (SMAW)
WARNING: ELECTRIC SHOCK can kill.
• Do not touch live electrical parts.
• Shut down welding power source, and dis-
connect input power employing lockout/tag-
ging procedures before installing and con-
necting unit.
Lockout/tagging procedures consist of pad-
locking line disconnect switch in open position,
removing fuses from fuse box, or shutting off
and red-tagging circuit breaker or other discon-
necting device.
OM-534 Page 3
CAUTION: INCORRECT POLARITY will
damage contactor.
• Magnetic blowout feature requires positive
polarity at positive contactor terminal.
IMPORTANT: Refer to the welding power source Own-
er’s Manual for proper cable information, connection
points, and necessary associated information. Obtain or
make proper length weld cables for this installation.
A. DC Electrode Positive Connections
1. Remove wrapper from unit.
2. If trigger hold is desired be sure jumper link is in
place between terminals H and J on terminal strip
1T. If trigger hold is not desired, remove and re-
tain jumper link.
3. Route cable from welding power source positive
output terminal, through reed relay, and connect
to positive (+) terminal of secondary contactor
(see Figure 3-2 and 3-8).
4. Route lug end of electrode holder cable through
unit front panel, and connect to remaining termi-
nal of secondary contactor.
5. Reinstall and secure wrapper.
Reed
Relay
Weld
Output
Cable
Secondary
Conductor
Trigger Cord
Workpiece
Terminal Strip 1T
Ref. SA-111 218-A
Welding
Power
Source
Figure 3-2. DC SMAW Electrode Positive
Connections
B. DC Electrode Negative Connections
1. Remove wrapper from unit.
2. If trigger hold is desired be sure jumper link is in
place between terminal H and J on terminal strip
1T. If trigger hold is not desired, remove and re-
tain jumper link.
3. Route lug end of electrode holder cable through
reed relay, and connect to positive (+) terminal of
secondary contactor (see Figures 3-3 and 3-8)
4. Route cable from welding power source negative
output terminal, through unit front panel, and con-
nect to remaining terminal of secondary contac-
tor.
5. Reinstall and secure wrapper.
Reed
Relay
Weld Output
Terminal
Cable
Strip 1T
Secondary
Contactor
Trigger Cord
Welding
Power
Source
Workpiece
Ref. SA-111 218-A
Figure 3-3. DC SMAW Electrode Negative
Connections
3-5. WELD OUTPUT CONNECTIONS FOR GAS
METAL ARC WELDING (GMAW)
WARNING: ELECTRIC SHOCK can kill.
• Do not touch live electrical parts.
• Shut down wire feeder and welding power
source, and disconnect input power employ-
ing lockout/tagging procedures before install-
ing and connecting unit.
Lockout/tagging procedures consist of pad-
locking line disconnect switch in open position,
removing fuses from fuse box, or shutting off
and red-tagging circuit breaker or other discon-
necting device.
CAUTION: INCORRECT POLARITY will
damage contactor.
• Magnetic blowout feature requires positive
polarity at positive contactor terminal.
IMPORTANT: Refer to the welding power source Own-
er’s Manual for proper cable information. Obtain or
make proper length weld cables for this installation. See
wire feeder and welding power source Owner’s Manuals
for connection points and necessary associated infor-
mation.
OM-534 Page 4
1. Remove wrapper from unit.
2. Remove jumper link between terminals H and J
on terminal strip 1T. Retain jumper link for future
use.
3. For DC Electrode Positive Connections:
a. Route cable from welding power source posi-
tive output terminal, through reed relay, and
connect to positive (+) terminal of secondary
contactor (see Figures 3-4 and 3-8).
b. Route end of other weld output cable through
unit front panel and connect to remaining termi-
nal of secondary contactor.
c. Connect remaining end of cable to wire drive
assembly.
4. For DC Electrode Negative Connections:
a. Route end of one weld output cable through unit
rear panel and connect to positive (+) terminal
of secondary contactor (see Figures 3-5 and
3-8).
b. Connect remaining end of cable to wire drive
assembly.
c. Route cable from welding power source nega-
tive output terminal, through unit front panel,
and connect to remaining terminal of secondary
contactor.
5. Reinstall and secure wrapper.
Reed
Relay
Terminal
Strip 1T
Secondary
Contactor
Trigger
Extension
Cord
Trigger
Cord
Wire
Drive
Assembly
Welding
Power
Source
Workpiece
Ref. SA-111 217-A
Figure 3-4. DC GMAW Electrode Positive
Connections
Reed
Relay
Terminal
Strip 1T
Secondary
Contactor
Wire Drive
Assembly
Trigger Cord
Trigger
Extension Cord
Workpiece
Ref. SA-111 217-A
Figure 3-5. DC GMAW Electrode Negative
Connections
3-6. WELD OUTPUT CONNECTIONS FOR AC
SHIELDED METAL ARC WELDING (SMAW)
WARNING: ELECTRIC SHOCK can kill.
• Do not touch live electrical parts.
• Shut down welding power source, and dis-
connect input power employing lockout/tag-
ging procedures before installing and con-
necting unit.
Lockout/tagging procedures consist of pad-
locking line disconnect switch in open position,
removing fuses from fuse box, or shutting off
and red-tagging circuit breaker or other discon-
necting device.
IMPORTANT: Refer to the welding power source Own-
er’s Manual for proper cable information, connection
points, and necessary associated information. Obtain or
make proper length weld cables for this installation.
1. Remove wrapper from unit.
2. Remove jumper link between terminals H and J
on terminal strip 1T. Retain jumper link for future
use.
3. Remove reed relay securing hardware. Move
relay away from rear panel opening towards 1T.
Line up with existing holes and secure (see Fig-
ure 3-8).
CAUTION: AC WELD OUTPUT can damage
reed relay.
• Do not route weld cable through reed relay
when using AC weld output
The relay turns on and off with each alternation
of current which could cause premature failure
of relay if left in circuit.
4. Route cable from welding power source elec-
trode output terminal, through unit rear panel,
and connect to positive (+) terminal of secondary
contactor (see Figure 3-8).
OM-534 Page 5
To Trigger
Extension Cord
GMAW
Trigger Cord
To Plug On Gun
To Trigger Receptacle
On Wire Feeder
GMAW
Trigger Extension
Cord
To Trigger Cord
To Trigger Receptacle
On Secondary Contactor
Pilot Light
Trigger
Receptacle
SA-111 186-A SA-110 488-A
Figure 3-6. Trigger Connections
5. Route lug end of electrode holder cable through
unit front panel, and connect to remaining termi-
nal of secondary contactor.
6. Reinstall and secure wrapper.
3-7. TRIGGER CONNECTIONS (Figure 3-6)
WARNING: ELECTRIC SHOCK can kill.
• Do not touch live electrical parts.
• Shut down wire feeder (if applicable) and
welding power source, and disconnect input
power employing lockout/tagging procedures
before installing and connecting unit.
Lockout/tagging procedures consist of pad-
locking line disconnect switch in open position,
removing fuses from fuse box, or shutting off
and red-tagging circuit breaker or other discon-
necting device.
Select and obtain correct type and length trigger cord
and trigger cord extension, if applicable, for desired
application.
A. Shielded Metal Arc Welding (SMAW)
1. Connect 5-pin Amphenol plug from trigger cord
into 5-socket receptacle on front of unit as fol-
lows: align keyway, insert plug, and rotate
threaded collar fully clockwise.
2. Tape or tie trigger cord onto electrode holder weld
cable at several places.
3. Position trigger switch onto electrode holder and
tape or tie to secure.
B. Gas Metal Arc Welding (GMAW)
1. Connect 5-pin Amphenol plug from trigger exten-
sion cord into 5-socket receptacle on front of unit
as follows: align keyway, insert plug, and rotate
threaded collar fully clockwise.
2. Tape or tie trigger extension cord onto weld cable
attached to wire drive motor.
3. Connect 5-pin plug from trigger cord into 5-sock-
et free-hanging receptacle onto trigger extension
cord as follows: align keyway, insert plug, and ro-
tate threaded collar fully clockwise.
4. Connect 2-pin Amp plug from trigger cord into
TRIGGER receptacle on wire feeder as follows:
align keyway, insert plug, and rotate threaded
collar fully clockwise.
5. Insert plug from welding gun into 2-socket free-
hanging receptacle on trigger cord and rotate col-
lar clockwise.
6. Tape or tie all leads so that they do not interfere
with wire feed.
3-8. INPUT POWER CONNECTIONS (Figures 3-7
and 3-8)
Strain Relief
115 Volts AC Cord
SA-110 492-A
Figure 3-7. Rear View
OM-534 Page 6
Fuse F1
Strain
Relief
Terminal
Strip 1T
Reed Relay
Positive (+)
Terminal
Trigger
Receptacle
RC1
Pilot Light PL1
Secondary
Contactor W
SA-110 490-A
Reed Relay
Position For
AC SMAW
Figure 3-8. Component Location
A. 115 Volts AC Connections
The unit is shipped prepared for using 115 Volts AC in-
put power. To energize the unit, connect plug to a prop-
erly grounded and protected (fuses or circuit breakers)
115 VAC receptacle.
B. 12 Volts DC Connections
WARNING: ELECTRIC SHOCK can kill.
• Do not touch live electrical parts.
• Shut down unit, wire feeder (if applicable) and
welding power source, and disconnect input
power employing lockout/tagging procedures
before installing and connecting unit.
Lockout/tagging procedures consist of remov-
ing input power plug from receptacle, padlock-
ing line disconnect switch in open position, re-
moving fuses from fuse box, or shutting off and
red-tagging circuit breaker or other disconnect-
ing device.
The unit can be modified to use 12 Volts DC input power.
To modify unit proceed as follows:
1. Remove wrapper from unit.
2. Disconnect 115 volts ac cord from terminal strip
1T and chassis ground.
3. Loosen screws on cable clamp and remove 115
VAC cord from unit. Retain cord for future use.
4. Remove jumper link between terminals 1TC and
1TD. Retain jumper link for future use.
5. Route 2-conductor cord (not supplied) through
cable clamp to 1T. Tighten cable clamp screws.
6. Connect 2-conductor cord between 1TD and
1TE. Polarity is not important.
7. Reinstall and secure wrapper.
8. Connect 2-conductor cord to 12 VDC power sup-
ply.
OM-534 Page 7
SECTION 4 − SEQUENCE OF OPERATION
WARNING: ELECTRIC SHOCK can kill;
MOVING PARTS can cause serious injury;
IMPROPER AIRFLOW AND EXPOSURE TO
ENVIRONMENT can damage internal parts.
• Do not touch live electrical parts.
• Keep away from moving parts.
• Keep all covers and panels in place while
operating.
Warranty is void if the unit is operated with any
portion of the outer enclosure removed.
ARC RAYS, SPARKS, AND HOT SURFACES
can burn eyes and skin; NOISE can damage
hearing.
• Wear correct eye, ear, and body protection.
FUMES AND GASES can seriously harm
your health.
• Keep your head out of the fumes.
• Ventilate to keep from breathing fumes and
gases.
• If ventilation is inadequate, use approved
breathing device.
WELDING WIRE can cause puncture
wounds.
• Do not point gun toward any part of the body,
any conductive surface, or other personnel.
HOT METAL, SPATTER, AND SLAG can
cause fire and burns.
• Watch for fire.
• Keep a fire extinguisher nearby, and know
how to use it.
• Do not use near flammable material.
• Allow work and equipment to cool before
handling.
MAGNETIC FIELDS FROM HIGH CUR-
RENTS can affect pacemaker operation.
• Wearers should consult their doctor before
going near arc welding, gouging, or spot
welding operations.
See Section 1 - Safety Rules For Operation Of
Arc Welding Power Source for basic welding
safety information.
4-1. SHIELDED METAL ARC WELDING (SMAW)
WARNING: Read and follow safety informa-
tion at beginning of entire Section 4 before
proceeding.
1. Make all necessary connections as instructed in
Section 3.
2. Wear dry insulating gloves and clothing, and
wear welding helmet with proper filter lens ac-
cording to ANSI Z49.1.
3. Energize welding power source.
4. Press and hold trigger switch on electrode holder.
The secondary contactor should energize and
the pilot light should turn on.
IMPORTANT: The pilot light on the unit front panel will
light whenever the secondary contactor is energized.
5. For DC SMAW: If trigger hold jumper link is be-
tween 1TH and 1TJ, the trigger switch can be re-
leased once an arc is established.
For AC SMAW: The trigger switch must be held
closed while welding.
6. Break arc to stop welding and open secondary
contactor. The pilot light should turn off.
7. Shut down welding power source.
4-2. GAS METAL ARC WELDING (GMAW)
WARNING: Read and follow safety informa-
tion at beginning of entire Section 4 before
proceeding.
1. Make all necessary connections as instructed in
Section 3.
2. Turn on shielding gas if applicable.
3. Wear dry insulating gloves and clothing, and
wear welding helmet with proper filter lens ac-
cording to ANSI Z49.1.
4. Energize wire feeder on welding power source.
5. Press and hold trigger switch on gun. The sec-
ondary contactor should energize, pilot light
should turn on and wire should feed.
6. Start welding.
7. To stop welding, release trigger switch. Second-
ary contactor opens and the pilot light turns off.
8. Shut down wire feeder and welding power
source.
9. Turn of shielding gas if applicable
WARNING: HIGH CONCENTRATION OF
SHIELDING GASES can harm health or kill.
• Shut off gas supply when not in use.
OM-534 Page 8
SECTION 5 − MAINTENANCE & TROUBLESHOOTING
IMPORTANT: Every six months inspect the labels on
this unit for legibility. All precautionary labels must be
maintained in a clearly readable state and replaced
when necessary. See the Parts List for part numbers of
precautionary labels.
5-1. INSPECTION AND UPKEEP
WARNING: ELECTRIC SHOCK can kill.
• Do not touch live electrical parts.
• Shut down unit, wire feeder (if applicable),
and welding power source and disconnect in-
put power employing lockout/tagging proce-
dures before inspecting, maintaining, or serv-
icing.
Lockout/tagging procedures consist of pad-
locking line disconnect switch in open position,
removing fuses from fuse box, or shutting off
and red-tagging circuit breaker or other discon-
necting device.
HOT SURFACES can cause severe burns.
• Allow cooling period before servicing.
Maintenance and troubleshooting to be per-
formed only by qualified persons.
Usage and shop conditions will determine the frequency
and type of maintenance. Inspect equipment every six
months as follows:
1. Remove grease and grime from components; re-
move moisture from electrical parts and cables.
2. Check contactor contacts for wear. Replace con-
tactor if contacts are worn.
3. Inspect cables for breaks in insulation, and en-
sure that all connections are clean and tight. Re-
pair or replace cables if insulation breaks are
present. Clean and tighten connections at each
inspection.
5-2. OVERLOAD PROTECTION
WARNING: ELECTRIC SHOCK can kill.
• Do not touch live electrical parts.
• Shut down unit, wire feeder (if applicable),
and welding power source, and disconnect in-
put power employing lockout/tagging proce-
dures before internally inspecting or servic-
ing.
Lockout/tagging procedures consist of pad-
locking line disconnect switch in open position,
removing fuses from fuse box, or shutting off
and red-tagging circuit breaker or other discon-
necting device.
CAUTION: INCORRECT FUSE can damage
unit.
• Use only replacement fuse of same size,
type, and rating (see Parts List).
This unit is equipped with a fuse F1 located inside the
unit for overload protection (see Figure 3-8). If this fuse
should open, the unit would be completely inoperative.
To check and replace the fuse, it is necessary to remove
the wrapper from the unit.
5-3. TROUBLESHOOTING
WARNING: ELECTRIC SHOCK can kill.
• Do not touch live electrical parts.
• Shut down unit, and disconnect input power
employing lockout/tagging procedures be-
fore inspecting, maintaining, or servicing.
Lockout/tagging procedures consist of pad-
locking line disconnect switch in open position,
removing fuses from fuse box, or shutting off
and red-tagging circuit breaker or other discon-
necting device.
HOT SURFACES can cause severe burns.
• Allow cooling period before servicing.
Troubleshooting to be performed only by
qualified persons.
It is assumed that the unit was properly installed accord-
ing to Section 3 of this manual, the operator is familiar
with the function of controls, the welding power source
was working properly, and that the trouble is not related
to the welding process. The following Table is designed
to diagnose and provide remedies for some of the
troubles that may develop in this unit.
Use the table in conjunction with the circuit diagram
while performing troubleshooting procedures. If the
trouble is not remedied after performing these proce-
dures, the nearest Factory Authorized Service Station
should be contacted. In all cases of equipment malfunc-
tion, the manufacturer’s recommendations should be
strictly followed.
OM-534 Page 9
Table 5-1. Troubleshooting
TROUBLE PROBABLE CAUSE REMEDY
Secondary contactor does not
close.
Fuse F1 open. Replace fuse (see Section 5-2)
Loose trigger connections. Check all trigger connections.
Trigger switch not working. Replace trigger switch.
Secondary contactor does not
open when arc is broken.
Jumper link on 1T. Check jumper link placement according to pro-
cess used. For DC SMAW see Section 3-3; AC
SMAW see Section 3-5; or GMAW see Section
3-4.
Secondary contactor does not
open.
Control relay CR1 not working. Replace CR1.
Trigger switch not working. Replace trigger switch.
SECTION 6 − ELECTRICAL DIAGRAM
Circuit Diagram No. SA-110 364
Diagram 6-1. Circuit Diagram
OM-534 Page 10
SECTION 7 − PARTS LIST
SA-110 490-A
12345
6
7
8
9
10
11
12
13
11
12
16
1718
19
1415
Figure 7-1. Complete Assembly
OM-534 Page 11
Description Quantity
Part
No.
Dia.
Mkgs.
Figure 7-1. Complete Assembly108 921
Item
No.
1 012 571 HOLDER, fuse mintr 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2 F1 *012 634 FUSE, mintr gl 3A 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3 1T 038 785 STRIP, term 3P 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4 VR1 030 759 VARISTOR, .25W 24VDC 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5 T1 090 465 TRANSFORMER, sig 115V 24VCT 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6 110 184 CASE SECTION, bottom/front/rear 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
+110 183 WRAPPER 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
134 327 LABEL, warning general precautionary 1. . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 RC1 035 523 RECEPTACLE, 5skt MS-3102A-16S-8S 1. . . . . . . . . . . . . . . . . . . . . . . . . . .
8 D1 026 202 DIODE, 1A 400V SP 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9 PL1 083 168 LIGHT, indicator red lens 9-14V 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10 CR1 044 588 RELAY, encl 12VDC 3PDT 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
11 010 494 BUSHING, snap-In nyl 1.375 ID x 1.750 mtg hole 2. . . . . . . . . . . . . . . . . .
12 057 358 BUSHING, snap-In nyl 1.000 ID x 1.375 mtg hole 2. . . . . . . . . . . . . . . . . .
13 110 180 BRACKET, mtg contactor 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
14 W 110 361 CONTACTOR, 12VDC 1PST on-off 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
15 REED 140 786 SWITCH, reed 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
110 176 SPACER 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
16 038 782 BLOCK, term 20A 10P 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
601 219 LINK, jumper 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
17 115 104 CONNECTOR, clamp cable .500 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
18 096 822 CORD, pwr 10ft 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
19 SR1 035 704 RECTIFIER, integ 40A 800V 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
110 179 BRACKET, mtg control 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
NAMEPLATE, (order by model and style number) 1. . . . . . . . . . . . . . . . . .
*Recommended Spare Parts.
+When ordering a component originally displaying a precautionary label, the label should also be ordered.
BE SURE TO PROVIDE MODEL AND STYLE NUMBER WHEN ORDERING REPLACEMENT PARTS.
/