Miller RHC-3 User manual

cover 8/92 −Ref. ST-141 127-A PRINTED IN USA
Read and follow these instructions and all
safety blocks carefully.
Have only trained and qualified persons
install, operate, or service this unit.
Call your distributor if you do not understand
the directions.
Give this manual to the operator.
For help, call your distributor
or: MILLER ELECTRIC Mfg. Co., P.O. Box
1079, Appleton, WI 54912 414-734-9821
OWNER’S
MANUAL
May 1993 Form: OM-823H
Effective With Serial No. KB055102
Remote Hand Controls
For Remote Amperage Or Voltage Control
RHC-14 And RHC-23 Models Add Output (Contactor) Control
Primarily For SMAW Welding
20 ft (6 m) Interconnecting Cord
RHC-3, RHC-3-2, RHC-3GD25B,
RHCS-3, RHC-3-GD34A, RHC-14,
And RHC-23

OM-823H −5/93
TABLE OF CONTENTS
SECTION 1 −SAFETY INFORMATION 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 2 −SPECIFICATIONS 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 3 −INSTALLATION
3-1. Location 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-2. Interconnections 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 4 −OPERATION
4-1. Control Operation 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 5 −MAINTENANCE & TROUBLESHOOTING
5-1. Routine Maintenance 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5-2. Troubleshooting 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 6 −ELECTRICAL DIAGRAMS 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 7 −PARTS LIST
Figure 7-1. Complete Assembly (RHC-3 Illustrated) 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

OM-823 Page 1
SECTION 1 −SAFETY INFORMATION
mod1.1 2/93
Read all safety messages throughout this manual.
Obey all safety messages to avoid injury.
Learn the meaning of WARNING and CAUTION.
1 Safety Alert Symbol
2 Signal Word
WARNING means possible death
or serious injury can happen.
CAUTION means possible minor
injury or equipment damage can
happen.
3 Statement Of Hazard And Re-
sult
4 Safety Instructions To Avoid
Hazard
5 Hazard Symbol (If Available)
6 Safety Banner
Read safety blocks for each sym-
bol shown.
7 NOTE
Special instructions for best oper-
ation −not related to safety.
2
NOTE
ELECTRIC SHOCK can kill.
•Do not touch live electrical parts.
•Disconnect input power before
installing or servicing.
WARNING
READ SAFETY BLOCKS at start of
Section 3-1 before proceeding.
WARNING
5
4
6
7
1 2
CAUTION
MOVING PARTS can injure.
•Keep away from moving parts.
•Keep all panels and covers closed
when operating.
3
Turn Off switch when using high frequency.
Figure 1-1. Safety Information
SECTION 2 −SPECIFICATIONS
Table 2-1. Remote Hand Control
Specification Description
Model Description RHC: Remote Hand Control; GD: For Use With Welding Generators Only; Suffix Of −2: Used To Control
Two Identical Welding Power Sources Or Welding Generators At The Same Time.
Interconnecting Cord 20 ft (6 m)
Overall Dimensions See Figure 3-1
SECTION 3 −INSTALLATION
3-1. Location
Ref. ST-141 127-A
1 Remote Hand Control
Install RHC onto wall, or place on
bench or other convenient location.
1
B
C
A
B
C
7-1/2
9-1/2
8-3/4
Inches
191
241
222
Millimeters
A
Figure 3-1. Overall Dimensions

OM-823 Page 2
3-2. Interconnections
ST-141 127-A
Turn Off welding power source, or
stop engine on welding generator.
1 Remote Hand Control
2 Interconnecting Cord
Units are equipped with a 20 ft (6
m) multiconductor cord (unless
otherwise specified). If a longer
cord is required, see Table 3-1.
3 Twistlock Plug
Make connection to matching re-
ceptacle on welding power source
or welding generator by inserting
plug, and turning cap in a clockwise
direction as far as it will go.
4 14- Or 5-Pin Amphenol Plug
Make connection to matching re-
ceptacle on welding power source
or welding generator by aligning
keyway, inserting plug, and rotating
threaded collar fully clockwise.
1
2
3
4
Figure 3-2. Interconnections
Table 3-1. Interconnecting Cord Conductor Length And Size
Amperage Or Voltage Control
Cord Length Conductor Size*
Up to 20 ft (6 m) No. 16
Up to 20 ft (6 m) (GD Models) No. 14
21 to 100 ft (6 to 30 m) (GD Models) No. 12
21 to 50 ft (6 to 15 m) No. 14
51 to 100 ft (16 to 31 m) No. 12
101 to 200 ft (31 to 61 m) No. 10
*AWG −American Wire Gauge
SECTION 4 −OPERATION
WARNING
ELECTRIC SHOCK can kill.
•Always wear dry insulating gloves.
•Insulate yourself from work and ground.
•Do not touch live electrical parts.
•Keep all panels and covers securely in place.
FUMES AND GASES can be hazardous
to your health.
•Keep your head out of the fumes.
•Ventilate area, or use breathing device.
•Read Material Safety Data Sheets (MSDSs) and
manufacturer’s instructions for material used.
WELDING can cause fire or explosion.
•Do not weld near flammable material.
•Watch for fire; keep extinguisher nearby.
•Do not locate unit over combustible surfaces.
•Do not weld on closed containers.
•Allow work and equipment to cool before handling.
ARC RAYS can burn eyes and skin;
NOISE can damage hearing.
•Wear welding helmet with correct shade of filter.
•Wear correct eye, ear, and body protection.
MAGNETIC FIELDS FROM HIGH CUR-
RENTS can affect pacemaker operation.
•Pacemaker wearers keep away.
•Wearers should consult their doctor before going
near arc welding, gouging, or spot welding opera-
tions.
See Safety Precautions at beginning of welding power
source or welding generator manual for basic welding
safety information.
swarn6.1* 10/91

OM-823 Page 3
4-1. Control Operation
See welding power source or welding generator Owner’s Manual to determine if
Remote Hand Control will act as a fine Amperage or Voltage control, or as a full
range Amperage or Voltage control.
NOTE
A. Adjusting Amperage Or Voltage Without Output (Contactor) Control
Ref. ST-122 023-A / Ref. ST-141 127-A / ST-039 411-D
EXAMPLE Of Fine Remote Amperage Control Without Output (Contactor) Control
Set Switch Set Control Adjust Remote Amperage
Or
EXAMPLE Of Full Remote Amperage Control Without Output (Contactor) Control
Min
(40 A) Max (200 A)
In Example: Min = 40 A In Range B
Percentage Of Output = 50%
Max = 200 A In Range B (100% of 200 A)
Set Switch Control Setting Adjust Remote Amperage
Min
(40 A) Max (375 A)
In Example: Min = 40 A In Range B
Percentage Of Output = 50%
Max = 375 A In Range B (100% Of 375 A)
Does Not Matter
Figure 4-1. Examples Of Amperage Or Voltage Adjustment Without Output (Contactor) Control

OM-823 Page 4
B. Adjusting Amperage Or Voltage With Output (Contactor) Control (RHC-14 And RHC-23 Models Only)
WARNING
ELECTRIC SHOCK can kill.
•Do not touch live electrical parts.
•Do not touch weld output terminals when contactor is energized.
•Do not touch electrode and work clamp at the same time. swarn7.1 10/91
Ref. ST-159 059 / Ref. ST-130 214-A
Set Switches Set Control
EXAMPLE Of Fine Remote Amperage Control With Output (Contactor) Control
Min
(5 A) Max (200 A)
Place switch in On position for open-circuit
voltage. When switch is in Off position no
weld output voltage is present.
In Example: Min = 5 A
Percentage of Output = 100%
Max = 200 A (100% of 200 A)
Or
Set Switches Control Setting
Min
(5 A) Max (375 A)
In Example: Min = 5 A
Percentage of Output = 100%
Max = 375 A (100% of 375 A)
EXAMPLE Of Full Remote Amperage Control With Output (Contactor) Control
Place switch in On position for open-circuit
voltage. When switch is in Off position no
weld output voltage is present.
Does Not Matter
Figure 4-2. Examples Of Amperage Or Voltage Adjustment With Output (Contactor) Control

OM-823 Page 5
C. Remote Hand Control Of Two Welding Power Sources Or Welding Generators
Models with the suffix -2, are designed to control two identical welding power sources or welding generators at the
same time. Turning the knob on the remote hand control adjusts the amperage or voltage on each welding power
source or welding generator to the same output setting. Refer to welding power source or welding generator Owner’s
Manual for additional information.
SECTION 5 −MAINTENANCE & TROUBLESHOOTING
WARNING
ELECTRIC SHOCK can kill.
•Do not touch live electrical parts.
•Turn Off welding power source, and disconnect
remote control before inspecting, maintaining, or
servicing.
HOT PARTS can cause severe burns.
•Allow cooling period before maintaining or servicing.
Maintenanceand troubleshooting to be performed only
by qualified persons.
swarn8.1* 2/93
5-1. Routine Maintenance
Turn Off all power before
maintaining.
3 Months
Replace
Unreadable
Labels
Everyday
ST-141 127-A
Turn
Control
14-Pin Cord
Replace
Cracked
Parts
Figure 5-1. Maintenance Schedule
5-2. Troubleshooting
Table 5-1. Welding Trouble
Trouble Remedy Section
No amperage or voltage control. Set switches and controls on welding power source or generator. 4, *
Check weld output on welding power source or generator. *
Secure cord connections or replace cords, if necessary. −−
No Output (Contactor) control. Switch in wrong position or control not so equipped. Figure 4-2
*See welding power source or generator Owner’s Manual.

OM-823 Page 6
SECTION 6 −ELECTRICAL DIAGRAMS
SA-150 670
Figure 6-1. Circuit Diagram For RHC-3
Ref. SA-150 671
Figure 6-2. Circuit Diagram For RHCS-3

OM-823 Page 7
SA-094 231-A
Figure 6-3. Circuit Diagram For RHC-3-GD34A
SA-094 232-A
Figure 6-4. Circuit Diagram For RHC-3-GD25B
SA-053 656-A
Figure 6-5. Circuit Diagram For RHC-14 And RHC-23