ESAB Welding System Part No. 677190 User Manual
4
I. INTRODUCTION
1. The UEC-8 electronic welding control P/N 677190 is
designed for a wide range of Subarc† welding appli-
cations, and can be used with either a constant-volt-
age or a constant-current power supply as follows:
cations, and can be used with either a constant-volt-
age or a constant-current power supply as follows:
650 cvcc, 60 hz.*....................................P/N36006
653 cvcc, 60 hz.*....................................P/N36234
653 cvcc, 60 hz.*....................................P/N36234
* If higher welding currents are desired, a kit is avail-
able from ESAB that allows you to parallel two 650
cvcc units to provide up to 1300 amperes output.
cvcc units to provide up to 1300 amperes output.
† If the UEC-8 is to be used with power sources no
longer manufactured (or recommended), please con-
tact your ESAB Welding Supplier or the Factory and
request a copy of edition F-12-747-"E". The "E" edi-
tion contains historical information and requirements
previously provided for low-range Subarc and Mig
welding applications.
tact your ESAB Welding Supplier or the Factory and
request a copy of edition F-12-747-"E". The "E" edi-
tion contains historical information and requirements
previously provided for low-range Subarc and Mig
welding applications.
The UEC-8 is recommended for use with the following
welding heads: EH-11 (for either constant-voltage or
constant-current operation) or the EH-10 or 10A (for con-
stant-voltage operation only). The control utilizes two
solid-state printed circuit boards (described in Sec. II-C)
to obtain excellent wire feed speed regulation. The con-
trol is designed to be used for "Touch Work" (with op-
tional D.C. touch work kit) and "scratch" starts (for AC
or DC). In scratch starting the carriage is moving before
the wire has contacted the work; in touch-work starting,
the wire inches down to the work and the carriage does
not move until the welding arc has been initiated.
welding heads: EH-11 (for either constant-voltage or
constant-current operation) or the EH-10 or 10A (for con-
stant-voltage operation only). The control utilizes two
solid-state printed circuit boards (described in Sec. II-C)
to obtain excellent wire feed speed regulation. The con-
trol is designed to be used for "Touch Work" (with op-
tional D.C. touch work kit) and "scratch" starts (for AC
or DC). In scratch starting the carriage is moving before
the wire has contacted the work; in touch-work starting,
the wire inches down to the work and the carriage does
not move until the welding arc has been initiated.
II. DESCRIPTION
A. FRONT PANEL CONTROLS
1. Main Line Switch -- double pole single throw; breaks
1. Main Line Switch -- double pole single throw; breaks
both sides of 120 VAC power to control. Pilot light
built in 5 ampere Slo-Blo fuse in hot side of AC lines.
built in 5 ampere Slo-Blo fuse in hot side of AC lines.
2. Voltage Control Potentiometer--allows remote ad-
justment of output voltage.
3. Wire Feed Speed Potentiometer -- controls rate of
wire feed speed during welding. This potentiometer
dial contains a 10 turn vernier calibrated from 0 to
100, and a computer which indicates the number of
turns (0 to 9) giving a total of 1000 increment settings
for accurate repeatable wire speed conditions.
dial contains a 10 turn vernier calibrated from 0 to
100, and a computer which indicates the number of
turns (0 to 9) giving a total of 1000 increment settings
for accurate repeatable wire speed conditions.
4. Inch Speed Potentiometer -- screwdriver adjustment
controls rate of wire feed speed during inching.
5. Inch Up-Down Switch--spring loaded to center off
position - provides signal to allow motor to inch wire
up or down.
up or down.
6. Carriage Auto-Manual-Off Switch---when a compat-
ible carriage governor is connected to the UEC-8,
allows automatic starting and stopping of carriage in
"Auto" position. In "Manual" position, carriage drive
is energized continuously. In center "Off" position,
there is no carriage operation.
"Auto" position. In "Manual" position, carriage drive
is energized continuously. In center "Off" position,
there is no carriage operation.
7. Weld Start-Stop Switch--double pole double throw,
no center off position - in. "Start" position is initiates
welding action. In "Stop" position, weld sequence is
terminated.
welding action. In "Stop" position, weld sequence is
terminated.
8. Touch Work Light -- included in optional Touch Work
Kit-lights when wire touches work prior to arc initia-
tion.
tion.
9. Anti-Stick Potentiometer -- located on the left side
panel of the UEC-8. control. The potentiometer con-
trols the length of time the wire is retracted at the end
of the weld cycle, thus allowing the welding wire to
retract a controlled amount. With a clockwise adjust-
ment, the anti-stick time will increase, with a counter-
clockwise adjustment, the anti- stick time will increase,
with a counter-clock wise adjustment, the anti-stick
time will decrease.
trols the length of time the wire is retracted at the end
of the weld cycle, thus allowing the welding wire to
retract a controlled amount. With a clockwise adjust-
ment, the anti-stick time will increase, with a counter-
clockwise adjustment, the anti- stick time will increase,
with a counter-clock wise adjustment, the anti-stick
time will decrease.
B. INTERNAL CONTROLS
1. Sensitivity Potentiometer (See Figure 3) -- an arc
1. Sensitivity Potentiometer (See Figure 3) -- an arc
voltage sensitivity potentiometer is located on the in-
side back panel of the UEC-8 control. The adjust-
ment of this "pot" controls the amount of arc voltage
signal with respect to motor back e.m.f. (electro-mo-
tive force) used; thus controlling motor response to
arc voltage changes.
side back panel of the UEC-8 control. The adjust-
ment of this "pot" controls the amount of arc voltage
signal with respect to motor back e.m.f. (electro-mo-
tive force) used; thus controlling motor response to
arc voltage changes.
2. Weld Power Selector Switch (See Figure 5) -- lo-
cated on the Reversible Governor PC Board - allows
the control to be used with either a constant-current
or a constant-potential power supply. Switch must
be placed in the proper position with respect to
the type of power supply selected.
the control to be used with either a constant-current
or a constant-potential power supply. Switch must
be placed in the proper position with respect to
the type of power supply selected.
C. PRINTED CIRCUIT BOARDS (See Figures 5 and
6)
1. Logical Board (P/N 675330) -- provides basic se-
quencing of wire feed motor, weld contactor and anti-
stick. A 1/2- amp standard fuse to protect the current
detector circuit is located on the right side of the board.
Also the PC board contains two LED* indicator lights.
These lights help in troubleshooting the unit by indi-
cating the state of the voltage and current detector at
all times.
stick. A 1/2- amp standard fuse to protect the current
detector circuit is located on the right side of the board.
Also the PC board contains two LED* indicator lights.
These lights help in troubleshooting the unit by indi-
cating the state of the voltage and current detector at
all times.
2. Reversible Governor Board (P/N 675332) -- solid
state motor speed control. Automatic reversing fea-
ture for retract starts. During welding, if wire stubs to
the plate or the arc is lost the wire will retract (at inch
speed ) and inch down automatically until the arc is
reestablished. A weld power selector switch (see II-
B-2 above) is located on the right side of the PC board.
Also the board contains an LED indicator light to check
proper electrical installation of the wire feed motor.
ture for retract starts. During welding, if wire stubs to
the plate or the arc is lost the wire will retract (at inch
speed ) and inch down automatically until the arc is
reestablished. A weld power selector switch (see II-
B-2 above) is located on the right side of the PC board.
Also the board contains an LED indicator light to check
proper electrical installation of the wire feed motor.
* Light emitting diode