7
IV. IMPORTANT CHECKLIST
To confirm that the various components (control, head,
carriage, and power supply) have been properly inter-
connected, it is imperative that the following tests be
performed BEFORE operation starts.
Note: Failure to perform these tests may result in dam-
age to the printed circuit boards in the control.
A. PREPARATORY INSTRUCTIONS
Precautionary measures should be taken to provide
maximum protection against electrical shock. Be
sure that all power is off by opening the line (wall)
disconnect switch. To be doubly safe, check your
input leads with a voltmeter to make sure that all
power is OFF.
1. Remove the cover (5 screws) from the UEC-8 Con-
trol.
2. Remove the two printed circuit boards (P/N's 677330
& 675332) from inside the UEC-8.
3. The following readings should be taken after all equip-
ment has been installed and interconnected, BEFORE
POWER IS APPLIED to the system, and WITH
PRINTED CIRCUIT BOARDS REMOVED.
B. TEST FOR INPUT POWER CONNECTION
1. Place "MLS" switch in the ON position.
2. Place ohmmeter to the highest resistance scale.
3. Check for continuity between TB1-3 and ground stud;
then check for continuity between TB1-1 and ground
stud. There should be a small deflection when the
meter leads are first connected to these points; then
both readings should be infinity.
C. TEST FOR CONTACTOR, CARRIAGE AND FLUX
GATE CONNECTION
1. Place carriage travel and flux gate switches in the
"OFF" position, ("MLS" switch ON).
2. Place ohmmeter on Rx-1 scale. Check for continuity
between TB1-3 and the center terminal of CTS switch.
Reading should be approx. 1000 ohms (for "J" Gov.).
3. Check for continuity between TB1-3 and the red wire
on WSSS switch. Reading should be approx. 40
ohms. If flux gate is used, check for continuity be-
tween TB 1-3 and the center terminal of the Flux
switch. Readings should be approx. 40 ohms.
D. TEST FOR VOLTMETER AND AMMETER CON-
NECTIONS
1. If hookup is made to a DC power supply:
a. Place the positive meter lead on TB1-5 and nega-
tive meter lead on TB1-6. Reading should be
approx. 500 ohms, but this reading will vary con-
siderably from power supply to power supply.
receptacle (P8) on the side of the control. Connect
the lead tagged No. 1 to busbar and lead No. 2 to the
workpiece or fixture (see Note 3 on Fig. 1).
4. Connect the plug end of the carriage governor cable to
receptacle (P9) on the control.
NOTE: When using "J" Gov. P/N 953534 cable
997965 is required (see Section III-B-5). In-
sert the lugged end through the strain relief
on the back of the "J" Governor and connect
to TB1 in governor as follows: Red to TB1-8;
White to TB1-9; Black to TB1-10; Green to
ground stud.
F. CONNECTIONS FOR DUAL WIRE OPERATION
1. DC/AC Connection (see Fig. 1). With the numerous
power supplies available for use with the UEC-8, it is
suggested in dual-wire applications that the operator
use a DC unit as the lead power supply source to
provide weld penetration. An AC unit should be used
as the trail power supply to give the weld a cosmetic
finish.
G.IMPORTANT WIRING/OPERATING MODIFICA-
TION USING EH-10A MOTOR
As noted in this booklet, one of the welding heads the
UEC-8 is recommended for use with is the new EH-10A
motor that can accommodate wire speeds from 0-1000
ipm. As a result, the Wire Feed Speed potentiometer
may not have the fine adjustment (or resolution) range
settings that you may prefer, and would normally be af-
forded the other motors with lower wire speed (ipm)
ranges.
If finer resolution in the "speed" potentiometer is desired,
and you do not plan to operate the control at wire feed
speeds above 500 ipm, you can modify the circuitry to
spread the operating range of this "speed control". To
do this, add a resistor (100K ohm, 1/4 watt) to the Wire
Speed potentiometer as shown in the schematic dia-
gram. Remember, if this modification is made, that
the effective operating range of the potentiometer
will be changed from 0-1000 ipm to 0-500 ipm.
