TM 55-6670-200-14&P
Table
3-1.
Troubleshooting
Chart
(continued).
Increase voltage if ac; replace battery if
Low voltage level.
Sensitivity bad on all cells.
dc. NOTE: If voltage does not increase
when turning AC VOLTAGE ADJUST-
MENT knob on power supply panel, re-
place 1H20 tubes in power supply.
Weak 12AU7 or 6072 (12AX7)
Replace weak tubes with spare tubes sup-
tube.
plied with kit.
Excessive
drift
of
O s c i l l a t o r transformer mal-
milliammeter.
Return kit to depot.
function in all cells.
Return kit to depot.
Cell malfunction in one cell.
Erratic needle when ZERO
Turn knob back and forth a few times. If
Dirty or worn potentiometer.
SET knob is turned.
t r o u b l e does not clear, return kit to
depot.
Milliam meter
jitter
Ground cell and cable to locate open
Open ground.
(continuous).
ground. If trouble lies within cell, return
kit to depot.
Dirty dc or ac power cable
Clean and tighten plugs.
plugs or loose connections.
M i l l i a m m e t e r jitter (inter-
Relocate welding power supplies, and the
External interference.
mittent and excessive).
like that cause interference.
Slide wire arm contact broken
Slide wire inoperative.
Return kit to depot.
or not making contact.
Wipe wire with lint free cloth containing
Dirt on wire.
Slide wire erratic.
several drops of alcohol, while rotating
WEIGHT knob.
Return kit to depot.
Loose slide wire contact arm.
S l i d e wire jumps at one
Rotate WEIGHT knob across erratic point
Flat region on wire.
point on scale.
several times. If condition is not remedi-
ed, return kit to depot.
Return kit to depot.
Slide wire dial warped.
Jumpy cell balance needle
D e f e c t i v e CELL BALANCE
on all cells.
Return kit to depot.
switch.
F a u l t y oscillator-amplifier
Return kit to depot.
Return kit to depot.
Faulty power pack filter.
Milliammeter pegs as am-
Short occurs on terminal
plifier cover is secured.
Secure wires properly on terminal strip.
strip.
Return kit to depot.
Defective harness.
3-3
