Caution: Use only anhydrous de-
natured ethyl alcohol when cleaning
a. Exterior of Equipment. Inspect the ex-
terior of the equipment. The exterior surfaces
cleaning solvents may react with the
should be free of dust, dirt, grease, and fungus.
insulating material in these switches.
(1) Remove dust and loose dirt with a
clean soft cloth.
(4) When necessary, wash exposed insu-
lating material of all switches with a
small stiff bristled brush and anhy-
(FSN 7930-395-9542) is flammable and
drous denatured ethyl alcohol.
its fumes are toxic. Provide adequate
(5) After washing, recoat the exposed
ventilation. Do not use near a flame.
switch insulating material with a so-
(2) Remove grease, fungus, and ground-
lution of Dow Corning 200 having a
in dirt from the case; use a cloth
viscosity between 50 arid 200
dampened (not wet) with cleaning
centistokes (10 percent solution of
100 viscosity grade Dow Corning
(3) Remove dust or dirt from plugs and
200 in anhydrous denatured ethyl al-
jacks with a brush.
cohol.) This solution will prevent
any leakage due to moisture on these
Caution: Do not press on the meter
surfaces. Do not apply grease or
face (glass) when cleaning; the meter
other lubricant to switch wafers.
may become damaged.
(4) Clean the front panel, meter, and
3-9. Touchup Painting Instructions
control knobs; use a soft clean cloth.
Remove rust and corrosion from metal sur-
If dirt is difficult to remove, dampen
faces by lightly sanding them with fine sand-
the cloth with water; mild soap may
paper. Brush two thin coats of paint on the
be used for more effective cleaning.
bare metal to protect it from further corrosion.
b. Interior of Equipment. Perform the fol-
Refer to the applicable cleaning and refinish-
lowing procedures to remove dust and foreign
ing practices specified in TM 9213.
matter and to prevent leakage.
(1) Remove the two securing screws at
3-10. Visual Inspection
the rear of the vtvm and pull the
When the equipment fails to operate prop-
chassis out of the case.
erly, turn off the power and check for the con-
(2) Blow out dust and foreign matter
ditions listed below. Inspection will save re-
from the vtvm with a low-pressure
pair time and may also avoid further damage.
dry air blower. Be sure that the bind-
Do not check any item with the power on.
ing posts, wiring, and all switches are
a. Wrong settings of switches and controls.
completely free of dust and foreign
b. Damaged, disconnected, or poorly con-
nected power cord.
c. Burned-out fuse. (This condition usually
and front panel with a rag saturated
indicates some other fault.)
in anhydrous denatured ethyl alcohol.