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FL8400
LEAKAGE TEST
Before returning the unit to the user, perform the
following safety checks:
1. Inspect all lead dress to makes certain that
leads are not pinched or that hardware is not
lodged between the chassis and other metallic
parts in the unit.
2. Be sure that any protective devices such as
nonmetallic
control
knobs,
insulating
fishpapers, cabinet backs, adjustment and
compartmént covers or shields, isolation
resistor-capacity
networks,
mechanical
insulators, etc. Which
were
removed
for
servicing are properly reinstalled.
3. Be sure that no shock hazard exists; check for
leakage current using Simpson
Model 229
Leakage Tester, standard equipment item no.
21641, RCA model WT540A
or use alternate
method
as follows:
plug the power cord
directly into a 120-volt AC receptacle (do not
use an Isolation transformer
for this test).
Using two clip leads, connects a 1500 ohm,
10-watt
resistor
paralleled
by a 0.15uF
capacitor, in series with all exposed metal
cabinet parts and a known earth ground, such
as a water pipe or conduit. Use a VTVM or
VOM
with 1000 ohms
per volt, or higher
sensitivity to measure the AC voltage drop
across the resistor.
(see diagram)
Move the
resistor connection to each exposed metal
part having a return
path to the chassis
(antenna, metal cabinet, screw heads, knobs
and control shafts, escutcheon,
etc.) and
measure
the AC voltage drop across the
resistor. (This test should be performed with
the power switch
in both the on
and off
positions.)
A reading of 0.35 volt RMS
or more
is
excessive and indicates a potential shock
hazard which
must
be corrected
before
returning the unit to the owner.
VOLTAGE
OR + LEAD
TO EXPOSED
METALIC PARTS
SIMPSON MODEL 229 ETC. FOR LEAKAGE TEST
TO EACH EXPOSED
TO AC GROUND SUCH
METAL SURFACE OF "=
) }=———
AS WATER PIPE BX CABLE
UNITUNDER Test
= HIGH
GROUND
CONDUIT ETC.
LEAD
AC SCALE G
0,15uF
TEST PROBE
CONNECT TO KNOWN
EARTH GROUND
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