5-4. General Test Requirements
a. Indicator lamps shall be checked to in-
(7) Vary the load in steps of 10 ma from
sure proper setting and security.
10 to 100 ma, and take a voltage
b. Each of the eight plug-in units shall be
reading at each step. These readings
r e m o v e d and the mountings checked to see
should approximate the values in the
t h a t the moulded shells are not cracked or
chart below with suitable allowances
broken, and that the plug-in prongs are not
for possible variations in the input
b e n t . When the plug-in units are replaced,
check to see that the prongs of the plugs enter
smoothly between the contact fingers in the
r e c e p t a c l e s , and without the need of undue
c. Prepare a 20,000-ohm variable resistor by
connecting the two 10,000-ohm variable resis-
tors in series.
5-5. Operational Test
a. Connect the ac input cable t o a power
source of 116 volts, 60 cps, single phase ac.
If a 115-volt ac power source is not available,
use any voltage between 105 and 125 volts and
make allowance when making the tests below.
( 1 ) I n s t a l l a plug-in unit in position 1
on the power supply panel, with the
Note. Aged selenium rectifiers in a unit
word POSITIVE at the top.
will result in slightly lower output voltage
( 2 ) Measure the dc output between ter-
readings as compared with new selerium
minal 1 on terminal board TB1 and
ground. The reading should be ap
(8) Repeat the test given in (1) and (2)
p r o x i m a t e l y 155 volts positive with
above for each of the dc output pos-
respect to ground.
( 3 ) Remove the plug-in unit and reinstall
( 9 ) Maintain the equipment connections
it with the word NEGATIVE at the
specified above. With the output con-
top, and repeat the above test. The
trol at maximum clockwise position
voltage should now be 166 volts nega-
(100), adjust the 20,000-ohm variable
tive with respect to ground.
load for 100 ma as indicated on the
(4) With no load connected, turn the
TS-352/U. The voltage across the
k n o b of the output control rheostat
variable load should vary smoothly as
of the position under test to 100 on
t h e panel output control is varied
from 100 to 0 and back to the 100-
( 5 ) Remove the plug-in unit and connect
a variable load (0 to 20,000 ohms)
and milliammeter in series between
Caution: Do not exceed 100 ma at
terminal 1 of terminal board TB1 and
b. Plug-in units that pass the above tests
leting the connection to ground.
may be returned to service.
Reinstall the plug-in unit.