DATA PRECISION 5740 - Power Supply Verification; Counter-Latch-Display Chain Check

72-1002
Model 5740 COUNTER
Table 4 2
OVERALL SYSTEM PERFORMANCE CHECK (60 HZ)
S4
(Slide Switch)
S3
Manual-Auto Rotary
Display*
SECONDS/FREQ
(0.1Hz Resolution) ICS Gate
000.0600
PERIOD/EVENT
10 PERIODS AVGD
100 PERIODS AVGD
016666.6
66666.66 & Overflow
SECONDS/FREQ
RESET
COUNT
After 30 Seconds
HOLD
COUNT
00000.00
Increment at 100/sec rate
00030.00 ± 3%
Continue at 100/sec rate
PERIOD/EVENT
RESET
COUNT
0000000 (No D.P.)
Increment at 60/sec rate
"Add ± [1 count + time base stability + line frequency stability (approx. 0.1% stiort term)]
4.5 POWER SUPPLY CHECK 4 5 2 Procedure
4.5.1 General
a) All tests are made vrith respect to
TP7
b) Non-conformance of a povrer supply
measurement to specification may result
from a power supply circuit malfunction
or a malfunction in one of the driven
loads. In general, a higher-than-speci-
fication value indicates a power supply
malfunction, (or need for adjustment),
whereas a less-than spec value may be
caused by either a power supply malfunc
tion (a need for adjustment) or load
malfunction.
c) Figure 4-2 summarizes the testing
strategy for isolating power supply mal
functions. See Drawing D75-1000 for
circuit details, and parts list for re
placement ordering information.
CAUTION
HIGH VOLTAGES ARE EXPOSED WHEN
COVER IS REMOVED. OBSERVE PRE
CAUTIONS WHEN MAKING MEASUREMENTS
WITHIN OPEN UNIT.
d) Remove top cover by first removing
cover hold-down screws at rear panel.
Then left cover over front-panel "dim
ples". All test points and component
parts are identified on the top of the
main PC board assembly, and are shown
in Figure U-3.
Position Rotary Switch S3 to FREQ/SEC-
ONDS, and follow the measurement sequence
of Figure 4-2.
4.6 CRYSTAL TIME BASE CHECK
Follow the measurement sequence of Fig
ure 4-4.
4.7 COUNTER-LATCH-DISPLAY CHECK
4.7.1 Sot-Up
Model 5740
Mode (S4): FREQ/SEC position
Rotary (S3): RESET
Timer: Set to zero
4.7.2 Procedure
a) Simultaneously, start timer and posi
tion Model 5740 S3 to SECONDS/EVENTS
b) Observe Model 5740 display. Check to
see that it tracks the value of the Timer
at 10 sec, 120 sec, 180 sec, 300 sec val
ues .
c) If apparent error, signal trace
through Counter-Latch-Display chain as il
lustrated in reference schematic.
COPVRIOHT 197B DATA PRfCISION CORraRATIOM. PRINTED IN THE USA.
4-3