IET Labs, Inc. RLC Digibridge 1693, User And Service Manual, Page: 139 / 171

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1693 RLC Digibridge
Service and Maintenance
5.4.3 Measurement-Time Checkout
This procedure verifies that the 1693 measurement
rate is functioning properly. All measurements are
made with the default (power-up) values of test fre-
quency and test voltage (1 kHz and 1 V). The proce-
dure determines the time required per measurement
for several operating conditions, without and then
with the high-speed option board. Make a note of
each calculated result for final comparisons to verify
the speed.
Equipment Required:
• 1693 Digibridge without high-speed option.
(To remove it, see paragraph 5.5.3.)
• 1689-9620 high-speed measurement option
board (retrofit or just removed).
• Watch or clock with digital display of seconds
or a sweep second hand
• A suitable DUT such as the 24.9-ohm
Calibration Resistor (used in the examples,
see below).
NOTE: The readings can be expected to vary ±5%
from the examples given, mostly because the manual
timing method is liable to such errors. The method is
adequate for the purpose intended.
1. Switch the POWER ON. Perform the zero-
ing procedure (both open circuit and short
circuit), as described in paragraph 5.4.2 of
the recalibration procedure.
2. Insert the DUT (24.9 ohms ±0.1% for ex-
ample) in the test fixture
A. Press: [FUNCTION] key to select ENTER
function.
B. Press: [2] [4] [.] [9] [=] [SHIFT] [NOM.
VALUE]
C. Press: [.][2] [%] [=] [SHIFT] [BIN NO.]
[0] [1]
D. Press: [MEASURE RATE] (if necessary)
to select SLOW rate.
E. Press: [MEASURE MODE] to select
CONTINUOUS mode.
3. With the watch or clock, time the interval
between the next two keystrokes. The number
of measurements made while the function is
MEASURE will automatically be stored in
“bin sum” for bin 01.
A. Press: [FUNCTION] key to select
MEASURE function.
B. Wait 60 seconds.
C. Press: [FUNCTION] key to select ENTER
function.
D. Press: [SHIFT] [BIN SUM] [0] [1].
4. Read the left-hand display, which is the num-
ber of measurements made in 60 seconds.
(±5% accuracy of timing is assumed.) Use
this number as “x” in the following formula;
retain these results. Note: the right-hand
display should be 1, the bin number being
reported.
Measurement time = T = 60,000 milliseconds/x
For example, if x = 58, then T = 1034 ms ±5%.
5. Clear all “bin sum” registers by pressing [=]
[SHIFT] [BIN SUM] [0] [0] [1] [4]
Note: The Digibridge should confirm the clearing action
by displaying in the left-hand display area.
6. Press: [MEASURE RATE] key to select
MEDIUM rate. Repeat the procedure of steps
3, 4, 5 (as summarized below), for this rate
A. Time the interval between the next two
keystrokes.
B. Press: [FUNCTION] key to select
MEASURE function. Wait 60 seconds.
C. Press: [FUNCTION] key to select ENTER
function.
D. Press: [SHIFT] [BIN SUM] [0] [I].
E. Read the left-hand display, the number of
measurements made in 60 s.
F. Use this number as “x” in the following
formula.
T = 60,000 milliseconds / x
For example, if x = 250, then T = 240 DIS ±5%.
G. Clear “bin sum” registers by pressing [=]
[SHIFT][BIN SUM][0][0][1][4]