IET Labs, Inc. RLC Digibridge 1693 User And Service Manual page 150

1693 RLC Digibridge
444 E XXXX Test frequency and waveform check
failure; the Digibridge will loop, automatically re-
peating the test and updating the display. The digit E
indicates the frequency used in the test. (See below.)
High voltage test signal is used, on range 4.
COMMENT: Measurement, summing of squares ,
and normalization are exactly as described for 555
D XXXX. Also the failure limits for XXXX are the
same (0.250 and 1.00), except for tests 1 and 2, which
have the limits: 0.125 and 1.000.
ANALYSIS PROCEDURE: Check for the generation
of the proper frequency (indicated in code by failure
display, see below).
444 6 XXXX .0118 kHz.
444 5 XXXX .0968 kHz.
444 4: XXXX. 0.480 kHz.
444 3 XXXX. 1.200 kHz.
444 2 XXXX. 6.000 kHz.
444 1 XXXX 6.0606 kHz.
1689-4702 Analog & Control board requires service
by trained personnel.
33333 XXXX. PROM data checksum failure. If
the checksum XXXX is not 0000, check all digital
circuitry, stating with the 6502 microprocessor U30.
Any error on the address or data bus could cause a
checksum error check ROM U35; check RAM U36;
check all of the PLAs U3, U25, U26, U27. Make
sure all socketed chips are seated, otherwise contact
trained personnel to service the Analog & Control
board (1689-4702).
222 F XXXX. Calibration constants check failure;
Digibridge hangs up, but will respond to keyboard
inputs. The digit F is the range in question.
COMMENT: Each check consists of a comparison
between the stored calibration data for the range and
the normal, expected values. The calibration can
be expressed (essentially) as the conductance of the
internal standard resistor. The Digibridge normal-
izes this conductance by dividing it by the nominal
conductance of the standard, and displays the result,
126
XXXX, which should be very close to 1.000. (See
Table 3-7 on page 43.) If XXXX is less than 0.2187 or
more than 1.781, this test fails.
ANALYSIS PROCEDURE: depends upon display;
see below.
NOTE: This is a non-catastrophic failure. If you press
the [C/D] key, the Digibridge will proceed with the
self-check routine. The instrument can be operated
as usual , but results may be erroneous. To restore
accuracy, recalibrate, as described in paragraph 5.9.
222 4 XXXX. Range 4 may be incorrectly calibrated.
Refer to paragraph 5.9 for recalibration procedure. If
calibration is accomplished correctly, but this failure
display appears when POWER is cycled OFF and
ON, the calibration data is stored in the "Dallas Chip"
(U36) which should be replaced.
2223 XXXX. Range 3. Be sure that recalibration has
been done correctly.
222 2 XXXX. Range 2. Same comment as for range 3.
222 1 XXXX. Range 1. Same comment as for range 3.
222 0 XXXX. Frequency correction factor.
ANALYSIS PROCEDURE: Refer to 444 E XXXX.
11111 1111. Math chip operational check failure.
COMMENT: This test is performed only if you have
the high-speed interface option 1689-9620 installed.
NOTE: This is a non-catastrophic failure. If you press
the [C/D] key, the Digibridge can be operated as usual,
but measurement time will be typical of an instrument
WITHOUT the high-speed option.
Service and Maintenance