Bitronics QTWIE2, Руководство пользователя

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ML0030 August 2009 Copyright 2009 Bitronics, LLC
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TABLE I - SELF TEST RESULT SUMMARY FOR 3-PHASE WATT/VAR METERS
Fault
1. Display Overflow
2. CT/PT ratio checksum
error
3. CT/PT board calibration
checksum error
4. Analog board calibration
checksum error
5. Watchdog timer timeout
Fault Indication
Display f1999 or
-1999.
Top display alternately
displays 3 dashes (---) and
fault code 1 (--1). On
QTWIE2 bottom display
displays 3 dashes (---).
Top display alternately
displays reading and fault
code 2 (--2).
Top display alternately
displays reading and fault
code 3 (--3).
Both displays alternately
display readings and
blanks.
Effects of Fault
Measured quantity is too large to be
displayed. Transducer output may still be
accurate, if overload does not exceed
transducer output ratings.
Scaling of the display cannot occur due to
the loss of the CT and/or PT ratios. The
transducer outputs are still functional and
accurate.
Calibration constants for the CT/PT Board
are in error. The display and the
transducer output are reduced in accuracy
to approxi/-3%.
Calibration constants for the Analog
Processing Board are in error. The display
and the transducer output are reduced in
accuracy to approxi/-3%.
The watchdog timer is attempting to reset
the microcontroller due to low supply
voltage, or a fault in the microcontroller.
Displayed values and transducer output are
inaccurate.
Corrective Action
Correct fault external to
instrument.
Attempt to reset the CT&PT
ratios. If Fault continues,
replace Power Supply Board
and recalibrate the instrument,
or replace the Base Module.
Replace Power Supply Board
and recalibrate the instrument,
or replace the Base Module.
Replace Analog Processing
Board or the Electronics
Module.
Check input supply voltage to
verify it is within specifications.
If supply is OK, replace
Microcontroller Board, or
replace Electronics Module.