Trouble Shooting; Problems With Displacer Movement - Honeywell 854 ATG Series Instruction Manual

6

Trouble shooting

The 854 ATG is an instrument with self diagnostics. Detected errors will be shown as status information on
the display (refer to Appendix D), or can be requested as items by the PET.
The following items contain the error codes of the processor boards:
EP Error XPU(-2) request (communication processor unit)
ES Error SPU request (servo processor unit)
These items contain an error code of the last error condition. The error codes can be read as long as the
gauge is not reset.
Besides the error codes, data items from level and optional functions (such as temperature and analog level
output) contain one or more status bytes which also give valuable information. These bytes are readable
ASCII characters. However, most of them are bit coded. Appendix C contains an ASCII table for conversion
of the status bits into the actual status.
An example for a bit coded status byte:
one (of the) status byte(s) reads:
written out in bits (refer to Appendix C):
(b7=0, b6=1, b5=0, b4=0, b3=0, b2=1, b1=1, b0=0).
Bit 7 is always a '0' and bit 6 is always a '1' to avoid 'control' characters.
Look up the relevant status byte in this section (e.g. QS in section 6.4) to determine the meaning of the bits
which are set to '1'. Only the bits set to '1' represent an actual status.

6.1 Problems with displacer movement

If the displacer is not running freely, for instance stuck against a stilling well, it can be controlled manually.
Note:
Be aware that measuring wire is unrolled from the measuring drum. When the measuring wire is not kept
at tension, the result will be an uncontrolled wire movement which results in the worst case in the lost of
the measuring wire.
Item Name
W2
Protection level 2
SM Set maintenance
GD Go down
FR Freeze
SO Set operational
EX Exit
When hereafter the displacer is free and the weight is too high, the force transducer must be recalibrated.
When the measured displacer weight is too far out of range, the gauge is probably not levelled within 2°.
Then, improve the stability of the construction on which the gauge is mounted.
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F;
0100 0110;
Description
Enter protection level 2 password.
Go into maintenance mode.
Go down for approximately 200 mm (8").
Give the freeze command.
Exit maintenance mode
Exit protection level 2
Trouble shooting