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4.9 MAINTENANCE
4.9.1 Fault finding during commissioning
If a BA364D tachometer fails to function during
commissioning the following procedure should be
followed:
Symptom
Cause
Check:
No display
Incorrect
wiring
Note:
Terminals 2, 4
& 8 are
interconnected
within the
BA364D
That there is
between 10 and
28V on terminals
1 & 2 with terminal
1 positive.
Speed display
always zero
Incorrect
programming
or input wiring
That instrument
has been
programmed for
the transducer in
use, and that it is
connected to
terminals 3 & 4
with terminal 3
positive.
No run-time
display
Run-time
display not
switched on.
Programming
see 4.5.5
Run-time
display
always zero
Clip-off
incorrectly set.
Reset
terminals
connected
together
Programming
see 4.5.9
Wiring & reset
switch.
Unable to
enter
programme
mode
Incorrect
security code
That correct
security code is
being used, or fit
security link in
override position.
See Fig 1.4
4.9.2 Fault finding after commissioning
ENSURE PLANT SAFETY BEFORE
STARTING MAINTENANCE
Live maintenance is permitted on
intrinsically safe equipment installed in a
hazardous area, but only certified test
equipment should be used unless a gas
clearance certificate is available.
If a BA364D tachometer fails after it has been
functioning correctly, the following table may help
to identify the cause of the failure.
Symptom
Cause
Check:
No display
No power
supply.
That there is
between 10 and
28V on terminals
1 & 2.
Speed display
always zero
Transducer or
associated
wiring has been
damaged.
Presence of
pulse signal
between input
terminals 3 & 4.
Run-time
display not
functioning
Remote reset
contact closed
That remote
reset contact is
not closed or
associated
wiring damaged.
Colon appears
between digits
in display
Display has
overranged
Calibration and
change to
reduce size of
display
If this procedure does not reveal the cause of the
fault, it is recommended that the instrument is
returned to BEKA or to our agent in your area for
repair.
