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8. MAINTENANCE
8.1 Fault finding during commissioning
If a BA344D fails to function during
commissioning the following procedure should
be followed:
Symptom
Cause
Check:
No display
Instrument has
not been
switched ON.
Battery is not
conditioned.
Position of slide
switch above
terminals 3 & 4.
See Figs. 5 & 6.
See Appendix 2
Flow indicator
not rotating
No input
pulses,
incorrect input
terminals
used, or
incorrect type
of input
selected
That BA344D has
been calibrated for
the correct input.
That input signal is
connected to
correct input
terminals and
correctly polarised.
Flow indicator
rotating but
incorrect rate
display
Incorrect
calibration
Input below
clip-off
threshold
That rate scale
factor and
timebase are
correctly
programmed.
That clip-off
threshold is set
correctly.
Unstable rate
display
Noisy pulse
input signal
Source of noise
and try to
eliminate, or
increase rate filter.
Correct rate
display but
incorrect total
display
Incorrect
calibration
Remote reset
switch
contacts
closed
That total scale
factor is correctly
programmed.
That ‘RESET’
annunciator is not
activated. If it is,
check reset wiring
and switch.
Unable to
enter
programme
mode
Incorrect
security code
That the correct
security code is
being used, or fit
security link in
override position.
See Fig 10.
8.2 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 BA344D fails after it has been functioning
correctly, the following table may help.
Symptom
Cause
Check:
No display
Instrument has
been switched
OFF
If BA344D has
been switched
off for an
extensive
period battery
may need
conditioning.
Discharged
battery
Position of slide
switch above
terminals 3 & 4.
See Figs. 5 & 6.
See Appendix 2
If replacement
battery restores
operation
Low battery
annunciator
activated
Battery almost
exhausted.
Install
replacement
battery as
soon as
possible.
Instrument
displaying
‘bAtt’
Battery
exhausted.
Install
replacement.
Flow indicator
not rotating
No input
pulses
Output from
flowmeter and
wiring between
flowmeter and
BA344D.
Flow indicator
rotating,
‘HOLD’
annunciator
activated.
Input below
clip-off
threshold
Clip-off threshold
and if necessary
adjust.
Unstable rate
display
Noisy pulse
input signal
Source of noise
and try to
eliminate, or
increase rate filter.
If this procedure does not reveal the cause of
the fault, it is recommended that the instrument
is replaced.
8.3 Servicing
We recommend that faulty BA344D rate
totalisers are returned to BEKA associates or
to our local agent in your area for repair.
8.4 Routine maintenance
The mechanical condition of the instrument
and electrical calibration should be regularly
checked. The interval between inspections
depends upon environmental conditions. We
recommend that initially instrument calibration
should be checked annually.
8.5 Guarantee
Instruments which fail within the guarantee
period should be returned to BEKA associates
or our local agent. It is helpful if a brief
description of the fault symptoms is provided.
Summary of Contents for BA344D
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