8. MAINTENANCE
8.1 Fault finding during commissioning
If a BA558E fails to function during commissioning
the following procedure should be followed:
Symptom
Cause
Check
No display
Incorrect
wiring
There should be up
to1.2V between
terminals 1 & 3 with
terminal 1 positive, or up
to 5V with terminal 12
positive if optional
backlight is loop
powered.
No display and
no voltage
between
terminals
1 & 3 or 12 &
3 if optional
backlight is
loop powered.
Incorrect
wiring or no
power supply.
Check wiring and
confirm that a 4/20mA
current is flowing in the
loop.
Rate display
showing
-99999 or
99999 with all
decimal points
flashing
Over-range
The rate display has
been incorrectly
calibrated & is trying to
display a number
outside the range
–99999 to 99999.
Recalibrate rate display.
Total display
showing
-9999999 or
99999999 with
all decimal
points flashing
Over-range
Reset total display to
zero.
Unstable rate
display
4/20mA
current has a
large ripple
content
Eliminate source of
electrical noise .
Reduce resolution of the
rate display to mask flow
noise
Unable to
access
configuration
menu
Incorrect
security code
Enter the correct
security code
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 BA558E fails after it has been functioning
correctly, the following table may help to identify
the cause of the failure.
Symptom
Cause
Check
No display and
no voltage
between
terminals
1 & 3 or 12 &
3 if optional
backlight is
loop powered.
No power
supply.
Confirm that a 4/20mA
current is flowing in the
loop.
Unstable rate
display
4/20mA
current is
noisy or the
flow signal is
unstable
Eliminate source of
electrical noise .
Reduce resolution of the
rate display to mask flow
noise
Unable to
access
configuration
menu
Incorrect
security code
Enter the correct
security code
Rate display
showing
99999 with all
decimal points
flashing
Over-range
The rate display has
been incorrectly
calibrated & is trying to
display a number greater
than 99999.
Total display
showing
99999999 with
all decimal
points flashing
Over-range
The total display has
been incorrectly
calibrated & is trying to
display a number greater
than 99999999.
If this procedure does not reveal the cause of the
fault, it is recommended that the instrument is
replaced.
8.3 Servicing
All BA558E loop powered Rate Totalisers are
interchangeable if the required optional backlight
and alarms are fitted. A single spare instrument
may quickly be recalibrated to replace any
instrument that is damaged or fails. No attempt
should be made to repair instruments at
component level.
We recommend that faulty instruments
are returned to BEKA associates or to
your local BEKA agent 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.
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