BEKA BA358E, Руководство пользователя

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9. MAINTENANCE
9.1 Fault finding during commissioning
If a BA358E fails to function during commissioning
the following procedure should be followed:
Symptom Cause Check
No display Incorrect
wiring Check wiring
There should be 0.6
to 1.2V between
terminals 1 & 3 with
terminal 1 positive.
With an optional
backlight, loop
powered, there
should be 3.4 to 5V
between terminals 3
& 12 with terminal 12
positive.
No display
0V between
terminals 1 &
3. Incorrect
wiring or no
power supply Check supply
voltage and voltage
drop caused by all
the instruments 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
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 BA358E 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
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.
9.3 Servicing
All BA358E 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.
9.4 Routine maintenance
Routine maintenance should comply with the
recommendations contained in BS EN 6007-17
‘Electrical Installations Inspections and
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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