BEKA BA524D, Manual

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7.2 Fault finding after commissioning
ENSURE PLANT SAFETY BEFORE
STARTING MAINTENANCE
If a BA524D fails after it has been functioning
correctly, the following table may help to identify
the cause of the failure.
Symptom Cause Solution
No display No power Check that a current
and no volts supply is flowing in the loop.
between
terminals
1 and 3.
Unstable 4/20mA input Check loop supply
display has a large voltage.
ripple.
Incorrect Digital filter Recalibrate
calibration FrE has been
changed after
indicator was
calibrated.
If this procedure does not reveal the cause of the
fault, it is recommended that the instrument is
replaced. This can be done without disconnecting
power, but while the indicator is disconnected the
4/20mA loop will be open circuit. Alternatively the
electronic assembly may be exchanged as
described in section 7.3
7.3 Servicing
To simplify servicing all BA524D indicators use a
common display assembly which can be easily
replaced on site. Depending upon the accessories
fitted, one spare display assembly may be used to
repair any BA524D which fails. The exchange may
be made without disconnecting power, the 4/20mA
loop will continue to function but the indicator
voltage drop will increase from 1V to 4V without
the display assembly.
To exchange the display assembly remove the
terminal cover by unscrewing the two 'A' screws
which will reveal two concealed 'D' screws. If the
instrument is fitted with external push-buttons also
unscrew the two 'C' screws securing the buttons
and un-plug the five way connector. Finally
unscrew all four 'D' screws identified in Fig 4 and
carefully lift off the front of the instrument. The
instrument assembly is secured by three Pozi
headed screws which should be removed.
If the instrument is fitted with a backlight or alarms
the fly-leads connecting the accessory boards to
the terminals should be un-plugged. The replace-
ment display assembly may then be installed and
the enclosure reassembled.
If after replacement of the display assembly the
instrument still does not function, it is likely that the
fault is within the protection components on the
terminal assembly. Terminal assemblies may be
exchanged on site providing the replacement
assembly includes terminals for any accessories
fitted i.e. backlight and alarms.
We recommend that faulty instruments and instru-
ment assemblies are returned to BEKA associates
or to our local agent for repair.
7.4 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.
7.5 Guarantee
Indicators 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.
7.6 Customer comments
BEKA associates is always pleased to receive
comments from customers about our products and
services. All communications are acknowledged
and whenever possible, suggestions are
implemented.
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