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7. MAINTENANCE
7.1 Fault finding during commissioning
If the BA304ND fails to function during
commissioning the following procedure should be
followed:
Symptom
Cause
Solution
No display
Incorrect
There should be 1V
wiring.
between terminals 1 &
3 with terminal 1
positive.
(5V between terminals
1 & 13 if a loop
powered backlight
is fitted).
No display
Incorrect
Check that a current
and no volts
wiring or
is flowing in the loop.
between
no power
terminals 1
supply.
and 3.
Insufficient Check supply voltage
loop
and voltage drops
voltage to
caused by all
operate
components in the loop.
BA304ND.
BA304ND
Positive
The BA304ND has
displays 1
over-range. been incorrectly
calibrated & is trying to
display a number
greater than 1999.
BA304ND
Negative
The BA304ND has
displays -1
over-range. been incorrectly
calibrated & is trying to
display a number
less than -1999.
Unstable
4/20mA
Check loop supply
display
input has a voltage.
large ripple.
7.2 Fault finding after commissioning
CAUTION!
ENSURE PLANT SAFETY BEFORE
STARTING MAINTENANCE
Live maintenance should only be
performed when there is no risk of a
flammable atmosphere being present,
and dust or water can not enter the
enclosure. Before replacing control &
terminal covers ensure that the sealing
gaskets are undamaged and free from
dirt and foreign bodies.
If a BA304ND 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
between
loop.
terminals 1
and 3.
Unstable
4/20mA
Check loop supply
display.
input has a
voltage.
large ripple.
If this procedure does not reveal the cause of the
fault, it is recommended that the instrument is
replaced.
7.3 Servicing
CAUTION!
ENSURE PLANT SAFETY BEFORE
STARTING MAINTENANCE
Live maintenance should only be
performed when there is no risk of a
flammable atmosphere being present,
and dust or water can not enter the
enclosure. Before replacing control &
terminal covers ensure that the sealing
gaskets are undamaged and free from
dirt and foreign bodies.
We recommend that faulty instruments and
instrument assemblies are returned to BEKA
associates or to your 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.
