18
The analogue bargraph will be
automatically calibrated to display 0
with 4mA input and full scale with
20mA input.
Step 7
Return to display mode
Following completion of calibration
return to the display mode by
pressing
'E
'.
8.
MAINTENANCE
8.1
Fault finding during commissioning
If
a
BA326C
fails
to
function
during
commissioning the following procedure should
be followed:
Symptom Cause Solution
No display
Incorrect
There should be 1.1V
wiring
between terminals 1
& 3 with terminal 1
positive.
No display
Incorrect
Check that a current
and no volts
wiring or
is flowing in the
between
no power
loop.
terminals
supply.
1 and 3.
Insufficient
Check supply
loop voltage
voltage and voltage
to operate
drops caused by all
indicator
components in the
loop
Indicator
Positive
The indicator has
displays 1
over-range
been incorrectly
calibrated & is trying
to display a number
greater than 19999,
or input current is
greater than
approximately
21mA.
Indicator
Negative
The indicator has
displays -1
0ver-range
been incorrectly
calibrated & is trying
to display a number
less than -19999, or
the input current is
less than
approximately
3.5mA.
Unstable
4/20mA
Check loop supply
display
input has a
voltage.
large ripple
content.
Unable to
Incorrect
Enter correct
enter the
security
security code or fit
programme
code
security link in
mode
entered.
override position.
See Fig 9.
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 BA326C fails after it has been functioning
correctly, the following procedure should be
followed:
Symptom Cause Solution
No display
No power
Check that a
and no volts
supply
current is flowing in
between
the loop.
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.
8.3
Servicing
All
standard
BA326C
indicators
are
interchangeable, and a single spare may be
used to replace any instrument which fails.
We recommend that faulty instruments are
returned to BEKA associates or to our local
agent for repair.
Summary of Contents for ba326c
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