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10. MAINTENANCE
10.1 Fault finding during commissioning
If a BA384NG fails to function during commissioning
the following procedure should be followed:
Symptom
Cause
Check:
No display
No power supply,
or incorrect
wiring.
Note: Terminals 2,
6, 10 & RS2 are
interconnected
within the
instrument.
That there is
between 10 and
30V on terminals
1 & 2 with
terminal 1
positive.
Rate Totaliser is
receiving power
but flow indicator
is not rotating
when either input
is selected.
No input pulses,
or incorrect input
configuration
Input
configuration.
Correct linking of
terminals 3 & 4
for input A and
terminals 7 & 8
for input b.
Input pulses have
correct polarity.
Flow indicator
rotating, but
incorrect rate
display on one or
both inputs.
Incorrect rate
display
calibration.
Factor-A
factor-b
5cale
.
r-A
5cale
.
r-b
t-ba5e
Flow indicator
rotating, but
incorrect total
display.
Incorrect total
display
calibration.
Remote reset
switch contacts
are closed.
Factor-a
factor-b
5cale
.
t-A
5cale
.
t-b
If reset
annunciator is
activated, check
reset wiring and
switch.
Unstable rate
display.
Noisy pulse input
signal.
Eliminate
electrical noise.
Increase input de-
bounce and/or
display filter.
Alarms do not
function.
Alarms have
been
automatically
disabled following
rate display
recalibration.
Enable both
alarm outputs.
Unable to enter
configuration
menu.
Incorrect security
code
That the correct
security code is
being used.
Contact BEKA if
code is lost.
10.2
Fault finding after commissioning
EN 60079-17
Electrical installations inspection and
maintenance
permits live maintenance in Zone 2 if a
risk analysis demonstrates that this does not
introduce an unacceptable risk. The removal of
covers [opening of Ex n instrument enclosure] is
permitted if this can be done without contaminating
the interior of the instrument with dust or moisture.
Some end-users may prefer not to permit live
maintenance to minimise risk.
ENSURE PLANT SAFETY BEFORE
STARTING MAINTENANCE
Live maintenance within the hazardous area
should only be performed when it is
permitted by risk analysis, or when there is
no risk of a flammable atmosphere being
present.
Symptom
Cause
Check:
No display
No power supply
That there is
between 10 and
30V on terminals
1 & 2 with
terminal 1
positive.
Flow indicator not
rotating on one or
both inputs.
No input pulses
Output from
flowmeter.
Wiring between
flowmeters and
BA384NG.
Flow indicator
rotating. HOLD
annunciator
activated.
Input is below
clip-off threshold
Clipoff
threshold and
adjust if
necessary.
Unable to enter
configuration
menu.
Incorrect security
code
That the correct
security code is
being used.
Contact BEKA if
code is lost.
If this procedure does not reveal the cause of the
fault, it is recommended that the instrument is
replaced.
10.3 Servicing
We recommend that faulty BA384NG rate totalisers
are returned to BEKA associates or to your local
BEKA agent for repair.
10.4 Routine maintenance
The mechanical and electrical condition of the
instrument should be regularly checked. Inspection
frequency should be adjusted to suit the
environmental conditions.