5 diagnosis, 1 maintenance, 2 failure removal – VEGA VEGABAR 21 User Manual

Page 23: Fault signals, Fault finding

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VEGABAR 21

23

Diagnosis

5 Diagnosis

5.1 Maintenance

VEGABAR process pressure transmitters are
maintenance free.

5.2 Failure removal

Fault signals

With selftest and continuous self-monitoring
VEGABAR offers high reliability. If however
interferences occur, the diagnosis of VEGA-
BAR distinguishes between atypical process
conditions and faults in the VEGABAR.

Atypical process conditions

Exceeding or decreasing of the measuring
range limits (fault signal extinguishes when
the value is again in the measuring range).

Failure in VEGABAR

Failure in the electronics, interferences or
damages in the measuring cell.

The below table assists in the processing of
fault signals.

Reason

Fault signal via

DOT-matrix

Bargraph

Current

Digital indication

output

Clear de-

“OPERATE

Bargraph 0 %

creasing or

????

or 100 %

Current

exceeding

bar“

Digital value

value

of the

flashes

3,6 mA

measuring

or

range

22 mA

Overload

Bargraph 0 %

range of the

or 100 %, digital

measuring

value: four flashing

cell

segments “- - - -”

Failure in

all segments

VEGABAR

flash

On instruments with menu-guided adjustment
with additional functions, possible reasons
are displayed in the menu point “Diagnosis
no.“ in case of failure.

Diagnosis no.

Meaning

1

No frequency from C/f-converter

2

Frequency signal of the capacitor
outside the limit values

3

Frequency signal of the reference
capacitor outside the limit values

4

Frequency signal temperature outside
the limit values

7

Communication to EEPROM interfered

9

Error in CRC-check sum EEPROM

Fault finding

If the indicated value does not correspond to
the level in the vessel or to the process pres-
sure, the following measures have to be
carried out:
- check the pressure compensation (only

with overpressure measuring ranges)

- check the electrical connection.

Checking pressure compensation

Open the housing of VEGABAR. The meas-
ured value should not change. However if the
indicated value changes, compensation of
the atmospheric pressure is not ensured and
the measured value will be affected. Check
the breather facility on the VEGABAR-hous-
ing.

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