VEGA MINITRAC 31 4 … 20 mA_HART - four-wire - Manual (Page 70)

70
9 Diagnostics and service
MINITRAC 31 • 4 … 20 mA/HART - four-wire
40447-EN-131119
Error Cause Rectification
4 … 20 mA signal
missing
Electrical connec-
tion faulty
Check connection according to
chapter "Connection steps" and if
necessary, correct according to chap-
ter "Wiring plan"
Voltage supply
missing
Check cables for breaks; repair if nec-
essary
Operating voltage
too low or load re-
sistance too high
Check, adapt if necessary
Current sig-
nal greater than
22 mA or less
than 3.6 mA
Instrument on fail-
ure message
Note error message on the display
and adjustment module
The following table describes possible faults that may not generate an
error message:
Error Cause Rectification
The instrument
signals covered
without covering
with the medium
The instrument
signals covered
with covering with
the medium
Voltage supply
missing
Check cables for breaks; repair if nec-
essary
Operating voltage
too low or load re-
sistance too high
Check, adapt if necessary
Electrical connec-
tion faulty
Check connection according to
chapter "Connection steps" and if
necessary, correct according to chap-
ter "Wiring plan"
Electronics de-
fective
Change the switching behaviour of the
sensors under "Diagnosis/Simulation".
If the instrument does not switch over,
send it in for repair.
Buildup on the in-
ner wall of the
vessel
Remove buildup
Check the Delta I value.
Improve the switching threshold - car-
ry out a double point adjustment
Current sig-
nal greater than
22 mA or less
than 3.6 mA
Electronics mod-
ule in the sensor
defective
Note error messages on the display
and adjustment module
Depending on the reason for the fault and the measures taken, the
steps described in chapter "Setup" must be carried out again or must
be checked for plausibility and completeness.
Should these measures not be successful, please call in urgent cases
the VEGA service hotline under the phone no. +49 1805 858550.
The hotline is also available outside normal working hours, seven
days a week around the clock.
Check output signal
(level detection)
Reaction after fault recti-
fication
24 hour service hotline