Vega VEGACAL 69 Operating Instructions Manual page 44

9 Maintenance and fault rectification
Error
4 ... 20 mA signal missing
Current signal greater than
22 mA or less than 3.6 mA
Check the resistance in
the probe
44
Cause
Wrong connection
Voltage supply missing
Operating voltage too low
or load resistance too high
Shortcircuit in the probe,
e.g. because of moisture in
the housing
Sensor electronics de-
fective
Remove the electronics module. Check the resistance between the
two plug connections.
There must no longer be a connection (high impedance). If there is
still a connection, exchange the instrument or return it for repair
Fig. 28: Check the resistance in the probe
1 Shielding
2 Measuring probe
3 Ground potential
In Ex applications, the regulations for the wiring of intrinsically safe
circuits must be observed.
Rectification
Check connection according to chapter " Connection
steps" and if necessary, correct according to chapter "
Wiring plan"
Check cables for breaks; repair if necessary
Check, adapt if necessary
Remove the electronics module. Check the resistance
between the marked plug connections. See the follow-
ing instructions.
Exchange the instrument or send it in for repair
VEGACAL 69 • Two-wire 4 ... 20 mA/HART
2 1 3