VEGA VEGAWELL 71 - Manual (Page 10)

10 VEGAWELL 71
Fault finding
If the level does not correspond to the indi-
cated measured value, first of all the pres-
sure compensation, and then the electronics
of the measuring system should be checked.
Checking of the pressure compensation
Open the external connection housing
(VEGABOX 01). The measured value must
not change at, a steady level. If the meas-
ured value changes, the required compensa-
tion of the atmospheric pressure is not
guaranteed (influence of the measured
value!).
In this case, the breather facility in the exter-
nal connection housing and the breather
capillaries must be checked.
Checking of the measuring circuit
In measuring systems with overvoltage ar-
resters, these should first be checked for
interruption or shortcircuit.
Voltage
The supply voltage on the connection of the
pressure transmitter must be 12 … 36 V DC.
Current
Initial current with uncovered diaphragm of
the pressure transmitter: approx. 4 mA.
Meas. current during operation: 4 … 20 mA.
Meas. line interrupted: current = 0 mA.
Exceeding or decreasing of meas. range:
3 … 4 mA (decreasing of meas. range),
20 … 22 mA (exceeding of meas. range).
Pressure transmitter defect or shortcircuit:
current > 23 mA.
V mA
+
–
VEGAWELL 71
to processing
unit and supply
voltage
Set-up