Measures, Failure Removal - Vega EL 11 Operating Instructions Manual

Failure
Sensor defect,
measurement does
not react to level
changes
46

Measures, failure removal

Test of the internal connections:
• Loosen the 4 screws of the housing cover with a screwdriver and
remove the housing cover.
• Loosen the two small screws with a screwdriver and pull the oscillator
out of the housing.
• Measure with an Ohm-Meter (range MΩ) the resistance values
between the following contacts:
Screen
C - Meas. capacitor
M
Contact 4 against middle pin (1)
The resistor must be 1 MΩ .
If the resistor is less, this means humidity in the housig or a failure in the
electrode isolation. A possible reason could be a not isolated electrode
which is used in conductive (humid) product.
If the resistor is higher or if the connection is interrupted, the reason is
mainly a bonding failure in the adapter plate or a defect resistor due to
strong electrostatic discharge.
In both cases the electrode must be repaired at VEGA.
6
C
M
4
1 M
Capacitive electrodes EL 4 ... 20 mA - compact
Diagnosis