3 failure rectification – VEGA VEGATOR 622 User Manual

Page 18

VEGATOR 620 … 622

5.3 Failure rectification

Failure

Rectification / Measure

Instrument is dead/
Green operating
lamp extinguishes

Check the voltage supply and the mains connections as described
under „Connection instructions“. If the instrument still does not function,
please call our service department.

VEGATOR 620

Check the sensor inputs for the following failures:

functions incorrectly

- short-circuit on the input

or not at all

- sensor not connected correctly or polarity-reversed
- sensor line interrupted
- supply voltage too low

Red failure LED
of VEGATOR 621

Check if the sensor is connected correctly.

or 622 lights

- failures in the sensor, effecting a current change to below 2 mA or

above 23 mA, generate a fault signal on VEGATOR.

Measure the current in
the connection cable
to the sensor.

For Ex systems, make sure that the Ex protection is not degraded
by the measuring instruments.

a. Current value < 2 mA

- Check the supply voltage on the connection cable to the sensor. The

voltage should be at least 17 V.
Should a value below 17 V be measured, it indicates a defect in the
signal conditioning instrument. In this case, return the instrument for
repair to VEGA.

- If at least 17 V are available, separate the signal conditioning instru-

ment from the connection cable and connect to the sensor input of
the signal conditioning instrument a resistor of 2.2 kOhm.
If the failure lamp continues to light, the signal conditioning instrument
is defective. In such a case, return the instrument for repair to VEGA.

- Should the failure lamp extinguish, reconnect the signal conditioning

instrument. Separate the sensor from the connection cable and con-
nect a resistor of 2.2 kOhm in its place.

- Should the failure lamp continue to light, there is probably an inter-

ruption of the connection line. Check the connection cable to the
sensor.

- If the failure lamp extinguishes, the sensor is defective. Check the

connected sensor.

Diagnostics

VEGATOR

1 2

15 … 18 V
(24 V with VEGATOR 620)

4 … 20 mA