4 recurring function test – VEGA VEGAVIB 65 - NAMUR User Manual
Page 21
Note:
The mode adjustment on the NAMUR amplifier must be
selected in such a way that the switching output goes to safe
position in case of a failure message (I <=1 mA).
Level
Signal current -
Sensor
Control lamp
Falling characteris-
tics max.
>=2.2 mA
Falling characteris-
tics max.
<= 1 mA
Rising characteris-
tics min.
>=2.2 mA
Rising characteris-
tics min.
<= 1 mA
Failure
any
<= 1 mA
flashes
6.4 Recurring function test
According to IEC 61508.
VEGAVIB 65 is qualified in mode A (overfill protection) for use
in measuring chains of stage SIL2 according to IEC 61508
(redundant, stage SIL3).
The following instrument combinations meet the requirements
according to SIL:
VEGAVIB 65
l
Oscillator VBE60N
The recurring test according to IEC 61508 can be carried out
by pushing the simulation key on the oscillator or by briefly (>2
seconds) interrupting the cable to the sensor. The correct
SIL
Recurring function test
VEGAVIB 65 - with NAMUR output
21
Set up
31218
-EN
-060508