Instructions for Use SS 20.261
Page 16
Eliminating malfunctions
The following table lists possible errors (error images). A description of
the way to detect errors is given. Furthermore, the possible causes and
measures to be taken to eliminate errors are listed.
Error image
Possible causes
Troubleshooting
Problems with supply voltage U
B
:
No U
B
available
U
B
has wrong polarity
U
B
< 15 V
Sensor defective
Sensor cable connected
correctly?
Supply voltage connected to
the control?
Supply cable broken?
Power supply unit large
enough?
I
wN
, I
TM
= 0 mA
Sensor element defective
Send the sensor for repair
I
wN
, I
TM
= 2 mA
Operating voltage too high
Medium temperature beyond
specification range
Check the operating voltage and
reduce it
Check the medium temperature
and set it correctly
I
wN
= 2 mA
I
TM
= 2 / 22 mA
Flow signal w
N
is
too large / small
Measuring range too small /large
Medium to be measured does not
correspond to air
Sensor element soiled
Sensor installed in opposite
direction to flow direction
Check sensor configuration
Check measuring resistance
Is the foreign gas factor correct?
Clean sensor tip
Check the installation direction
Flow signal w
N
is
fluctuating
U
B
unstable
Mounting conditions:
Sensor head is not in optimal
position
Run-in/run-out distance is too
short
Strong fluctuations of pressure or
temperature
Check the voltage supply
Check mounting conditions
Check operating parameters
Table 6
