© Brüel & Kjaer Vibro GmbH/4 mm ds821 / 21.7.15 /technical specifications subject to change / C104958.001/V02
l
28
EN
5.2
Troubleshooting
Check the output signal
a.
The output signal U
SIG
< -18 V. The distance between target and sensor tip lies outside the
measuring range. Adjust the sensor so that it is nearer the target.
b.
The output signal U
SIG
> -2 V.
Possibly the distance between target and sensor tip is too small. Adjust the sensor to
increase the distance to the target and re-check U
SIG
. If the output signal does not change,
the displacement sensor system is defective. Follow these additional steps.
Check the displacement sensor and the extension cable:
a.
Measure the supply voltage I
B
(terminal 2) with extension cable and displacement sensor
connected. Disconnect the cable connected to the driver (terminal 1) and measure supply
voltage I
B
again. If I
B
changes by about 1.4 mA, the sensor cable and the displacement
sensor are OK. Otherwise, there is a disruption in the displacement sensor or extension
cable.
b.
Check the resistance of the extension cable and the displacement sensor:
For a 5 m system: R
sensor
+ R
ext.
= 9.6 Ω
±
0.3 Ω
For a 10 m system: R
sensor
+ R
ext.
= 13.6 Ω
±
0.3 Ω
Otherwise the displacement sensor or extension cable is defective.
Check the driver:
Measure the voltage (terminal 2) at the driver without the displacement sensor connected
and without cables. The result you should obtain is
I
B
= 8,7 mA +-1 mA . Otherwise, the
driver is defective.
