Speed Measurement System; Table 26 Malfunctions Of The Speed - ABB HT564586 Operation Manual

Operation Manual / 4 Product description / A100-L
7 Troubleshooting
7.5

Speed measurement system

Possible causes
No signal or Fitting error
amplitude is
poor
Defective sensor
Measured Contaminated
speeds too sensor tip
high
Measured - -
speed too
low
Other - -
sources of
errors
Table 26: Malfunctions of the speed measurement system
© Copyright 2016 ABB. All rights reserved.
Elimination
The screw plug for the sensor is fitted with a gasket.
When fitting the speed sensor, this gasket must be removed. If the
gasket is fitted by mistake, the distance from the sensor tip to the
signal-generating sealing disc increases. As a result, the voltage
amplitude of the speed signal decreases, which can cause problems
for the evaluation electronics.
This problem is eliminated by removing the gasket.
Contact an ABB Turbocharging Service Station
The sensor tip is magnetic and can thus attract metal particles. As a
result, the distance to the auxiliary bearing decreases, which can
lead to amplification of the noise component and consequently to
faulty triggering.
Remove the sensor, clean its tip and refit the sensor using the spec-
ified tightening torque.
Contact an ABB Turbocharging Service Station
If none of the above measures eliminates the malfunction, we rec-
ommend that you have the speed measuring system inspected by
an ABB Turbocharging Service Station.
HZTL4034_EN
Page 56 / 111
Revision F June 2016