Troubleshooting Guide
Component Check
SKF Multilog On
-Line System IMx-M
6 - 5
User Manual
10. Disconnect the connector from the sensor and short circuit the pins in the sensor
contact, then remeasure the voltage on the IMx-M terminal block. Did the voltage
sink to close to zero (<0.5 V)?
YES: There is an internal break in the sensor, or the contact is oxidized. First, try
cleaning the contact before replacing the sensor.
NO: There is a break in the cable. Repair the cabling.
Checking sensor and sensor cabling for analog channels
1. Determine the rack number and channel number of the channel in question
through the measurement point information in the software, or through the list of
terminal blocks.
2. Measure the DC voltage between the sensor cable poles on the IMx-M terminal
block using a digital voltmeter.
3. Does the terminal block have the expected voltage level (see sensor sensitivity and
the current actual value of the measured object)?
YES: The sensor and cabling are probably OK. If the actual value is still not
perceived to be normal, then the fault is probably in the channel settings, or
there is a hardware fault in the IMx-M rack. Continue below.
NO: Continu
e to step 5.
4. Check through the current settings for the channel in question in the software.
Determine the amplification, zero level, and the conversion to the user’s rack.
Furthermore, the cable check must be OFF (N). If this still does not produce the
correct actual value, then the input card is probably damaged. Contact SKF
Condition Monitoring Center Luleå.
5. The cable or the sensor is probably damaged. Test the cabling by disconnecting at
the sensor end and connecting e.g. a 1.5 V battery. Does the input now measure
the voltage?
YES: The sensor is probably not functioning correctly. However, first check that the
channel is correctly configured according to the terminating resistor. In the list
of terminal blocks, it can be determined whether the channel in question has
a terminating resistor for current circuit. Check that this corresponds in
reality, and that it corresponds to the sensor’s mode of operation.
NO: The cabling is probably damaged. Continue to step 6.
6. Cable is probably damaged. However, first try disconnecting one of the poles on the
cable from the IMx-
M terminal block. If the voltage is OK, then the fault is in the
IMx-
M rack input stage. Otherwise, the cable is damaged and needs to be repaired.
7. Does the fault remain after replacing the sensor?
YES: The fault can be in the analog input part of the IMx-M rack. Contact SKF
Condition Monitoring Center Luleå.
NO: It is a sensor fault. The sensor is defective and must be replaced.