INSTALLATION AND OPERATING INSTRUCTIONS
Troubleshooting
SKF Multilog On-line System IMx-16Plus
User Manual
Revision Letter A
39 (66)
In addition to (most of) the above, where the sensor generates a higher than
expected or widely varying signal, consider also the following possible causes:
•
Incorrectly mounted or loose sensor
•
Signal disturbance due to external noise (for example RFI)
•
A grounding issue
Deeper troubleshooting requires the use of suitable test equipment, minimum being a
digital multimeter (DMM).
2.9.3.1 Checking vibration channels
The following flow steps can generally be used to troubleshoot a vibration sensor that
is non-responsive. It is based on checking for the presence of a Bias Output Voltage
(BOV) in an acceptable or expected range.
1. Identify the input terminals where the channel in question is connected to the
IMx-16Plus and measure the DC voltage between the sensor wires at the
terminal block using a digital voltmeter.
2. Is the measured voltage within the expected normal working range? (For a
typical accelerometer this would be 8 to 12 V DC).
NO: Skip to step
YES: The cabling to the sensor is probably OK and the sensor interface to
the IMx-16Plus is normal. If the sensor output signal is still perceived as
incorrect, then check the transducer mounting and try substituting the sensor.
a. Did the fault remain after checking the mounting and changing the
sensor?
NO: If substituting the sensor cleared the fault then the sensor was
defective and should be replaced.
YES: The fault may be in the analogue input section of the IMx-
16Plus device. Contact TSG for advice and further information.
When using test equipment to m
easure within ‘electronic control circuits’
such as sensor wiring, be aware that even ‘simple’ equipment such as a DMM
measuring DCV can in some circumstances significantly alter the circuit
behaviour. Be particularly cautious of using instruments that hav
e a ‘low
impedance measurement function to simultaneously test for voltage or continuity’
and ensure the DCV measurement is being made in a high impedance mode.
