EA Technology UltraTEV Plus2 Operating Manual page 71

2388-MANUL-V13.04.00-UltraTEV Plus² Operating Manual
UCP1
The following images present some examples of how unwanted signals may be introduced during the PD
detection process when using the Ultrasonic Contact Probe. These can be categorised as sources of noise and
sources of phantom PD signals. The difference between the two is that noise decreases our detection
capabilities by masking the PD signal, whereas phantom signals may be confused as a PD source.
The first image shows that when the Ultrasonic Contact Probe is kept in the hand during measurements, even
tiny movements of the hand can introduce significant noise to measurements through surface noise. In cases
where it is necessary to hold the Ultrasonic Contact Probe during measurements (e.g. pushing the sensor to
obtain more signal or non-magnetic asset enclosure), a coupling fluid may help to reduce this type of noise.
Any vibrations of the asset surface caused for example by rain in outdoor assets or vibration of transformers
may cause phantom signals. In such cases the audible signal may be appear exactly the same as a genuine PD
source.
UCP1
Shaking the UCP1,
e.g. when held in
the hand
A rough or uneven surface will drastically decrease the amount of
signal being transferred to the sensor head.
Dust ingress between the UCP1 sensor head and the asset surface.
UCP1
Rain in outdoor
assets
UCP1
Vibration (including
transformers) of
asset enclosure
where the UCP1 is
attached
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