Each of these faults will also be visible in the time waveform as an erratic jumping or spiking of the signal. Thermal transient signals cause thermal expansion of the sensor housing materials. This is detected by the sensor as a low frequency signal. The problem is most evident when using low frequency sensors. One way to reduce the effects of thermal transients is to cover the sensor with a thermal boot.
Thermal boots are available from most sensor manufacturers.
Poor or contaminated connections can also cause low frequency bias and contact noise. Look for corroded, dirty or loose connections. Repair or replace the connection as necessary. Non-conducting silicone grease should always be applied to connectors to reduce contamination. Ground Loops are developed when the cable shield is grounded at two points of differing potential.