Cleaning of sensors

Cleaning of sensors is important 

Although cleaning of all types of pressure sensors is important, it is particularly important for vacuum sensors, as they are significantly more sensitive to contamination. 

Cleaning is especially important in those cases where the process involves the use of substances that are hazardous, or which can form hazardous substances when in contact with other substances.  In such cases, cleaning is essential in order to ensure the safety of personnel maintaining or calibrating the sensor. 

Dirty sensors can damage your equipment

A sensor must always be clean before it is calibrated. Dirty sensors damage the reference equipment, which can become very expensive. At the same time, it must be realised that cleaning can affect the performance of a sensor, and sometimes even damage it. 

To avoid damaging a sensor while cleaning it, it is important to understand its construction, e.g. the design, arrangement and fitting of membranes, seals, heat sinks  etc. 

Tips if you're doing your own cleaning 

• Start by cleaning visible surfaces with cotton wool buds dipped in alcohol.
• Pour alcohol into the sensor.  Turn it carefully back and forth, but don't shake it.  Leave it to stand for half an hour or so, with the alcohol in it. 
• Empty out the alcohol and fill the sensor with distilled water.  Turn it around a little, and then pour out the water.  Repeat this two or three times.
• Leave the sensor to dry naturally.  It is particularly important that vacuum sensors operating at high voltages (e.g. Penning traps), or sensors with ceramic parts, should be dry before use.  
• Be careful at all times not to leave fingerprints on connection terminals.
• Protect connections with appropriate covers.  Grease can be removed with petroleum distillate or something similar, but remember to do so in a fume cupboard. 

Please contact us if you have any special problems with process contamination, and these notes don't solve the problem.