How to choose the right contact cleaner spray?
Contact cleaners dissolve oil, flux and oxide layers on connectors, relays and boards. This guide shows how to choose a contact spray by plastic compatibility, residue behaviour and suitability for live components.
View contact cleanersWhat types of contact cleaner exist?
A contact cleaner is not the same as a contact spray. There are pure cleaners that dry residue-free and protective contact sprays that leave a thin lubricating film. Both serve different jobs and should not be confused.
Pure contact cleaners based on isopropanol or dedicated solvents remove flux, grease and moisture and evaporate completely. Protective sprays also contain oils or corrosion inhibitors and are used on moving contacts such as switches, potentiometers and connectors.
- Contact cleaner (residue-free): final cleaning of boards and precision contacts.
- Contact spray with care film: protection and smooth action of switches and relays.
- Oxide remover: dissolving hard oxide and sulphide layers on aged contacts.
- Compressed air/freezer spray: blowing out dust mechanically without solvents.
Which criteria decide the right spray?
Three properties decide: plastic compatibility, residue behaviour and suitability for live components. Each criterion relates to the actual part you need to clean.
Cleaning live components - what is allowed?
Some contact sprays are released for use on energised equipment and show a high dielectric strength, often more than 30 kV. Even so, the rule stands: wherever possible, de-energise the equipment before cleaning.
- Isolate the equipment and secure it against re-energising where possible.
- Use only sprays with a stated dielectric strength.
- Ensure good ventilation - many cleaners are flammable.
- Let the cleaner flash off completely before switching back on.
Residue-free performance matters twice as much on live contacts: an oil film can raise contact resistance at low signal voltages, while cleaner residue can creep inside connectors and encourage short circuits.
Frequently asked questions
What is the difference between a contact cleaner and a contact spray?
A contact cleaner dries residue-free and is meant for pure cleaning. A contact spray leaves a thin care and protection film and is used on moving contacts such as switches and potentiometers.
Is contact spray safe on all plastics?
No. Aggressive solvents can attack ABS, polycarbonate or PVC. On plastic housings use only cleaners with an explicit plastic release from the maker and test on an inconspicuous spot first.
Can you spray on live components?
Only with cleaners that state a high dielectric strength. It is safer to de-energise the equipment first and let the cleaner flash off completely before re-energising.
Why does residue-free matter so much?
Residue can trap dust, raise contact resistance or creep into connectors. On precision and signal contacts the cleaner should evaporate completely.
Looking for the right contact cleaner?
We stock residue-free contact cleaners and protective contact sprays - plastic-compatible and with high dielectric strength.
Residue-free
Precision cleaners evaporate completely.
Plastic-tested
Releases for common plastics documented.
High dielectric strength
Sprays suited to electronics work.
Expert advice
Our specialists help you choose.