Electrical contacts are often manufactured from relatively soft materials, which are subject to wear. The contact surfaces also oxidise which increases the electrical resistance.
It is specially formulated to give low carbon forming tendencies and to lubricate and alleviate these problems and thus prolong contact life.
The features:-
- Have good lubricating properties, even with heavy wiping contacts.
- Lowers resistance across contacts.
- Prevents tracking and shorting out.
- Eliminates arcing.
- Loosens and softens oxide films.
- Does not carbonize or form harmful deposits.
- Helps remove existing carbon deposits.
- Is not harmful to plastics and rubbers.
- Protects metal parts against corrosion.
Some of the above points may seem contradictory, in practice they are not. In a closed contact, the film of lubricant is squeezed thin. Because it is so thin, the current passes freely through the film across the contact. In fact, because the product takes up irregularities in the surface of the contact, resistance is lowered and effective contact area is increased.
When the contact begins to open, some of the grease strings across the gap, form bridges. As this happens, the electrical resistance increases from zero to infinity and the current is cut off. This takes place within a fraction of a millimetre and explains why no tracking or shorting out occurs in other instances. It is also this effect of reducing the flow of current, which eliminates arcing. ELECTRICAL CONTACT GREASE does not normally allow current to flow through it, in the thin film squeezed between contacts, it allows the current to flow freely.