Form 2 defines overall assemblies which are enclosed to provide protection against contact with any internal live parts or components, and where there is internal separation of the busbars from functional units.
The following general conditions apply;
- Busbars are separated from functional units
- Functional units are not separated from other functional units.
Compliance with the requirements of Form 2 may be offered by EIEMA manufacturers by any of the three methods. Specifiers and Users should clearly state their preference.
FORM 2 (Form 2a)
Basic form as above. However, with this method terminals are not separated from the busbars, or each other. The actual means of separation is not defined in the Standard.
FORM 2 Type 1 (Form 2b Type 1)
Main criteria as FORM 2. Busbar separation is achieved by insulated coverings, e.g. PVC sleeving, wrapping or coating. Terminals are therefore separated from the busbars, but not from functional units or each other.
FORM 2 Type 2 (Form 2b Type 2)
Main criteria as FORM 2. Busbar separation is achieved by metallic or non-metallic rigid barriers or partitions. Terminals are therefore separated from the busbars, but not from functional units or each other.