One of the first questions asked of any supplier of electrical equipment is whether the product will be labeled to CSA/UL standards. The critical words used are "approved" or "certified". Electrical equipment cannot be "certified". CSA is a quality audit organization that ensures the public that the equipment purchased is built in accordance with certain standards.

These standards are developed and reviewed by various agencies including utilities, insurance companies, and inspectors. The word "certified" legally implies that once the design is created there shall/must be absolutely no modifications or changes from the originally established C.S.A. files. Equipment testing is done to verify these designs and it allows only certain economies in design to be taken. We call these "design integrated equipment ratings". When there has been a device change in the product portfolio, then a complete retest program with C.S.A has to be undertaken.

Often you hear words such as "extrapolation" used to describe how a product "meets" the C.S.A. design standards, however to use such an approach as "interpolation" or "extrapolation" violates the certification.

It is therefore important that you purchase "unconditionally rated equipment". You then are purchasing equipment that has been tested as a stand alone item that will be technically correct and insurable, no matter what the change is in protective devices.