Momentary Rating

The rating of a device to withstand momentary, very high current, without incurring damage.

Mobile Transformer

A transformer that often is mounted on a leak proof base and can be installed and operated in a semi-trailer, box truck or sea freight container.

Mid Point Sectioning Substation

A substation located at the electrical interface of two sections of electrified railway. It contains provision for the coupling of the sections electrically in the event of loss of supply to one section.