Unit Substations

A unit substation consists of one or more transformers mechanically and electrically connected to and coordinated in design with one or more switchgear or switchboard assemblies These substations are used for effective electrical power distribution in medium voltage to low voltage distribution systems.

• There are:

- integrating oil or dry type Transformers
- integrating metering and protection

• And can ensure that:

- High operation reliability
- Operating personnel safety
- Suitable for building, infrastructure, and industry.

All interconnecting equipment between medium voltage, transformers and low voltage are factory tested. The medium voltage compartment contains a ring main unit (RMU) fused disconnect switch or circuit breakers. Oil type or SF6 type are provided as per customer specification. The transformer is specifically designed to operate inside the substation enclosure (normally IP23) with restricted ventilation. The low voltage compartment contains the distribution boards with or without a metering system. Either molded case circuit breakers or high rupturing capacity fuses are used for connection to outgoing feeders. Fittings and accessories are provided as per standards or as per customer requirement