Weather warning for snow and ice across parts of the North West from Friday evening through to Sunday morning. For more information click here.

Telecontrol and system operation

Telecontrol and system operation


Telecontrol of the electricity network is enabled via primary and secondary computer based real time Supervisory Control And Data Acquisition systems, referred to as SCADA. Primary and secondary SCADA systems allow the control and monitoring of the 132kV, 33kV, 11kV and 6.6kV networks.

System control engineers

Full time system control engineers at the Distribution System Management Centre (DSMC) in Manchester manage the networks.

The level on monitoring and control varies by voltage as follows:

  • the 132kV and 33kV networks are fully controlled from DSMC by the primary SCADA system
  • the outgoing High Voltage (HV) circuit breakers at primary substations are also controlled from DSMC by the SCADA system
  • selected switches on the rest of the 11kV and 6.6kV networks are monitored and controlled via the secondary SCADA system which has a separate set of central servers.

Supervisory control and data acquisition monitoring

Control of both the primary and secondary SCADA is implemented through a single graphical user interface in order to ensure a standard interface for the control engineer.

Primary SCADA monitoring is carried out through outstations and at all grid and primary substations. Grid and primary substations communicate with the central servers over a mixture of copper pilots, optical fibre and telemetry scanning radio.

The secondary SCADA system is based on the Remote Terminal Units (RTU) communicating with the central servers over radio networks and controls the urban and rural HV network.

Control and operation

The electricity distribution network is controlled and managed from the centralised DSMC, from which all operations on the HV system are co-ordinated.

A system of field control is sometimes adopted for management of a small section of the network where work is being carried out. Authorisation to operate the distribution network is only given after adequate training and assessment.