Substation

Substation - switchgear for the chillers

The substation was a small single-storey building containing the main electrical switchgear for the whole Maybush site. It was divided into separate high voltage (HV) and low voltage (LV) rooms. Outside the Substation building was space for five transformers but it appears that only four were ever installed. The transformers were fenced off from general access by wooden slat gates.

Incoming electricity from the local electrical company (latterly SSE) came into the substation at 11 kV and was reduced down to 415/240 v by the transformers, there were HV breakers inside the HV side of the Substation allowing each transformer’s output to be cut off.

The three-phase 415/240 V power supplied from the four main transformers supplied the low voltage distribution board, this was located in the LV side of the Substation. Each one was set at a different phase of the supply (three phases plus neutral). In the event of loss of power from one of the incoming feeds then there were breakers that would have allowed it to be served by a different feed.

The LVDB also contained breakers for the refrigeration compressors (chillers) and like the refrigeration plant itself, there was provision for an extra chiller but that was never installed. The chillers used so much electricity that they were fed by separate 3.3 kV feeds, each with its own breaker in the substation.

The HV side of the substation contained a carbon dioxide fire suppression system that should have quickly extinguished any fire caused by the circuit breakers etc.

In around 2004, the low voltage distribution board (LVDB) was replaced as it was still using the original equipment and had become overloaded. It was At this time, the supply for Compass House was removed from the main Substation and provided with a separate and independent supply.

Historic substation images

Last updated on Wednesday 17 February 2021 by GaryReggae