Although there is a fair amount of interest in trolley buses and trams, there is very little information readily available about the electrical distribution and sub station equipment that was used. At present, the BCMTG uses modern solid state apparatus to provide the required D.C. supply for the operations on the site.

We do however have some considerable data on file (but alas not on computer) detailing the Wolverhampton system sub station apparatus - this even extends to the wiring diagrams themselves.

Most of the rectifier sub stations were located within the existing sub stations of the Midlands Electricity Corporation. Their M.V. was 6500 volts. This was transformed down to 600v and converted to D.C. by mercury arc rectifiers. A picture of a typical (but alas not a black country) sub station is shown below:

The output from the rectifiers was taken by underground heavy duty feed cables to feeder pillars where there would be isolating links and/or perhaps a circuit breaker, before the supply was feed up a convenient traction pole and onto the overhead wires. The overhead itself was segmented into approximately half mile sections, with each section having its own feed. In this way (since there would only be a few vehicles in any section at any time) the voltage drops on the feed cables would be kept to a minimum.