"Dead-Front" Control Board

reproduced from:
Stage Lighting by Harrold Ridge, A.R.S.M., D.I.C., etc.
Houghton Mifflin Company, Inc., Boston
The Riverside Press
Cambridge 1928

A standard modern switch-board, designed and manufactured by the Strand Electric Co., is shown in Fig 22. The board is of the dead front pattern, i.e., no metal parts carrying current are exposed on the front, thus ensuring the operator against shock, a very necessary precaution in present-day installations, when the load is balanced on three or more phases of a supply with a potential up to 400 or 500 volts pressure.
The whole of the busbars and connections are at the back of the board, the handles only protruding through to the front.

The board illustrated is arranged for a four-colour scheme with master colour switches for each batten, footlights, etc. Sub-switches are also provided, dividing these into two sections on each colour. The stage dips are controlled by a master switch on each colour, and an individual switch on each stage socket.

Main black-outs are controlled by magnetic contactor switches which are placed under the stage and operated by the small switches on the centre panel on the board. This method ensures that a black-out is obtained without the noise of a heavy switch.

Below the switch are the wheel regulators for operating the liquid dimmers. They are arranged on four colour shafts and each wheel is capable of being operated individually or of being locked to the shafting, so that a master handle can operate all the wheels on each colour together. In addition, each colour bank is capable of being interlocked to the other colour in the same line, so that the two banks can be operated together.

The board is constructed in accordance with the Home Office rules and regulations.

Boards of this design have been manufactured recently and installed by the Strand Electric and Engineering Co., Ltd., 24, Floral Street, W.C.2, at:
Theatre Royal,
Glasgow King's Theatre,
Glasgow Mile End Pavilion,
London Lyceum Theatre,
Edinburgh Alhambra Theatre,
Glasgow Birmingham Empire, etc

Such a board ready for installation costs from about £250 to £300.