CLOCK No. 56

B 1361
Issue 4, Oct 1970

Clock No. 56B

One of the standard synchronous clocks at present used by the PO. The movements are described in B 1351.

Synchronous clocks are suitable for use only in areas where the mains supply is reliable. The basis for provision is given in B3001.  The types used in the PO are all non self-starting for use on a supply of 200-250 volts ac, single phase, 50 Hz, with a frequency which is time controlled.  They should not be installed where time keeping is of vital importance.

Clock No. 56B
Similar to Clocks No. 52B, but with circular cases.  When used in a public office window, a clock of this type should be mounted by means of a Bezel, Clock No. 1 (Drawing P/T 102), which is described in B 1128. Superseded for new work by Clocks No. 76B.

Picture shows clock mounted in Bezel, Clock No. 1.

A pulse version was also available and this was the Clock No. 56A.

Drawing No. P/T 93.

Drawing - 63009.

No. Overall diameter Diameter of dial Depth (back to front)
56B 14.75in. 12in. 3.6in.


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Last revised: November 16, 2023