on both dials: 'GENTS' | OF LEICESTER | MADE IN ENGLAND'. Around keyhole: 'GENT & CO. LTD | LEICESTER | PULSYNETIC | TRANSMITTER'. Plaque at base of case,with indication of current strength: 'INDICATION OF CURRENT STRENGTH. | When the Impulse Lever is not replaced until the pendulum swings to the right, it is an absolute indication that the current operating the PUL-SYN-ETIC system is NOT sufficient; therefore augment or give battery attention, IMMEDIATELY'.
Overview
This clock exploits the accuracy of a pendulum for a new world. It was used to monitor mains turbine frequency in the early years of the National Grid. The upper dial is an electric pendulum clock; the lower is a synchronous motor. The job of the power station attendant was to keep them aligned. If the lower dial was ahead, the generator was too fast. If it was behind, it should be sped up.
In depth
This clock was intended for use in a power station to monitor the frequency of the mains turbines – set at 50 cycles per second in the UK and 60 cycles per second in the USA. It combines a standard Gent C7 movement and dial (mounted above) with a synchronous motor clock (below). The job of the power station attendant would have been to monitor the two times displayed and ensure they align: if the electric clock is running fast, the generator must be slowed down; it the electric clock is running slow, it should be sped up. This is one of three frequency control clocks in the collection at The Clockworks.
