The clock is on a battery system which is continually recharged by the mains electricity supply, so like a laptop, it continues working when the power supply is interrupted.
The battery has about 6 hours running time in it, although it depends on the time of the day because the power drives three motors, the main clock, the strike (the hours) and the chimes (the quarter 'Westminster' chimes). The chimes draw the most power and depending on the time of the day can run the battery down faster with the highest drain being during the day and together with the strike late morning, when the clock strikes 10, 11 and 12...
The battery maintained the clock for about six hours, which was unfortunately about 20 minutes less than the duration of the power cut for the supply, so when the power was restored the clock restarted, showing the time 20 minutes late.
The second issue is that the computer can only adjust the minutes, not the hour and can only do so to plus or minus five minutes in any hour, so it can not 'catch up' the missing 20 minutes, Upchurch Parish Council is grateful to the residents who pointed out the clock was wrong.
Finally, the radio signal that keeps the clock in check is susceptible to poor weather conditions and by definition, a named storm is a poor weather condition, and to complete the 'perfect' storm (pardon the pun) regarding the impact on the clock, the high winds in the clock tower knocked the radio receiver from its position, and it was unable to receive the signal when it recovered.
These faults are all remedied, and the clock should be fine until it is next serviced, which will include an adjustment to the computer's internal clocks as a standard part of the service.
The Council hopes this helps residents understand the reasons for the clock's inaccuracy for a few days after the storm.
Upchurch Parish Council
