During the swing of the pendulum through the
zero position a platinum contact is closed and
gives the magnet at the end of the pendulum
an impulse through the magnetic coil. The swing
of the pendulum moves with the aid of a small
lever a ratchet wheel that in turn moves the
movement of the clock.
The timekeeping of these electric clocks is
very much higher than the one of the usual mechanical
clocks with a mechanical escapement. Most important
is the correct function of the contact.