Alarm for signalling excessive use of household electricity - produces intermittent sound of variable amplitude and frequency as function of consumption

摘要

The appts. emits a mildly annoying sound when a user exceeds a predetermined energy consumption. The circuit is connected to the electrical supply adjacent to the meter. The connections are made by electromagnetic or optical coupling and the circuit produces two sounds. One sound is intermittent with an amplitude and frequency which varies with the electrical consumption. A second sound signal is emitted to indicate that another piece of equipment has been switched on. Controls enable the minimum threshold consumption to be set as well as the maximum level of operation and also the sound amplitude.