| 摘要 |
<p>A demand control apparatus includes a switch (26) in the control signal line (16) of an electrically powered piece of equipement (22). The switch (26) is controlled by a digital recycle counter (24) so as to periodically cycle off and on during times when an equipment generated control signal is present in the control signal line (16). The control signal line (16) could be a thermostat control line on a standard air conditioning unit and the equipment generated control signal would normally correspond to the thermostat calling for cooling. When the switch (26) is opened the equipment load (20) reacts as though the thermostat has been satisfied. When the equipment generated AC control signal is sensed in the control signal line (16), a digital counter (24) is activated to hold the switch (26) open until a preset number of AC pulses have occurred. The switch (26) is then closed until a second preset number of AC pulses have occurred. The open-closed cycle is repeated as long as the equipment control signal is present. The cycle periods can be adjusted in response to external conditions such as ambient temperature or line frequency. In multiple load applications, load diversity is improved and aggregate demand is reduced after power outages. Sequential start of diverse and multiple loads is assured.</p> |
