초록 ▼

A spa control circuit is provided for regulating a water circulation and heating system in a spa or hot tub or the like. The control circuit comprises a thermostat circuit and a high temperature limit circuit, both of which receive a temperature signal from a common temperature sensor. A safety circ

A spa control circuit is provided for regulating a water circulation and heating system in a spa or hot tub or the like. The control circuit comprises a thermostat circuit and a high temperature limit circuit, both of which receive a temperature signal from a common temperature sensor. A safety circuit responds to sensor failure to prevent operation of the circulation/heating system. A latching relay ensures system reset in the same operational state following a power outage. An arc suppression circuit substantially prevents arc damage to relay contacts subjected to frequent opening and closing in response to on-off cycling of the thermostat circuit. In a preferred form, the control circuit components are mounted within a compact housing having a heat transfer member in heat exchange relation with circulating spa water, whereby the spa water is used to prevent overheating of the control circuit components.

대표청구항 ▼

A control circuit for a spa having a tub for receiving a supply of water and heater means energizable for heating the water, said control circuit comprising: temperature sensor means responsive to the temperature of the water for generating a temperature signal representing water temperature; switch

A control circuit for a spa having a tub for receiving a supply of water and heater means energizable for heating the water, said control circuit comprising: temperature sensor means responsive to the temperature of the water for generating a temperature signal representing water temperature; switch means movable between opened and closed positions for de-energizing and energizing the heater means; and circuit means responsive to said temperature signal for moving said switch means between the opened and closed positions to prevent overheating of the water; said circuit means including means for detecting failure of said temperature sensor means and for responding thereto to move said switch means to de-energize said heater means; said switch means comprising a high temperature limit relay, and wherein said circuit means comprises a high temperature limit circuit responsive to said temperature signal for moving said high temperature limit relay to de-energize the heater means when the water temperature reaches a predetermined upper limit; said switch means further comprising a thermostat relay, said circuit means having a thermostat circuit responsive to said temperature signal for moving said thermostat relay between opened and closed positions to respectively energize and de-energize the heater means to maintain the water temperature within the limits of a normal operating range less than said predetermined upper limit; said temperature sensor means comprising a single temperature sensor for generating said temperature signal coupled to both of said high temperature limit and thermostat circuits; said circuit means including manual reset means for moving said switch means to energize the heater means, said circuit means including temperature responsive mean and said means for detecting sensor failure for independently moving said switch means to de-energize the heater mean; said circuit means further including a latching relay coupled to said switch means, said latching relay having a switch arm movable between a power-on position for moving said switch means to energize the heater means and a power-off position for moving said switch means to de-energize the heater means, said temperature responsive means and said means for detecting sensor failure being connected to said latching relay to move said switch arm to the power-off position respectively in response to the water temperature reaching said predetermined upper limit and in response to sensor failure, said manual reset means being connected to said latching relay to move said switch arm to the power-on position.