Dimmer switch with adjustable high-end trim
First Claim
1. A load control device with an adjustable high-end trim for controlling the amount of power delivered to an electrical load from an AC power source, the load control device comprising:
- a bidirectional semiconductor switch coupled in series electrical connection between the source and the load, and operable to control the amount of power delivered to the electrical load between a low-end trim and the adjustable high-end trim, the semiconductor switch having a control input for controlling the semiconductor switch in response to a firing voltage signal derived entirely from analog control circuitry; and
a user-accessible adjustment actuator for adjusting the high-end trim of the load control device from a first level to a second level lower than the first level, the adjustment actuator mounted on a front surface of the load control device, the adjustment actuator inaccessible to a user when a faceplate is mounted on the load control device, the adjustment actuator accessible to a user when the faceplate is not mounted on the load control device;
wherein actuations of the user-accessible adjustment actuator have substantially no affect upon the low-end trim of the load control device.
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Accused Products
Abstract
A dimmer switch has a user adjustable high-end trim. The dimmer switch includes a bidirectional semiconductor switch, such as a triac, for controlling the amount of power delivered from a source of alternating current power to a lighting load, such as an electric lamp. A user-adjustable timing circuit controls the conduction time of the triac from a minimum time to a maximum time to control the power delivered to the load between a low-end trim and a high-end trim. The timing circuit includes a user-accessible switch that allows a user to reduce the high-end trim from a first nominal level to a second reduced level, lower than the first level, without substantially affecting the low-end trim. The dimmer switch advantageously uses less energy and the lifetime of the lamp is extended when the second reduced level of the high-end trim is selected.
25 Citations
20 Claims
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1. A load control device with an adjustable high-end trim for controlling the amount of power delivered to an electrical load from an AC power source, the load control device comprising:
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a bidirectional semiconductor switch coupled in series electrical connection between the source and the load, and operable to control the amount of power delivered to the electrical load between a low-end trim and the adjustable high-end trim, the semiconductor switch having a control input for controlling the semiconductor switch in response to a firing voltage signal derived entirely from analog control circuitry; and a user-accessible adjustment actuator for adjusting the high-end trim of the load control device from a first level to a second level lower than the first level, the adjustment actuator mounted on a front surface of the load control device, the adjustment actuator inaccessible to a user when a faceplate is mounted on the load control device, the adjustment actuator accessible to a user when the faceplate is not mounted on the load control device; wherein actuations of the user-accessible adjustment actuator have substantially no affect upon the low-end trim of the load control device. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20)
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Specification