摘要 |
Lighting apparatus for independently controlling the lighting level in several areas or zones. For example, each zone has two fluorescent lamp units, one connected between the power lines through the contacts of a first low voltage AC latching relay, and the other which produces about half the light of the first connected between the power lines through the contacts of a second relay. Each relay has three terminals. When a low voltage AC signal is applied between a first terminal and a common terminal, the relay is latched closed; and when a low voltage AC signal is applied between a second terminal and a common terminal the relay is latched open. The common terminals of the two relays of each zone are connected together to provide enable connections identifying each zone. The first terminals of all the first relays are connected together, the first terminals of all the second relays are connected together, the second terminals of all the first relays are connected together and the second terminals of all the second relays are connected together to provide four data connections. By applying momentary low voltage AC signals between appropriate data and enable connections, any desired combination of lamps can be turned on or off.
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