Touch Plate 2-Wire Low-Voltage Relay with switching block and pilot wires. Single Pole Single Throw mechanical latching function. The main contacts are rated 20A 120/277/347VAC. The low-voltage control circuit is 28VDC. This also replaces older discontinued non-pilot light models 1200, 1550-A, 1550-B, 2500-B and 4000. The only physical difference is the size of the relay base. The 4000 and 3000 relays are about 1" larger in size. This relay is a replacement for Touch-Plate systems installed between 1946 and 1985. The older relays have two low-voltage wires coming out from the top of the cylinder that connected to the switches. The two wires coming out from the bottom connect to the line-voltage feeds. With the 3000 relay, you simply connect the line-voltage feed wires to the two screw terminals on the body of the relay. It doesn't matter which terminal you connect to because the line-voltage connections are not polarize and therefore either one can take the hot feed and the other the switching connection.
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