Double Pole Double Throw Relay Symbol

It has 2 terminals and 4 connectors and you can look at the dpdt relay as the equivalent of 2 single pole double throw spdt relays.

Double pole double throw relay symbol. Sp and dp refer to single pole and double pole st and dt refer to single throw and double throw. Dpdt double pole double throw. It has one common terminal and 2 contacts. The 2 coil terminals is where the voltage is placed in order to energize the coil.

But most frequently used relays are spdt relay and dpdt relay both are acts as electromechanical switch. Look at the figure 1 2 the centre dotted line indicates that the dpdt switch is actually two spdt switches in one package. The main parts are all labelled and the circuit symbol is also shown the single pole double throw spdt relay is quite useful in certain applications because of its internal configuration. A double pole double throw toggle switch is a combination of two individual spdt single pole double throw switches connected in the single assembly.

An animation illustrating how an spdt relay works. Clicking the arrow button to reveal an internal cross section of the relay as it opens and closes. Single pole double throw spdt relay contains two coil terminals and common terminal then two switching terminals n o normally open n c normally close if there is not enough dc supply in. Sp switches control only one electrical circuit.

Dp switches control two independent circuits and act like two identical switches that are mechanically linked. A positive and negative voltage can be placed on either end. The dpdt relay double pole double throw is quite interesting and can be used in various scenarious including for changing the direction of a motor as you can see in the picture below. The polarity of the voltage does not matter.

This is the diagram below to learn all the pin terminals of a double pole double throw dpdt relay. Place the relay s rated coil voltage on these terminals.