312-4

Rotary Switches

A rotary switch is a switch operated by rotation in which the contacts are usually on the end face of a rotor. It includes a circular housing containing a rotor, which has a fingertip mounted to it, and contact arms, which are attached to the rotor either permanently or by use of a shaft. Rotary switches are used extensively in electronics and appliances as a simple and reliable way of controlling the flow of electricity in a circuit.

312-4 Application Field and Working Principle

The 312-4 rotary switch is a multi-pole, multi-position switch suitable for a wide range of AC and DC control applications. It is ideal for use in domestic and industrial control panels, electronic circuits and automated control systems. The switch consists of a stationary contact assembly and a rotating contact assembly which is actuated by a rotational drive. The mechanism provides four distinct positions with no possibility of contact bridging.

The stationary contact assembly consists of four contact arms arranged in a cross formation. An electrical connection is made at one set of contact arms with the other set being connected to the load. As the rotor of the 312-4 rotary switch is moved, a series of electrical connections are made between the stationary contact arms and the rotor contact arms. This action is performed in a precise manner depending upon the direction of the rotor’s rotation.

The rotor of the 312-4 rotary switch is driven by a cam or lever and is able to rotate through four distinct positions, each of which is designed to make or break a predetermined set of electrical connections. The contact arms are arranged in such a way as to ensure that no more than one electrical connection can be made between the stationary contact arms and the rotor contact arms for each position and that no contact bridging exists between any of the contacts.

The 312-4 rotary switch is robust and simple to operate and is suitable for most AC and DC control applications. It is highly reliable with a rated lifespan of 50,000 operations and is shock resistant with a vibration rating of up to 0.3 g. The device has an IP20 protection rating, making it dust-tight and suitable for use in harsh industrial environments. Additionally, the switch is rated for up to 250V AC and 1A (resistive) making it suitable for most low voltage control applications.