D4B-4A11N

Snap action, limit switches are commonly used in sensing and control applications. The D4B-4A11N is a normally closed, single-pole, single-throw (SPST) device with a circuit opening travel of approximately 0.020 to 0.020 inches. This device has a variety of applications, including light sensitive switching, temperature-sensitive switching, flame sensing, air pressure sensing, and traffic signal sensing.

The working principle of the D4B-4A11N is based on an electrical or mechanical contact created by a single pole (contact) being pressed against a fixed contact. In a normal position, the contact is open. When an actuating force is applied to the contact, it will move away from the fixed contact and a make/break contact is created. This state is maintained until the force is removed, and then the contact will move back to its original position, which is open.

The D4B-4A11N can be used in various types of operational scenarios, including general on/off functions, signal transmission, snap action reply (as a monitor of a continuous signal), crash relay, NC switch, and system interlock. It is most commonly used in traffic signal (using a sensing coil), alarm systems (using temperature sensing element), light-sensitive switching applications, HVAC systems, and flame sensors (using a temperature sensing element). The switch is most effective in applications that require rapid switching, such as in fire protection systems (used as part of a smoke detector).

In terms of electrical characteristics, the D4B-4A11N has a maximum current rating at 25A and a maximum voltage rating of 250 VAC. It has a contact resistance of less than 25 mOhm and a dielectric strength of 4KV. The control range is approximately 0.020 to 0.080 inches with a maximum release force of 1.0 ounce-force. It is UL listed and is approved by the CE mark.

The D4B-4A11N is a reliable and durable snap action, limit switch. It is designed to effectively and efficiently satisfy the needs of industrial and consumer applications where immediate feedback and precise control is required. It is designed to be used in applications that require rapid switching, as well as in various other operational scenarios, from general on/off functions to system interlocks. Its high electrical and mechanical ratings make it suitable for use in a variety of environments.