BS EN 3773-004:2014

What is BS EN 3773-004 - Product standard for UNC thread terminals about ?

BS EN 3773 is a European standard on aerospace that discusses guidelines on single-pole circuit breakers as well as UNC thread terminals. 

BS EN 3773-004 is the fourth part of a multi-part series that specifies the characteristics of single-pole circuit breakers, temperature compensated with a rated current from 1 A to 25 A, used in aircraft on-board circuits at a temperature between – 55 °C and 125 °C and at an altitude of 22000 m max.  

These circuit breakers are operated by a push-pull type single push button (actuator), with delayed action "trip-free" tripping. They will continue to function up to the short-circuit current.  

Who is BS EN 3773-004 - Product standard for UNC thread terminals for ?

BS EN 3773-004 on the product standard for UNC thread terminals is relevant for: 

• Aerospace avionic electrical and fibre optic technology
• Manufacturers of circuit breakers 
• Aerospace and defence industries 
• Designers of circuit breakers 
• Aircraft electrical manufacturers 
• Design engineers for airplanes
• Quality control personnel for aircraft and related applications 

Why should you use BS EN 3773-004 - Product standard for UNC thread terminals ?

UNC is generally used for mass production of threaded fasteners, such as bolts, screws, nuts, etc and are often used within the agricultural industry because of their strong coarse threads. The thread is deeper and more generic than that of a fine thread and allows for easy removal, whilst they also have a higher tolerance for manufacturing and plating.  

A pole refers to the number of separate circuits a switch can control, a single-pole switch can operate one circuit. It has one switch and only needs to connect two wires. 

A single-pole breaker is mainly used for the general lighting circuit of houses and installed in a standard outlet with a two-slot outlet receptacle. As a manufacturer of circuit breakers, you can use BS EN 3773-004 to improve the production of circuit breakers. 

BS EN 3773-004 provides best practice guidance on the dimensional characteristics, mass, material, marking, packaging, and panel mounting. 

BS EN 3773-004 also provides you with the mechanical, electrical, environmental, qualification and material tests of single-pole circuit breakers. This assists in building the best quality single-pole circuit breakers that support aircraft electrical systems that are efficient as well as durable. 

With obedience and compliance to BS EN 3773-004, you can enhance the efficacy of single-pole circuit breakers and manufacture a standardized high-quality product to ensure the reliability of your products and build trust in their use throughout the aerospace supply chain.