Specifying an electrical switch

ELK 1Key factors to consider when specifying an electronic switch, are identified by Guy Lorenzo, product marketing manager, Switch Products, Bulgin.

Q: Which type of switch do you need?

A: A wide range of different switches is available to suit different applications. Whether you need a rocker switch, or a pushbutton, a toggle or a slider switch, Bulgin and Arcolectric (both Elektron Technology brands) can meet specific needs. Options include thinline, miniature and standard rocker, high in-rush, round, toggle, pushbutton, vandal resistant, refrigerator and slide switches.


Q: Do you need an illuminated switch?

A: Depending on the application, an illuminated switch may be preferable to one that is unlit. Some rocker and pushbutton variants can be supplied with neon, filament and, in some cases, LED illumination.


Q: How many poles and throws are required?

A: Consider whether a simple on-off switch or something more complex is needed. Bulgin offers a wide selection of switches, including single pole, single throw (SPST), single pole, single throw – normally open (SPST-NO), single pole, double throw (SPDT), double pole, single throw (DPST) and double pole, double throw (DPDT), as well as more complex variants.


Q: What is the function of the switch?

A: Depending on the application, think about whether it is better to use a momentary or a maintained switch, and which type is most appropriate: for example an on-off, on-on, on-off-on or momentary on version.


Q: Which type of termination is required?

A: Various types of termination are available – quick connect, solder lug, screw, PC – in different sizes. Choose the most suitable size and type for the particular application.


Q: Which switch rating do you need?

A: When specifying a switch, it is important to consider the current, voltage, temperature range and operating life required. Bulgin can supply switches for both high and low power applications.


Q: How much space is available?

A: Before choosing a switch, check the dimensions of the panel opening. Also investigate whether there are any space constraints – width or depth – behind the panel. Bulgin offers a range of switches that can be supplied in different panel opening and bezel sizes.


Q: What is the application?

A: The type of switch selected will depend on where it is being used and what it is controlling. The specific application often determines the choice of switch, and may require the use of sealed or splash-resistant products.


Q: Are any approvals necessary?

A: In some cases, agency approvals may be required, and it is important to ensure that the switches under consideration are appropriately certified. Most Bulgin switches are approved by internationally recognised agencies, including ENEC, UL and CSA.


Q: Are any particular colours or markings required?

A: The customer may request specific colours, which may be standard or custom. Consider the type and colour of any marking that is needed on the actuator. Bulgin can supply rocker and pushbutton switches in a wide variety of colours.


Q: What quantity?

A: Determine the number of pieces the customer needs. Not only does this help with pricing, it is also a determining factor when custom variants are requested.


Q: Are there any custom requirements?

A: Our engineering design and fabrication resources can meet most challenges, and have the capability to modify Bulgin switches to meet custom applications and requirements.