Switched-On Sourcing of Switches

Alan Cook Managing Director of 4most Electronics Limited has been in the electronics industry over 25 years and here are his top 10 tips to ensure buyers make a “switched-on” decisions when sourcing switches  

Market trends in what is sometimes referred to as the Human-Machine-Interface (HMI) world are being driven by product marketing departments to tablet style touch screens as this form of control interface is seen as a major selling feature much desired by end customers. However touch screens have major drawbacks in many applications – cost of a bespoke design, ruggedisation, waterproofing, operation by gloved hands, illumination and tactile response to actuation etc.

The humble electromechanical switch and rotary encoder are far from outmoded and are still the preferred HMI solution of choice for very many applications in white goods, automotive, aerospace, medical, IT, audio/broadcast, industrial systems and many more.

Most electromechanical switches come in the form of rotary, toggle and slide actuation. With options of number, material, change-over function and current and voltage ratings of contacts, waterproofing, illumination, actuation force, proof against ESD (electrostatic discharge - a consideration in medical and some industrial applications), solder tag, PCB or SMT mounting and number of operations required during end product life.

Rotary encoders are now widely used instead of rotary switches as they offer greater flexibility and multi-function programming options. Rotary encoders are commonly found in audio and automotive applications and similar function, illumination, ruggedisation and operational life requirements have to be met as does specifying the correct encoded output signals for the host system.

With so many functional, operational and environmental requirements to be met, working with a specialist supplier is essential. The following check list will ensure the best technical and commercial solutions will be found;

1 - Work with a distributor who has sufficient product knowledge and specialisation to understand and assist in selection process as early in the design process as possible.

2 -Involve your design engineers in dialogue with your supplier at the beginning of a project to ensure a cost-effective component will be readily available

3 - Ensure your supplier has a flexible approach to problem solving.

4 - And has depth of product availability to offer alternatives when necessary.

5 - Your supplier should have the ability to offer semi- custom and custom solutions if required.

6 - And provide in-house technical support should the need arise.

7 - Ensure your supplier supports your production requirements and can offer call-off order and buffer stock facilities

8 - Work with a supplier who can meet your lead-time requirements ensuring they can receive delivery of the product within the required lead time.

9 - Manage the life-cycle of your end product and ensure your supplier will provide early warring if the switch is becoming obsolete or subject to any changes within the time scale of your production.

Foremost Electronics serves a wide number of diverse markets from industrial, instrumentation, audio/broadcast, rail, medical to education. Established in 1989, Foremost Electronics Ltd. are long established agents and distributors of electro-mechanical components including switches, connectors, cabinets, enclosures and handles, control knobs, thermal fuses and optoelectronics. Foremost are also a supplier of joysticks and controllers for both OEM and stand-alone applications and have specialist online stores for Rotary Switches, IP Joysticks and Electric Vehicle Connectors and Accessories www.enclosures4u.com

 E: Emma Kempster Emma@4most.co.uk