Switch Basics: A Guide to Push Button Switches
Switches have so many different attributes to keep up with, so we have put together a little guide of the basics!
What is a Push Button Switch?
A pushbutton switch (push switches) are devices that are pushed to make or break an electrical circuit. Or to put simply, an object you push to make a device do or stop something. These come in all shapes and sizes, with a multitude of options. So lets run through the basics.
Push to Make or Push to Break Switch?
A Push to make or ‘Normally Open’ (NO) switch is when an electrical flow is activated in a circuit when the button is pressed. And when the button is released the circuit is then broken and the electrical flow is stopped. This is the most common switch type.
Whereas a Push to Break switch or ‘Normally Closed’ (NC) works in the opposite way, once pressed it stops an existing electrical flow through the circuit.
Poles and Throws
SPST (Single-pole, single-throw) switch has only got one output and one input.
SPDT (Single-pole, double-throw) switches have three terminals, one common pin and two pins which contend for connection to the common. Most suited to devices selecting between two power sources.
DPDT (Double-pole, double-throw) switches are essentially two SPDT switches that control two separate circuits and are switched together by one single actuator.
Momentary or Latching function
A momentary switch only works when there is force pressing the button, once this force is removed the switch is no longer engaged. A latching switch maintains the state once pressed, until the push button is pressed again to release the switch.
PCB or Panel mounting?
A PCB switch is a switch that is directly mounted onto a PCB (Printed Circuit Board). Surface mount PCB switches (SMD/SMT) are designed to sit flat, directly on top of a PCB. Through-hole or ‘thru-hole’ PCB switches are inserted into a drilled hole on the printed circuit boards and soldered to pads on the opposite side. See our range of PCB switches here.
Panel Mount switches are inserted from below into a hole in a panel. Panel mount switches are designed to sit outside an enclosure. See our guide to panel mount switch pins here. For our range of panel mount switches click here.
LED Illumination Options
RJS supplies both non-illuminated and illuminated push switches. Choosing what type will depend on the function and design of your product. There is a wide range of LED illumination options including single, bi-colour, dual colour or RGB LED illumination. How the illumination is displayed also varies. Variations include;
Ring Illumination
Dot Illumination
Full Illumination
Custom Illumination
IP Ratings
IP ratings looks at the protection of factors such as dust and water/moisture. For example, if your switch needed to be weatherproof you would require a switch with a higher IP rating to ensure the protection of the switch and its function. Read our detailed blog post on IP ratings here.
Subcategories of Push Button Switches
IP ratings looks at the protection of factors such as dust and water/moisture. For example, if your switch needed to be weatherproof you would require a switch with a higher IP rating to ensure the protection of the switch and its function. Read our detailed blog post on IP ratings here.
Still overwhelmed? Contact our sales engineers today, we can help guide you to select the right switch for your project!
How to place an order?
Interested in our products? Speak to us today!
We operate Monday – Thursday 8 am – 5 pm and Fridays 8 am – 4.30 pm, call us on +44 (0)1234 213600 to speak to our Sales Engineers or e-mail us on [email protected] alternatively, leave us a message using our online contact form.
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