Most industrial control systems require a space where interactions occur between the human and the machine. This is commonly known as an operator interface, and switches form a vital component in these areas, enabling the operator to quickly turn components of the machinery on and off.
At first glance, selecting something as uncomplicated as a switch might seem to be of small importance. However, only after investigating the application, the environment within which it will operate, and in considering all possible use cases for their switch of choice, can designers arrive at the optimal switch solution.
If the switches in an operator interface aren’t optimally selected, it could in the long term negatively affect the functionality of the machinery, and no doubt might cause some frustration on the part of the operator as well. A poorly-planned switch choice can also increase the time it takes to perform a particular operation, and in a high-pressure environment this can cost not only valuable time but could even lead to equipment failure and possible injuries.
Here are three questions that should be asked:
To what degree is the operator interface exposed to dirt, dust, moisture and vibration?
This will determine how rugged the switch should be. Ideally, operator interfaces in dirty or wet environments will need to be sealed and be Ingress Protection (IP) rated to prevent dirt from building up and moisture from entering the equipment via the switch mechanism, but if they will be used in an interior environment a less rugged option would likely take up less space.
How hard is the switch likely to be pressed?
If the operator is likely to be wearing gloves, this could increase the force with which the switch is pressed. Also, the location of the switch in relation to the likely position of the operator and whether the switch is comfortably within arm’s reach or not can be additional factors.
How many times is the switch likely to be pressed per day?
From this calculation, you can work out the expected number of operations over a year so you can find a switch with a lifecycle that can withstand repeated operation over the next 5 to 10 years without failure.
So what exactly is a rocker switch? As the name suggests, rocker switches rock back and forth between the off and on position. When one side is pressed down, the other side will rise up. Most of them provide a ‘positive click’ feedback to let the user know the switch has changed position successfully. Typical applications for these switches include commercial and agricultural vehicles, surge protectors, computer power supplies, industrial assembly lines and many other types of industrial machinery panels.
Some rocker switches with independent circuitry can be backlit to show their presence and function in low light levels. Others can be illuminated to show whether the switch is on or off.
On any operator interface, if you decide to include rocker switches in your design, you’ll need to ensure you have enough space for the switch and information about what the switch is for.
Bulgin’s high quality rocker switches includes a vast range of single pole and double pole options available in various sizes, colours, terminations, actuator types and ratings up to 16A, 250V AC.
With termination options including splash proof features, PCB pins, solder lugs, screw terminals and quick connect tabs in addition to on-off, on-on and on-off-on functions; Bulgin’s rocker range provides the ideal switch solution for most electrical appliances and equipment.
Carrying UL, CSA & ENEC certification (depending on product series), this wide array of full-sized to miniature rocker switches allow for virtually any design configuration in a wide range of industry applications and environments.
For more information on the Bulgin switch range, please visit: https://www.bulgin.com/us/products/range/switches.html