One of the most common items found in every electrical circuit and commercial electronics are switches. These come in many different shapes, sizes, and functions, They are a necessary component as they are used to open or close a circuit. The problem with switches is that they all have mechanical parts in them that move. These mechanical parts can wear, bend, and break. Without a functional switch your circuit and possibly your entire device can be out of commission.This post is going to go through the steps that our technicians and engineers use to help find switches that will work for our customers.


  First, we need to identify what kind of switch that is needed. Today I am going to take a quick look at one of the most common switches we deal with which is the Rocker Switch. Although I will be going through this specific section, you will find that the way I narrow down my required specifications will often be the same steps I would use if I was looking for a toggle or pushbutton switch as well.Just selecting rocker switches can be a little overwhelming with over 10,000 different options. When looking for a replacement switch we start with 3 main attributes or specifications.

  How does your switch function?What is the size of the Panel cutout or hole that the switch mounts in?What are the voltage/amperage ratings on the side of your switch.

  So, the first thing I am going to do is select in-stock as I am looking for options that can ship today. If you are not in a hurry or don’t find any options, you can deselect this at any time during your search. This step takes my options from 10,000+ down to 1,500.

  What is the switch function. My switch today is very simple. The function is on-off and it will stay in the individual position when chosen. Here I have selected on-off and narrowed my options to 500.

  What is the size of the panel cutout? Since this is measured in mm I am measuring mine and it appears to me 30mm long and 22 mm wide. Knowing there is some room for error I will normally look at any switches that are within 10% of my measurements. I will also ask my customers if there is room to make this cutout larger if we have an available switch.

  By selecting all options with a length or 27-33mm and a width of 20-24mm I have narrowed down to only 100 options.

  What are the voltage and current ratings? These ratings should be found on the side of your switch. On the side on my switch I see the following numbers 20A 125VAC and 16A 250V-.

  Since I know my vacuum is running on 110V I am going to go with the higher 20A rating on my search. I have selected all the switches with a 20A or higher rating. Most of the switches on the Digi-Key site will have the voltage ratings associated with the highest current rating. In this instance, had I searched for the 250V rating it may have eliminated the switch I was looking for.

  Using these 3 steps I have narrowed my possibilities down to a much more manageable 50 options.

  Next I want to verify the circuit for my switch. I can generally do this by looking at the bottom of my switch.When looking at the bottom of my switch I have four .250" quick connect terminals. They are marked 1, 1a, 2, 2a. This is a quick indication that I have two circuits (Double Pole) and I know that I only have one throw as my switch is simple on-off. Using this information, I can select DPST (Double Pole Single Throw) for a circuit. I seeing that I have .250" quick connects I can also select that for my termination. In this instance, I have options on termination for just .250" quick connect and .250" quick connect terminals that are rated for solderability.

  Now I am down to 42 options and most of these parts would work for my customer’s application, however there are some features that we can narrow for preference as well.

  Some of these are Actuator Color, Actuator Type(Shape), Actuator Markings, and Illumination. While these will not functionally make a difference, they can aesthetically make a difference. Therefore, I wait on these until the end to eliminate these options from my search. Many customers need a replacement part to get their equipment working and if there are options that are aesthetics only we look at that last.

  Using these steps, I could narrow my customer’s options from 10,000 down to 5 and I offered the customer a rocker switch EG1529-ND 13 that met all his requirements.

  Conclusion:

  While my search example was very specific, the actions taken will work for almost all the switches we sell with some minor changes. Toggle switches will have actuator lengths and shapes.


  RenhotecIC is an electronic conponents store online, and we provide retail and customized services. Various USB Type C Connector are there. All order will be free shipped over $100. We Offer many kinds of electronic connectors, RF coaxial connectors, adapters and USB connector to satisfy your different requirement and application with High quality insurance.

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