I have found that there are many times that I want to remove power from the controller. While this can be done by unplugging the main AC power cord, a power switch makes it much more convenient.

In addition to adding a power switch, I will be adding a 12v power source.  This will be used to power the cooling fans.


Wire the Switch

You will need a couple 15" wires to connect to the switch.  16 gauge will work fine.

The switch I used has screw terminals but feel free to solder them if you want.

I like to cover my switch terminals with some heat shrink.  

The power switch can be found on this page:

Additional Components


Connect the Power Leads

Pull main power lead (Line) from the terminal block.  In most cases its the black lead coming from the power cord.

Place one of the switch leads on this terminal block and attach the other to the cord lead you removed with a twist connector.

The twist connectors can be found on this page:

Additional Components



Prep the 12V Power Supply

I found these little gems on Amazon.  They are small dual power supplies.  Each one will provide both 12V and 5V for powering other items in the enclosure.

I use the 12V source to power the cooling fan. The 5v can be used to power a break out board.

They only cost about $13 and can be found on this page:

Additional Components

To prep the board for use, I attach 15" leads to the AC in side of the board.

I also add two, 2-pin headers to the two output terminals.


Attach the Board

I find a place to mount the board then mark the holes and use a 3/16" drill bit to drill four holes.

I insert a #6-32 x 1" machine screw through the bottom of the hole and secure with a #6 hex nut and lock washer.

The board is then slipped over the screws. Only one screw is needed to secure the board.  Make sure its one that does not have any exposed components that can get damaged with the #6 hex nut used to secure the board.


Connect AC to the Power Supply

I then connect to the AC input leads I added to the board to the terminal block as shown here.  

At this point you can add the terminal cap to the power terminal block.

Other Power Options

I have a ton of these little power boards, that I used to use with my early robot projects.

This particular one has a small LDO 12v regulator that I can wire up to the output of the 24V power supply I'm using on this particular build.