2020 power distribution box

Last crawled date: 4 years, 2 months ago

Introduction
I have recently built an Anycubic Kossel Linear Plus, and decided that I needed some LEDs to illuminate the print bed (https://www.thingiverse.com/thing:2764599). Unfortunately there are no simple places to get access to 12v, unless I put wires under the Trigorilla's screw terminal block - not a good or safe solution).
My solution
I ended up by designing a small box similar to those I've installed on other printers, but this time a lot tidier and more universal in appeal. This can be fixed to 2020 profile in a convenient place using M3 T-nuts.
This box holds a piece of stripboard/veroboard that is 16 holes along the copper strips and 5 holes across. The board may need a bit of judicious filing along the long edge to make it fit. The circuit board is held in place by two M3 screws (I used short nylon screws) that go into tapped holes. You might to be able to use self-tapping screws of the right size, but I haven't tried that - you will also have to watch out for short-circuits if you use metal screws of any sort.
The board holds three strips of header pins, each 8 pins long, in black, red and white. Only the black and red strips are connected (-ve and +ve) - the third is used so that 3-pin headers can be used, with red to the central connector and black to one side; this means that it is hard to connect the circuit the wrong way around - it either works or it doesn't make a connection. Unless you try really hard to be silly you can not make a reversed connection (but it's not impossible).
PLEASE NOTE: this is only for low-current devices as stripboard has a very low current-carrying capacity. LEDs, small fans, etc, should be fine.
Connecting to 12 volts
I opened up the power supply on my Anycubic Kossel and found that there were 2 unused screw terminals available - very convenient! I crimped 2 fork terminals of the correct size onto some appropriate cable (actually 16A cable for use in car loom wiring), screwed them in place and threaded the cables through the sleeving before closing everything up again.
IMPORTANT: I you are not confident in working with power circuits then find a 12v supply elsewhere and leave the power supply cover untouched. There is mains wiring inside that cover - and obviously the power plug should be out when you do this work!
I would recommend that you fit a polarised 2-way connector just after the sleeving ends; I happened to have a few XT30 connectors so I used them, but any good connector would do the job.