3 Axis CNC router

**routercnc** · 27-04-2017

Originally Posted by JoeHarris

I think I've finished the power supply... haven't switched on yet as I want to look it over again with fresh eyes and make sure I haven't done anything dumb! Here she is:

Power in top right via the D curve mcb which will be din mounted and dc out from the lower terminal block. I have wired a 10k resistor between the dc terminals to drain the caps once powered. Any comments before I turn it on?!

If you got 50V in post 373 at the rectifier then so long as capacitors are correct way around then should work . . . Only one way to find out

**Neale** · 27-04-2017

Only comment (if you have a chance to make any small mods at this stage) is to add a few more sets of terminal contacts for the output, all wired in parallel. This allows you to run separate power feeds to each stepper driver, rather wiring them daisy-chain fashion, and it's easier than trying to stick three big wires in the same terminal. Not sure if it really make a difference in our class of machine but it is generally considered good practice not to share high-power connections between devices, and it's a lot easier if you have multiple terminals available. Might be able to put multiple spade terminals on each of your contacts, though?

**JoeHarris** · 27-04-2017

Originally Posted by Neale

Only comment (if you have a chance to make any small mods at this stage) is to add a few more sets of terminal contacts for the output, all wired in parallel. This allows you to run separate power feeds to each stepper driver, rather wiring them daisy-chain fashion, and it's easier than trying to stick three big wires in the same terminal. Not sure if it really make a difference in our class of machine but it is generally considered good practice not to share high-power connections between devices, and it's a lot easier if you have multiple terminals available. Might be able to put multiple spade terminals on each of your contacts, though?

Thanks Neale, The terminals are overkill in terms of size and will take two cables each but as I've shown on the circuit diagram the plan is to take one feed from the terminals on the power supply to some din terminal blocks with a jumper bar to provide as many as I need...

**Neale** · 27-04-2017

Sounds fine. My PSU was originally bought from Zapp, although I have now changed the transformer in it, but it came with three pairs of output terminals already. Then I fitted it in a control box with four stepper drivers...

Must confess that I didn't actually put a wiring diagram together for mine, just some sketches to work out roughly what was needed. Then I set to work with a pile of cable reels, big box of ferrules and crimping tool, and quite a lot of black coffee. Don't try this one at home

Still, it does seem to work OK.

**JoeHarris** · 27-04-2017

Originally Posted by Neale

Sounds fine. My PSU was originally bought from Zapp, although I have now changed the transformer in it, but it came with three pairs of output terminals already. Then I fitted it in a control box with four stepper drivers...

Must confess that I didn't actually put a wiring diagram together for mine, just some sketches to work out roughly what was needed. Then I set to work with a pile of cable reels, big box of ferrules and crimping tool, and quite a lot of black coffee. Don't try this one at home

Still, it does seem to work OK.

Ha yes I would definitely fail with that approach so well done!

Well I've plugged it in and...

It works! Hooray, my first functioning bit of electronics for this machine!