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View Full Version : Control box wiring: cables, terminals, connectors etc.



eurikain
07-11-2015, 03:44 PM
Hi everyone,

I am in the process of making my control box. It is made of:
- 4 x AM882
- cheap 5 axis BOB
- DIY linear PSU
- VFD

It all fits nicely inside an old computer box I've got. I am currently looking for an easy way to connect it all together. I have done a few researches and saw one control box where I really like the wiring: http://www.monkeyfx.co.uk/pictures/cnc/K2/controller2-sm.jpg

So, I have a few questions:

General questions:

What kind of crimp terminals would you recommend ? Where is the best place to find the ?
I have read on here that I can use 0.75mm2 cable. Is that alright ? Can 1mm2 do the job ?

Drivers to BOB:

Flexible PC wire (gotten from old PSUs), ferrule at both ends, and a male-female connector in the middle for easy wiring plug / unplug. The hard thing is that all PUL+, DIR+ and STEP+ are going to 5V+. There is only one 5V+ screw terminal on the BOB, so that's 3 to 1 wire per driver, and a total of 12 wires going into one screw terminal block.. there's just no way this is going to work.

Motors to control box:

GX16 4 pin connectors.

Limit switches to control box:

GX16 2 pin connectors

PSU to drivers:

On this picture (http://www.monkeyfx.co.uk/pictures/cnc/K2/controller2-sm.jpg) there is a sort of multiplexer terminal block. I don't know the correct technical term, but I think you see what I mean. Where can I get those ? Or what would be a good way to get a 2 to 8 pin terminal block ?

VFD to BOB:

Crimp terminals, single wire pin to pin.

Could you share your experience building control boxes and DOs and DON'Ts ?

Thanks a lot !

Cheers,

Clive S
07-11-2015, 05:07 PM
Drivers to BOB:

Flexible PC wire (gotten from old PSUs), ferrule at both ends, and a male-female connector in the middle for easy wiring plug / unplug. The hard thing is that all PUL-, DIR- and STEP- are going to enable. There is only one enable pin on the BOB, so that's 3 to 1 wire per driver, and a total of 112 wires going into one screw terminal block.. there's just no way this is going to work. Where do you get this info from? Have you a link to the BOB? Have you drawn a schematic of what you are trying to achieve ?
Do a search on the forum for control boxes.

eurikain
07-11-2015, 05:12 PM
Here is the BOB manual. It seems to me that there is only one enable pin. Otherwise you have to use the 4 pin serial connectors, which I have no idea where to get the matching males..

16475

Also, I have done a search on the forum, but the search engine is not so good. I haven't found a thread that explained that type of information :/ You know the forum better than I do ^^ I have had this search problem since I started using the forum. I mean, honestly, even using the advanced search with "control box" returns 20 pages of threads among which the first 3 pages haven't given me any clue...

I have a schematic diagram on its way, not ready yet. But wiring is not really my issue so far, as I understand quite clearly the big picture and have ready the AM882 manual, BOB manual, and the thread talking about the 2.2kw chinese spindles (so I got most of the info needed on that side). Once it's ready I will post it on here to get it checked by you guys.

Clive S
07-11-2015, 05:24 PM
Ok I don't see anywhere in the BOB manual that you connect all the pul, dir and step to the enable pin. So not sure where you are reading this.

eurikain
07-11-2015, 05:28 PM
Oh wait, that's right, sorry, I mean that all STEP+, DIR+, PUL+ are going to pin 5V+, which makes a total of 1 pin on BOB going to 12 terminals (3 on each driver). Excuse my mistake :) There are still 4 wires (on for each driver) going to 1 screw terminal, I don't think that can fit easily, looking at the size of the screw terminals.

Clive S
07-11-2015, 05:34 PM
You link all the +ve on the driver as you only need one wire to carry the +ve to the driver as it shows on the BOB manual page 3 Hope this helps

eurikain
07-11-2015, 05:55 PM
I see what you mean :) It does help ! I need wire splicers to split the 1 to 3 cable once close enough to the driver then, is that correct ?

Clive S
07-11-2015, 06:02 PM
I see what you mean :) It does help ! I need wire splicers to split the 1 to 3 cable once close enough to the driver then, is that correct ?No just connect the +ve to the first terminal then with a short link connect that terminal to the second and then the same for the third.

eurikain
07-11-2015, 06:22 PM
No power reduction will happen ? Weird, seems like a parallel connection to me, but that's where I am a total beginner :) Thanks for the advice !

Clive S
07-11-2015, 06:32 PM
No power reduction will happen ? Weird, seems like a parallel connection to me, but that's where I am a total beginner :) Thanks for the advice !It is a parallel connection as it would be if you connected all the cables to one terminal. As regards power reduction the driver signals are only in mA say about 10 so you can use very small dia wires Cat 5 is ideal

eurikain
07-11-2015, 07:34 PM
Awesome, thanks for the explanation ! Then that's perfect, my 4 pin Molex connectors will work like a charm :D Got them for free, they're great snap in connectors :)