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Thanks guys for the input, if it works that's good enough for me! [emoji4]. I have done a short video to explain my thoughts on how I'm going to set out the control cabinet and would be grateful of any comments before I start screwing things down...
https://youtu.be/0mJ4v-u51Ew
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Btw not sure why I said about 24v power going to drives. It doesn't.Quote:
Originally Posted by JoeHarris
Layout looks OK to me - I've only made one proper control box so far but I went through the same logic as you and it works OK.
Regarding one of your earlier comments - I decided against XLR connectors between the steppers and the control box and wired them direct to the drivers. Where the cables entered the control box there should be a strain relief gland then the outer braiding was twisted and soldered to an earth wire which went off to the star earth point on the DIN rail. The soldered joint was heat shrinked and looked quite neat. I think it was Dean who showed how he does it and I copied that.
The direct vs plug-in question comes down to whether it is actually of much benefit to be able to plug/unplug the motors from the control box and how often you would want to do that. There is the possibility of signal quality problems at the connector / poor connection over time - I understand that loosing the connection momentarily between driver and stepper whilst the are running can upset or damage the drivers for example. If you hard wire them and really want to disconnect a motor it is only a few minutes to loosen some screw terminals and feed the cable out.
I agree that in an ideal world, steppers would be hard-wired in one cable run back to the drivers. I have used XLR because I had originally wired the steppers back to a DIN terminal rail and it was a right pain to wire them in each time that the box came off the machine while I was building and testing. I had the connectors available from my previous machine so chose to use them. I'll probable unplug them all soon and dose them with a bit of switch-cleaner to try to keep them sweet.
You have a rather larger cabinet than I am using. Good idea! Mine is a bit cramped (hence the wiring/unwiring problem mentioned) and it would have been good to have had a bit more space. As it turned out, my control box just fits the available space on the underframe of the router so it came right in the end. The overall layout you are proposing looks fine to me. In particular, signal wires from the IP/M (good choice!) will run down the opposite side of the cabinet from mains wiring, and are also well away from the stepper cables. Since you have gone to the expense of the IP/M, I'm assuming that you will be using differential signal wires between IP/M and drivers? If you can get a bit of UTP cable, the twisted pairs in that make good interconnects for this purpose.
On the subject of wiring, are you planning to use wiring/bootlace ferrules? I came across these, fortunately shortly before I started putting my control box together, when someone here posted a link to a good offer on eBay or somesuch. You can get the crimp tool kits from AliExpress fairly cheaply (something like this). They make wiring easier and safer - no loose strands of wire waiting to short on neighbouring terminals, better clamping in screw terminals, etc.
It's all coming together - good luck with the wiring!
Thanks Guys. Yes I have some bootlace ferrules - used them on the power supply and they were great. Twisted pair sounds like a good idea although I hadn't thought of that tbh. I had intended to use some of the trirated cable. I have the connectors on order now so will probably use them but keep the cy a bit long so I can hard wire them if I have any problems. I've got 50m of cy so should have enough!!
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Do you guys just use cy cable between the spindle and the VFD? My cyc is 1mm2 is that going to be enough?
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Yes 1mm is enough that is rated about 11A and your 2.2kw is over 3 cables just one point if you are using a plug as normal on the spindle the make sure you fit a strain releaf on the cable so as not to let the cable move in the plug. If the plug comes loose or a cable breaks the vfd will go bang.:nightmare:Quote:
Originally Posted by JoeHarris
Thanks Clive - I don't want anything going bang!!Quote:
Originally Posted by Clive S
https://uploads.tapatalk-cdn.com/201...937eb28cfe.png
I have made a small amount of progress on the control panel and finally ordered the drivers...
https://youtu.be/hwv93Pd181U
Nice work Joe. You are doing all the right things and asking yourself the right kind of questions. Keep working through it and you'll have a box you can be proud of. Importantly you will be able to fault find or modify at a later date as you have kept it neat and have a wiring diagram to refer back to when you've forgotten what you did. I wish I had put wiring number tags on my cables and put labels on my diagram - something to think about