Electronics for New Machine + Chinese Spindle + VFD

[mturneruk]

Thanks Jazz

I am after simple and safe!
I understand how to wire the steppers. Just not 100% on the e-stop, additional fuses you mentioned or grounding.

2 x chassis power connectors (plugging into 2 plugs).
1 x EMI Filter on VFD Supply.
1 x VFD

1 x 48v Power supply
4 x stepper drivers
1 x UC300 USb motion controller
1 x KK01 Breakout board

1 x Estop
2 x 48v Fans

That's it.

[dodgygeeza]

The Estop should ideally be wired to an emergency relay, that will cut off the AC going to the 48V power supply and also the VFD.
It will also send a signal to the Bob that the Estop has been activated.

Connecting the Estop to the BOB and having your software control the Estop is a no no.

Thanks Jazz

I am after simple and safe!
I understand how to wire the steppers. Just not 100% on the e-stop, additional fuses you mentioned or grounding.

2 x chassis power connectors (plugging into 2 plugs).
1 x EMI Filter on VFD Supply.
1 x VFD

1 x 48v Power supply
4 x stepper drivers
1 x UC300 USb motion controller
1 x KK01 Breakout board

1 x Estop
2 x 48v Fans

That's it.

[JAZZCNC]

I am after simple and safe!
I understand how to wire the steppers. Just not 100% on the e-stop, additional fuses you mentioned or grounding.

Ok but you will need a few more bits.! . . . Nothing expensive but important to have. Momentery Reset Button and Some Relays. Plus if you want a best noise immunity then a 24V PSU.
I also suggest you buy a 5V PSU and power the Uc300 and KK01 from this and don't rely on USB to provide power. This will give you a much more stable system.

The VFD doesn't actually need to be pluged into another plug either if you don't want. I think your probably doing this because of something I said before but miss understood what I meant.?
When I said ideally Run the VFD on It's own Mains Line. I ment on separate Ring Main line not Different Plug line. All your sockets in the room and possibly house will run off the same Ring Main line so doesn't really matter if in same wall socket or across the room in another socket any noise will transfer to/from the VFD to other devices if bad.
Often this isn't possible or practical and why I said "Ideally" so in your case if you like you can just run from one plug socket. Then we Fuse them separate in the case.

This is what others are trying to tell you in that by the time you have put in these extra Fuses, relays etc which are minimum and needed for a truely safe system then you probably won't have enough room.!!
Also Don't let anyone tell you that Software driven E-stop system is safe and you don't need relays etc because it isn't and they are idiots to run without it for what little it costs to do right.

[njhussey]

Martin, don't underestimate how much more powerful this machine will be compared to your last one. When I built my machine I had it upright on it's end whilst I was attaching the Ali base. Whilst it was there I stood on the gantry and just like unscrewing a bottle top was able to turn the ballscrew and lift my weight (19.5 stone) with no effort at all. Now I know that if I accidentally get an arm/finger/leg(!!??) stuck/trapped whilst trying to hold something down (I know, I know, I know you shouldn't do it but.....) then I know for sure that if I press the E-stop I want it to stop dead 100% guaranteed...not be reliant on software to do it for me....

It all comes down to what you want to do safety wise really, have you given any thought to what you want the machine to do in the event of a brown trouser moment? As Dean says, for another £30 or £40 you can have a much safer system.

[mturneruk]

Here's what I have so far...

Plan is to put 2 50mm fans in the top of the case which will blow air directly onto the drivers / VFD into the case and out through the side / bottom vents.
I have mounted the control panel from the VFD on the front of the case.
I may leave the front cover of the VFD to allow more air into it.

This case is easy to work on as you can detach panels and put them back as required.
I wish it was a bit bigger, but as long as you think I wont suffer from EMI issues, then hopefully i will get away with it.
You may of course completely disagree.



Cheers
Martin

[mturneruk]

Thanks again for your help chaps.

It seems sensible to have the whole system shut down when e-stop is pressed. I would agree that it's a basic safety requirement.
So the next question is how to do that with a relay?

Jazz.
5v transformer in the box sounds sensible. I should be able to get a very small one. This could also possible run the case fans instead of 48v.

I think I understand what your saying about having one plug socket.
I would love to use one socket, but I was told to use 2 plugs by someone else at CNC4YOU so as not overload the wall socket. I thought 13A was the max?
Isn't the VFD using 8amps ish and the steppers / 600w power supply using a load more. E.g. Taking the load over what you can pull from a standard house socket?

EDIT : Can anyone confirm how many amps should be allowed for VFD driving spindle + 600 watt power supply driving stepper motors?

Obviously it's confusing on the forums, cause you have a load of guys talking about 3 phase and it's hard to tell what's what.
I thought I knew what i was doing. Obviously not.

If I have to scrap the case and get / make a bigger one I will (Or i might just take the VFD out into it's own box), but it would be nice to get it all in one.

Cheers
Martin

[Clive S]

Also have you thought about sucking all the dust into the control box

[mturneruk]

Thanks Clive.

Yes. It's not to bad as I have an extractor. Bear in mind this is a hobby machine, it's not going to be running all the time.
I hoover up as i go along as well.

Cheers

[njhussey]

Thanks again for your help chaps.

It seems sensible to have the whole system shut down when e-stop is pressed. I would agree that it's a basic safety requirement.
So the next question is how to do that with a relay?

Jazz.
5v transformer in the box sounds sensible. I should be able to get a very small one. This could also possible run the case fans instead of 48v.

I think I understand what your saying about having one plug socket.
I would love to use one socket, but I was told to use 2 plugs by someone else at CNC4YOU so as not overload the wall socket. I thought 13A was the max?
Isn't the VFD using 8amps ish and the steppers / 600w power supply using a load more. E.g. Taking the load over what you can pull from a standard house socket?

EDIT : Can anyone confirm how many amps should be allowed for VFD driving spindle + 600 watt power supply driving stepper motors?

Obviously it's confusing on the forums, cause you have a load of guys talking about 3 phase and it's hard to tell what's what.
I thought I knew what i was doing. Obviously not.

If I have to scrap the case and get / make a bigger one I will (Or i might just take the VFD out into it's own box), but it would be nice to get it all in one.

Cheers
Martin

I run my 2.2kW VFD on a 13A plug, same for my CNC router which powers the driver PSU (gives 72V DC) and the 230V AC driver I have for my Nema 34 motor.....they're on the same circuit.

I'm sure Jazz will come back with a wiring diagram shortly....I'm on my mobile whilst cutting stuff on my machine!!! In essence if you get a 24V (DIN rail mounted) PSU (1.5A or there abouts) and take the +ve from it through the E_stops and into a relay (take the -VE to the relay too but direct), when you hit the E-stop button it cuts power to the relay. You wire your mains through the relay contacts (NO) so that when it drops the power to the relay (E-stop) it cuts the power (the contacts open as no power to the relay) to the drivers etc. You can then get 24V fans for your case and supply them from this PSU as well! I suggest 24V as it's pretty noise resistant so good for safety circuits.

[mturneruk]

OK.... Thanks Neil.

Do you run your whole system from one physical plug socket or 2 - E.g. One for VFD and one for CNC ?

Why can i not use a 10Amp mains emergency stop button which cuts power in the AC mains line, thus doing away with the relay, transformer and all associated wiring....
e.g. Like this...

I want to keep things simple.
I really like the idea of having one physical kettle lead plug into my box, but I need to understand how many amps a VFD on full chat + 600Watt PSU driving stepper motor drivers will pull.
I have done some more research and a standard household plug socket is 13A max.

One things for sure is I need to check my consumer unit and understand my ring main better. I don't know what ring it's on or what else it's driving. Will do tomorrow.