Electronics for New Machine + Chinese Spindle + VFD

[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.

[mturneruk]

Found some maths.... Not sure if it's right.

I (Amps) = P / V


So for my 48V power supply...
600 Watts / 48V = 12.5 Amps Potential...
Is that right. Something tells me it's more complicated than that..

[Clive S]

Found some maths.... Not sure if it's right.

I (Amps) = P / V


So for my 48V power supply...
600 Watts / 48V = 12.5 Amps Potential...
Is that right. Something tells me it's more complicated than that..

That is 12.5 A at 48 volts BUT you are using about 230V so 600/230 = about 2.6A

[mturneruk]

Ahhhh. Right. Thanks Clive.
That's better.

So lets say 3 amps from the PSU controlling stepper motors and i think i read 9 max from a VFD.. ?
So does that mean I could potentially run it all off one plug then with a 13a fuse?
Sorry for the dumbness on my behalf. I had to remind myself how a ground / fuse works earlier.

Getting there...

[Clive S]

Ahhhh. Right. Thanks Clive.
That's better.

So lets say 3 amps from the PSU controlling stepper motors and i think i read 9 max from a VFD.. ?
So does that mean I could potentially run it all off one plug then with a 13a fuse?
Sorry for the dumbness on my behalf. I had to remind myself how a ground / fuse works earlier.

Getting there...

I think you said that you read every word 5 times. It has been said several times that you can power your system from one plug. You really should take the advise from the good people on here all these questions have been asked lots of times.

[mturneruk]

Thanks !
Really getting somewhere now.

So it's decided that I need one power input into my enclosure and split it. Not listening to the bloke that told me I had to run two plugs any more.

So one side of the internal mains split will go to an EMI filter and then to the VFD.
The other side of the split will go directly to the 48V PSU.
One single all in one 10Amp chassis connector / fuse / power switch.
Easy. Job done.

Apart from Emergency stop.
So can anyone confirm why I can't just use an inline mains e-stop button. How does a relay do the job better ?

Thanks massively for your help.
Martin