1 or 2 dedicated 120VAC circuits for my CNC?

No eBay APP ID and/or Cert ID defined in Kunena configurationNo eBay APP ID and/or Cert ID defined in Kunena configurationI had no idea AD was out of stock on so much.  This supply chain thing is getting annoying.

RELAY
Here's a good alternate:



Omron makes good stuff, and the seller has 10 of them.

Or you could use the SSR for the router recepticle now that you've got the estop-controlled contactor supplying the 120vac.  The SSR isn't as dodgy when big-brother contactor is holding all the cards.image missing /media/kunena/emoticons/wink.png

FUSE HOLDER
The type/size doesn't matter, but the midget fuses are signficantly more expensive than 5x20's.  Or you can just use DIN breakers.

Here's a phoenix contact version:


CONTACTOR/RELAY
Note: contactors are relays.  They're just big, heavy, rated for high amps, and have a big old spring inside to break the connection. They also make an oddly satisfying 'thunk' when they energize.

The contactor supplies the 120v to the relay, and the relay (SSR or mechanical) lets LCNC turn the router on/off.  The contactor is just there to break the 120vac to everything in case of an e-stop.

If you wired the router receptical directly to the contactor, you - the human - have to turn the router spindle on/off manually even during an estop event.

You could connect the router relay (SSR or mechanical) directly to the incoming 120vac line power, but then the estop circuit wouldn't shut it off.

I figured you wanted the best of both worlds: LCNC can turn the spindle on/off, and the estop circuit will kill both the drive power and the router motor even if LCNC is trying to spin it up (it shouldn't, but there I go again not trusting computers).  In addition, you - human - can always turn the router off by switching it off on the router itself.

And no... if you turn the SSR/relay on/off, it does nothing to the contactor.  Note that there are TWO 120vac 'hot' lines going through the contactor.  One goes to the 60vdc PSU, the other goes to the input side of the SSR/relay.

You're using the contactor contacts (ha!) like a couple of SPST relays tied together.  You could, in fact, use two single-pole contactors both tied to the same estop circuit, but 1 and 2-pole DIN-rail contactors are somewhat rare.

ARRGH Can't edit the last post

DISREGARD THIS PART:
If you wired the router receptical directly to the contactor, you - the human - have to turn the router spindle on/off manually even during an estop event.

That's late-night brain fade.  Of course the router recepticle would turn off if the contactor were de-energized.  Duh.

Carry on...
 

spumco wrote:

You could connect the router relay (SSR or mechanical) directly to the incoming 120vac line power, but then the estop circuit wouldn't shut it off.

But the E-stop button when pressed breaks the signal going to the digital input on the Mesa board. When this happens can't LCNC turn off the 24V output to the router relay, killing power to the receptacle as well? And then the opposite once the E-stop circuit is reset? Much like the driver enable SSR.

I think I get the rest of what you said. Thanks for all the explanations. Big help!I have been putting together my parts list to run my 30A circuit and it dawned on me that I was told to use GFCI's for the outlets the CNC are plugged into. Now that I am running a 30A line, I do not see any 30A 120V GFCI receptacles. What do others do in this situation?
 It looks like the Omron relay (LY2N-D2) you linked to is only 10A. The socket that it is plugged into is rated up to 15A. This would work for my DC to DC circuits but I feel that I need at least a 15A for the DC to AC circuit (router).I found the spec sheet for the Omron LY series relays. I was able to determine that LY2's are DPDT and the LY1's are SPDT. But when I went to figure out the ratings it gets a little confusing.  The chart below shows resistive and inductive ratings under the Rated Load for both. BUT then they show a Carry Current and a Max Operating Current that is the same rating for both resistive and inductive. Do I go off the Rated Load? If so, then none of the Omron's will work for my router circuit.
 

Anyway I went ahead and ordered 2 of the LY2N-D2's with the 15A sockets for the DC to DC circuit. I then ordered one of the AutomationDirect 15A relays you mentioned for the DC to AC router relay, and will use the extra base. That will give me a spare LY2N-D2 for the DC to DC circuit.

I think I am close to ordering the rest of the components. Thanks

But the E-stop button when pressed breaks the signal going to the digital input on the Mesa board. When this happens can't LCNC turn off the 24V output to the router relay, killing power to the receptacle as well? And then the opposite once the E-stop circuit is reset? Much like the driver enable SSR.

Correct... and this is where we get in to opinions & preferences.  If the router relay is fed from direct line voltage and not through the contactor, if LCNC throws up (or the SSR fails closed) the router won't turn off.

Remember earlier when I said 'belt and suspenders'? My opinion is that a human should be able to turn off all motion and meat-cutting equipment without relying exclusively on software or software-controlled hardware.  LCNC is stable, and there are plenty of peoply who rely on software (LCNC or otherwise) for safety stuff.  I dont, and that's why I've suggested the scheme presented.

For a dedicated recepticle I wouldn't use a GFCI.  They trip when you least want it.

Sorry about the Omron... I zoomed in on the photo in the listing and I guess I misread it, or saw the base rating and confused it with the relay.

The router should be classified as an inductive load, which means they're rated for 7.5A in the DPDT config.  That's technically OK for the router (according to the router specs), but I suspect the contacts won't last a long time.

I've got one of the AD 782 DPDT relays switching a 12A vacuum on a router table, and another one switching a 10A(ish) coolant pump and they're doing fine after a couple of years of steady service.

Next step is playing tetris with all the components in the enclosure.  Leave yourself plenty of room if you can, otherwise you'll be using foreceps to get the wires in the component terminals.

Remember earlier when I said 'belt and suspenders'? My opinion is that a human should be able to turn off all motion and meat-cutting equipment without relying exclusively on software or software-controlled hardware.  LCNC is stable, and there are plenty of peoply who rely on software (LCNC or otherwise) for safety stuff.  I dont, and that's why I've suggested the scheme presented.

Yes I do remember that reference. And now it all makes sense. 

The router should be classified as an inductive load, which means they're rated for 7.5A in the DPDT config.  That's technically OK for the router (according to the router specs), but I suspect the contacts won't last a long time.

Yeah I know that inductive motors can draw a lot more current at startup than their rated amps. During my research I read they can draw anywhere from 2-7 times the rated amps. My table saws and my dust collection motor have a hard time getting going on the 15A circuits, especially if anything else is drawing from the same circuit.

I've got one of the AD 782 DPDT relays switching a 12A vacuum on a router table, and another one switching a 10A(ish) coolant pump and they're doing fine after a couple of years of steady service. 

That reminds me, I would like to figure out a way to switch my dust collection OFF during a fault, E-stop, end of job, etc. I haven't thought through the logistics yet. I may want to have it turn on when the router comes on but not sure. There may be times when I don't want it on while running a job. Either way I would like to figure out how I can accomplish this. The dust collection unit is on the other side of the wall that the CNC is on. I have dust collection conduit running through the wall at the ceiling level above the CNC. I thought I could run 24V +/- from a digital out on the Mesa up the wall and attach it to the conduit and run it through the wall to the outlet that the collector is plugged into. I thought about just getting one of the IoT Power Strips and connect the 24V wires to it. I am sure this is not the cheapest way but definitely the quickest/easiest way.

Next step is playing tetris with all the components in the enclosure.  Leave yourself plenty of room if you can, otherwise you'll be using foreceps to get the wires in the component terminals.

That is my next step is laying it all out. I am pretty sure I have some room to breathe in my cabinet for now, but as I upgrade I am sure it will go quick.

 

So I plan to use 10AWG stranded wire (because I have it available) for all 120V circuits up to the PSU's. I then was planning to use 14AWG for everything (low voltage) from the PSU's on, except for the motor cables which will be 18AWG 4 conductor cable.

I am sure some of this is overkill. I also have a bunch of 20AWG wire on hand if there are any circuits that I can use it on. What gauge do you use and/or recommend for what circuits?