Shopbot in makerspace - relocate switch

[whateg01]

I don't think this really falls under any electrical code but maybe it does. The makerspace has a shopbot. When it was first bought, it made sense to assemble it like it is, but it's been through a move and a couple shop reorganizations. Where it's living now has the main switch at the worst possible spot on the back where it's a pain to get to. I plan to move it to the front of the machine as well as add an e-stop.

The wiring and drives are housed in an electrical box with a 4x4 off to one side housing the main switch. I'll just put a blank cover on the 4x4 and run wires to the front where I'll add another 4x4. Should I just use some sjoow for this? Or should I run conduit from one corner to the opposite where the switch will now reside?

 

[PCustoms]

Pics?

 

[whateg01]

I won't be back in Wichita until this evening. Gotta finish the drive home from St Louis.

 

[Shiftless]

Pictures would be good. But if that is what I think it is, I’d say that a round black cord held down with some screwed in or glued on clips would be more than adequate for relocating a switch on a table top CNC machine.

 

[cvairwerks]

Except their ShopBot is a 4'x8' capacity machine.....a bit bigger than the average tabletop.

 

[mike93lx]

I would probably run liquidtite instead of cord

 

[LXCam]

If you really want to be code compliant you can use type MTW multi conductor cord. Personally, I’m with Mike on using sealtight.

 

[whateg01]

Is that just because it's flexible so easier to work with than rigid conduit? From that, I take it that code does say I should use conduit of some sort vs cord?

 

[PCustoms]

Is that just because it's flexible so easier to work with than rigid conduit? From that, I take it that code does say I should use conduit of some sort vs cord?

Code doesn't say anything as this isn't building wiring

 

[LXCam]

You need to decide how prone this would be to physical damage and or the environmental requirements such as explosion proof, etc. I don’t know what type of equipment this is but if it’s within a wood shop you could be required to meet installation standards as defined by class III, division 2.

 

[PCustoms]

installation standards as defined by class III, division 2.

Of what?

 

[LXCam]

Of what?

NEC class III division 2 code requirements.

 

[PCustoms]

NEC class III division 2 code requirements.

I don't think that would apply, but even if it does, since when does NEC cover the equipment side wiring?

 

[LXCam]

I don't think that would apply, but even if it does, since when does NEC cover the equipment side wiring?

NEC article 670
NFPA 79

Anything and everything electrical is covered by code. Even class II division wiring can get detailed when applicable to life safety requirements.

 

[whateg01]

You need to decide how prone this would be to physical damage and or the environmental requirements such as explosion proof, etc. I don’t know what type of equipment this is but if it’s within a wood shop you could be required to meet installation standards as defined by class III, division 2.

The plan is to stuff it underneath where damage isn't likely. Is sawdust an explosion hazard? I don't think it's considered to be.

 

[Steve from Socal]

Not familar with the machine in question but pics on the net show a pendant with a power and e-stop on a cord/cable. My Komo router has the controls on a stand with sealtight to the machine, laying on the ground.

 

[whateg01]

Not familar with the machine in question but pics on the net show a pendant with a power and e-stop on a cord/cable. My Komo router has the controls on a stand with sealtight to the machine, laying on the ground.

The way it's setup right now is similar to that komo as far as the controller being on a little stand with an umbilical. The current umbilical is just unprotected cord and rs232 cables. I'm working on improving that too. The current e-stop is also in that bundle of cords.

 

[whateg01]

NEC article 670
NFPA 79

Anything and everything electrical is covered by code. Even class II division wiring can get detailed when applicable to life safety requirements.

My understanding was that NEC doesn't cover internal wiring of equipment. That's why equipment often has wiring that's smaller than that in the wall for a given capacity. Is that wrong?

 

[LXCam]

The plan is to stuff it underneath where damage isn't likely. Is sawdust an explosion hazard? I don't think it's considered to be.

If all you're concerned about is physical damage, then I would suggest rigid conduit securely supported. You could either use it as a raceway as intended with flexible conduit to your control panel or as a pathway to route type MTW cord thru (just make sure you bush your extrance/exit points).

 

[LXCam]

My understanding was that NEC doesn't cover internal wiring of equipment. That's why equipment often has wiring that's smaller than that in the wall for a given capacity. Is that wrong?

Ya that's wrong. NEC article 430

Tell ya what guys, there's a bit of irony with the timing of this discussion. Controls and power has been my field for over 4 decades.


Today I'm putting together all the engineering schedules for a controls retrofit. And there just happens to be another 26 of these and double that for shithole cabinets and overhead jungle gym wiring acrobatics.

 

[Snapped-off]

Ya that's wrong. NEC article 430

Tell ya what guys, there's a bit of irony with the timing of this discussion. Controls and power has been my field for over 4 decades.


Today I'm putting together all the engineering schedules for a controls retrofit. And there just happens to be another 26 of these and double that for shithole cabinets and overhead jungle gym wiring acrobatics.

Do you ever deal with genetec?

 

[LXCam]

Do you ever deal with genetec?

Ya allll the time. Plus milestone and salient. We also use Bosch and viconet but I have no personal experience with it.

 

[TRWham]

My understanding was that NEC doesn't cover internal wiring of equipment. That's why equipment often has wiring that's smaller than that in the wall for a given capacity. Is that wrong?

It's not wrong if the equipment is listed (UL, ETL or some other NRTL). If you start modifying equipment in the field, then you may have a problem.

 

[whateg01]

It's not wrong if the equipment is listed (UL, ETL or some other NRTL). If you start modifying equipment in the field, then you may have a problem.

This isn't modifying something that was manufactured. My understanding is that the mechanical structure was purchased and then the controls stuffed in a box bolted to the end. I'm not sure what guidance there was at that time

 

[Firebrick43]

Industrial machines are covered under NFPA 79.

It’s not code (best practices) per sey but many insurance companies want to see it met. All the factories I have worked to those standards.

Sealtite is a good idea and RMC is even better if you want to go that route. And of course the more E stops the better.

 

[whateg01]

This definitely was a kit that "they" assembled with parts of it being homebrewed. I could just use speaker cord and maybe improve it a little. I thought there was a box. It's not. It's just a piece of plywood with a sheet of aluminum sort of screwed in place over it. At least they appear to have used a rubber grommet on the junction box with the existing switch.

 

[PCustoms]

This definitely was a kit that "they" assembled with parts of it being homebrewed. I could just use speaker cord and maybe improve it a little. I thought there was a box. It's not. It's just a piece of plywood with a sheet of aluminum sort of screwed in place over it. At least they appear to have used a rubber grommet on the junction box with the existing switch.

Does NEC/NFPA cover plywood backplanes?

That the switch you're moving? Seems obvious now that a bit of conduit is probably the way to go...

 

[Steve from Socal]

Yea,

That ain't quite what I would have expected. That DB-25 molded plug is going to be a hard one to fish through a conduit, maybe fold it sideways?

 

[whateg01]

Yea,

That ain't quite what I would have expected. That DB-25 molded plug is going to be a hard one to fish through a conduit, maybe fold it sideways?

My main concern is the 120v and 50v stuff. The low voltage wiring such as the parallel port can be in the open, I think. (Somebody will surely correct me if I'm wrong.)

 

[whateg01]

I just ordered a metal electrical box to stuff all of this into. I'll run EMC to the nearest accessible corner for the switch.

I'll 3D print a pass through for the wiring. That'll let me accommodate the larger cables and connectors.

 

[Firebrick43]

Yea,

That ain't quite what I would have expected. That DB-25 molded plug is going to be a hard one to fish through a conduit, maybe fold it sideways?

Cut it off and put a new one on. Db25 connector can be had for around $5. If you don’t have the correct crimpers the make solder versions of you don’t mind slumming it.

I have the crimpers that can crimpers the terminal and strain relief at the same time but unless you haunt eBay for a while the can be quite pricey.

The engineer pa09 are wonderfully pliers that are reasonably priced (but crimps in two steps)

Plus the crimp molex, jst, and other micro connectors

https://www.amazon.com/ENGINEER-AWG32-AWG20-Connectors-Oil-Resistant-PA-09/dp/B002AVVO7K/?tag=atomicindus08-20