breaker, receptacle, plug for 3 hp dust collector

[Bob Riefer]

Hello and happy holidays!

My new (to me) Woodtek 3 hp dust collector comes with 14 awg pre-wired to the switch box, but without a plug installed. The previous owner had installed a 6-20 plug, which is same as I have had on my past two 3 hp table saws.

As a somewhat electrical-confused guy, I'm wondering....

My table saw (and now this dust collector) both have the same 6-20 plug, on the same size wire from switch box on the tool. Both plug into a 20 amp receptacle. Both receptacles use 10 gauge wire running back to the panel (about 25 feet away). Both have their own dedicated 2-pole 30 amp breakers. The run for the dust collector was done last week by our licensed electrician who reviewed the entire thing and recommended repeating the same approach as seen on the table saw. Both tools fire up every time without ever tripping the breaker, and the plugs are cool to touch even after hours of use (yes, I know this ain't very scientific).

My question is... I'm having trouble understanding 30 amp breaker vs. 20 amp receptacle and plug. Seems like everything would be 30 amp across the board... remote switches recommended for this unit accept the same 20 amp plug that I have. The manual and calls to manufacture provide vague answers at best. Forum discussions of this quickly evolve to a level that's above my head.

The reasons I care are... I want a remote switch for the DC, and the ones that fit the plug I have state "up to 2.5 HP"... so my plug will fit the remote receptacle, but my motor is over the stated HP rating. Huh? Also, I always worry about unsafe conditions.

Can someone help me understand the dynamics here in terms that my 12 year old daughter could understand? Seriously, keep it really basic please, I'm still recovering from too much egg nog

[Jim Becker]

The breaker protects the wire not the tool. Since you end device requires less than 30 amps, you can use 20 amp terminations with no issue. Since the circuit is setup for 30 amps and with 10 gage wire in the wall, should you need to use it for a 30 amp tool in the future, you can just change out the receptacle to a 30 amp version at that point and be good to go. 30 amp receptacles and plugs are more expensive and since you already have 20 amp plugs on the tools, it makes sense to have the receptacles match for now.

(What you shouldn't do is put 30 amp terminations on a 20 amp circuit)

[Jim Dwight]

breakers are normally sized to fit the wire as yours are. But it is also normal to make the switches and outlets also rated for the same current. In 110V, 20 amp outlets are different from 15 amp outlets, for instance.

The risk you run with a smaller outlet on the circuit would only occur if something overloaded the circuit. Your tools should not. But a bigger tool plugged into the outlet could. Breakers are meant to protect during unusual conditions - like a tool malfunction resulting in overload - and your breaker will not protect your outlet from an overload. Outlets can fail and cause fires.

I did not dig out the NEC, it is possible this is OK on a 220V circuit but I am sure it is not on 110V. I doubt it is OK on a 220V. Simplest solution would be a smaller breaker. They are pretty cheap. A breaker smaller than the wire can handles is no problem at all. Breaker should really reflect the smallest rated part of the system. That way is should trip before anything overheats and causes a fire.

Here is an old post on essentially the same subject: https://sawmillcreek.org/showthread.php?85128-Is-20-amp-outlet-on-30-amp-circuit-legal&p=860199

I learned that 20A and 30 amp plugs are different, I had forgotten that. But it also references a section of the NEC that reportedly says not to do it. But lots of people do not see a problem. I still think a 20 amp breaker is a smart thing to do.

[Ron Selzer]

You stated a licensed electrician reviewed and installed the new circuit that would be good enough for me.
As to the remote switch you probably are on or above the line where the switch will destruct with use.
I used current transformers on every circuit (table saw, wide belt sander, jointer, etc) I want to monitor to turn the dust collectors on via a contactor.
By the way my dust collectors are 20 amp receptacles on 30 amp contactor and breaker. Due to inrush current which is only at startup.
I do use a 30 amp receptacle and cord end on table saw, planer, and wide belt sander on 30 amp breakers.
Due to actual power draw during use, ends up being a judgement call based on past experiences.
I would trust your licensed electrician on this one.

[Bob Riefer]

Hmmm...

So Jim's reply above had me nodding my head, seemed sensible.

Then later, I see Ron saying that my electrician steered me straight, but that a remote switch that will work with my 20 amp plug / receptacle is borderline.

If electrician looked at wire from tool and decided 20 amp plug and receptacle are in order.... then why would a remote switch that accepts a 20 amp plug and plugs into a 20 amp receptacle be a potential issue? That is... if there's an issue for the remote switch (which seemingly has the same anatomy as the tool plug and wall receptacle... just combined into one unit) why no issue with plug/receptacle?

[Ron Selzer]

plug and receptacle will take more than rated load momentarily as long as it is not way over
electronics in the remote switch are going to be ruined if it goes over rated load momentarily (this is based on observations and experiences of over 40 years in construction and maintenance work.) plug and receptacles of both are going to survive, they are thick enough. The electronic traces and contacts are typically sized just big enough for rated load and will not survive startup overcurrents. Go ahead and try, then report back how long that remote start lasts. It might make it for multiple starts, maybe even multiple years all depending on actual startup current draw, how often started and how it dissipates the heat from each startup.
Very typical for a piece of equipment to require on the nameplate a breaker sized heavier than the rated wire ampacity to eliminate nuisance tripping on startup. Breaker still will trip if wire shorts.

[Bob Riefer]

Ahhh ok this helps me understand. Thank you!

[Rod Sheridan]

In Canada, the receptacle must have a current and voltage rating that matches the feeder.

The only exception to that is multiple 15 ampere receptacles on a 20 ampere circuit.

Motor circuits are allowed to have a larger rating if the motor will not start on the 100% rated breaker. I have only seen this allowed on dedicated motor circuits, not circuits with a receptacle where another device could be used.

As for #14AWG flexible cord, it can be rated at 18 amperes with 2 current carrying conductors.

As always, check with the AHJ.....Rod

[ray grundhoefer]

It is not code compliant to put a 20 amp rec on a 30 amp circuit

[Bob Riefer]

Well, I’m confused as ever now.....

[Art Mann]

I agree with Ray. 30A circuits should be connected to a 30A rated receptacle. Buy your plug and receptacle from Amazon and save some money over the big box stores. Alternately, you could replace the 30A breaker with a 20A breaker and call it a 20A circuit. In my new shop, I standardized on 30A circuits and twist lock receptacles for all 240VAC, whether 20A or 30A. I currently have no equipment that requires more than 30A so I can plug in any machine anywhere I have a 240VAC outlet.

[ray grundhoefer]

If you plug a smaller motor into a 30 amp circuit and do not have overload protection on the machine you run the risk of burning out the motor because it will not trip the breaker as it should normally. For example wlth a dull blade on a table saw that should draw 12 amps it will not trip the breaker till you hit about 25 or so for a while

[Bob Riefer]

I talked to another electrician last night at a new years party. He thought that swapping out the breakers for 2-pole 20 amp breakers was the best bet at this time.

His reasoning was that if both tools (previous to me owning them) were happily working with 20 amp plugs on 20 amp receptacles, then let's match the breaker to that setup. If the breakers start tripping, we'll quickly learn that upgrading to 30 amp breaker, receptacle, and plug are in order.

[Jim Becker]

No harm in that at all, Bob.

[Art Mann]

This is an illustration of how intuitive thinking can be very believable but not correct. This opinion is coming from an electrical engineer with over 30 years experience, part of it in overcurrent failure analysis. The purpose for limiting the current in house circuitry is to prevent fire. Nothing else. If you take a look at the behavior of a normal household breaker and compare it to the typical failure modes of a motor, you will see why. Breakers will sustain twice the rated current for a minute or so and 10 times the rated current for several seconds. They are designed that way to accommodate starting current. If you don't believe me, just download a trip curve from any manufacturer and study it a little while. Then read up on how long an electric motor will survive a locked rotor condition. By the time the breaker opens up, a motor with a locked rotor is probably already lost. On the other hand, if a motor develops an internal short, the breaker will open up just in time to let you know your motor has been destroyed. Modern motors have resettable internal thermal overload circuits that will protect a stalled motor by opening up long before the breaker opens. Of course, it is possible to destroy some saw motors by continuous overloading but that is a case of it being impossible to protect someone from being a total idiot.

If you plug a smaller motor into a 30 amp circuit and do not have overload protection on the machine you run the risk of burning out the motor because it will not trip the breaker as it should normally. For example wlth a dull blade on a table saw that should draw 12 amps it will not trip the breaker till you hit about 25 or so for a while

[Bob Riefer]

Hi Art - can you translate? I’m frozen. It seems I have the one machine in existence that cannot be safely plugged in without catastrophic failure of some sort or another... ;)

In other words .... what would you have me do at this point? I read all these threads that go way above most of our heads, and I think in the end most just plug it in and hope for the best.

[John Lifer]

Jim is correct. And there is NOTHING wrong with a 20 amp on a 30 amp circuit. Nothing at all. The breaker on the wall is there to protect the wiring and the house/shop from fire. NOT to protect a motor or an appliance if it happens to draw more current than it should. If this was the case, you would have to size every piece of equipment in your home to exactly what is on the wall as a breaker. If you limit what you can plug into the 20 amp outlet (on the 30 amp breaker) to what is 20 amps or under, you are totally within NEC. If you plug a 30 amp load with a 20 amp plug and 20 amp outlet together, you are looking for issues. Keep your load below the rating on the plugs/outlets and you are FINE

[John Lanciani]

Jim is correct. And there is NOTHING wrong with a 20 amp on a 30 amp circuit. Nothing at all. The breaker on the wall is there to protect the wiring and the house/shop from fire. NOT to protect a motor or an appliance if it happens to draw more current than it should. If this was the case, you would have to size every piece of equipment in your home to exactly what is on the wall as a breaker. If you limit what you can plug into the 20 amp outlet (on the 30 amp breaker) to what is 20 amps or under, you are totally within NEC. If you plug a 30 amp load with a 20 amp plug and 20 amp outlet together, you are looking for issues. Keep your load below the rating on the plugs/outlets and you are FINE

This post is 100% wrong.

NFPA 70 (2017) article 210.21(B)(1)reads as follows;
(1) Single receptacle on a branch circuit. A single receptacle installed on an individual branch circuit shall have an ampere rating not less than that of the branch circuit.

[Mike Cutler]

Hi Art - can you translate? I’m frozen. It seems I have the one machine in existence that cannot be safely plugged in without catastrophic failure of some sort or another... ;)

In other words .... what would you have me do at this point? I read all these threads that go way above most of our heads, and I think in the end most just plug it in and hope for the best.

Bob

You're wrapping yourself around the axle here. Plug your machines in and enjoy them. All the theoretical's here are just that, theoretical.
You have the correct sized breaker, the correct sized conductors, your receptacle does not exceed either breaker, or conductor ratings. it was installed by a license and inspected. That's a huge step forward over most of the questions like this that are asked here.
Neither the 3 HP motor, or the remote, is going to challenge the electrical installation as you have detailed it.
If it worries you to leave them plugged in when not in use, unplug them when not in use. Many,many, people do. Many also have "whole shop disconnects" to secure power to all the machines, and receptacles, when not in use.Leaving only lighting.
Enjoy your shop. You're on good solid "ground". ;)

[Rod Sheridan]

Bob

You're wrapping yourself around the axle here. Plug your machines in and enjoy them. All the theoretical's here are just that, theoretical.
You have the correct sized breaker, the correct sized conductors, your receptacle does not exceed either breaker, or conductor ratings. it was installed by a license and inspected. That's a huge step forward over most of the questions like this that are asked here.
Neither the 3 HP motor, or the remote, is going to challenge the electrical installation as you have detailed it.
If it worries you to leave them plugged in when not in use, unplug them when not in use. Many,many, people do. Many also have "whole shop disconnects" to secure power to all the machines, and receptacles, when not in use.Leaving only lighting.
Enjoy your shop. You're on good solid "ground". ;)

Happy New Year Mike.

Maybe I missed something however I was under the impression that the OP has a 20 ampere receptacle on a 30 ampere circuit?

Regards, Rod

[ChrisA Edwards]

This is 100% wrong. NFPA 70 (2017) article 210.21(B)(1)reads as follows;
(1) Single receptacle on a branch circuit. A single receptacle installed on an individual branch circuit shall have an ampere rating not less than that of the branch circuit.

I think you have it backwards, my reading of that is don't wire a 15A socket (receptacle) in to a branch that's rated or supplied by a higher rated breaker, such as 20A or 30A.

[John Lanciani]

I think you have it backwards, my reading of that is don't wire a 15A socket (receptacle) in to a branch that's rated or supplied by a 20A breaker.

OP has a 20 amp receptacle on a 30 amp circuit. The receptacle has an ampere rating (20a) less than the branch circuit rating (30a) and thus is disallowed.

The receptacle is part of the branch circuit and must be sized accordingly.

[ChrisA Edwards]

OP has a 20 amp receptacle on a 30 amp circuit. The receptacle has an ampere rating (20a) less than the branch circuit rating (30a) and thus is disallowed.

The receptacle is part of the branch circuit and must be sized accordingly.

I agree with you here, but my response was to your response where you quoted John Lifer and started out by stating "This is 100% wrong".


https://sawmillcreek.org/images/misc/quote_icon.png Originally Posted by John Liferhttps://sawmillcreek.org/images/buttons/viewpost-right.png (https://sawmillcreek.org/showthread.php?p=2978390#post2978390)Jim is correct. And there is NOTHING wrong with a 20 amp on a 30 amp circuit. Nothing at all. The breaker on the wall is there to protect the wiring and the house/shop from fire. NOT to protect a motor or an appliance if it happens to draw more current than it should. If this was the case, you would have to size every piece of equipment in your home to exactly what is on the wall as a breaker. If you limit what you can plug into the 20 amp outlet (on the 30 amp breaker) to what is 20 amps or under, you are totally within NEC. If you plug a 30 amp load with a 20 amp plug and 20 amp outlet together, you are looking for issues. Keep your load below the rating on the plugs/outlets and you are FINE





This is 100% wrong. NFPA 70 (2017) article 210.21(B)(1)reads as follows;
(1) Single receptacle on a branch circuit. A single receptacle installed on an individual branch circuit shall have an ampere rating not less than that of the branch circuit.



All's good.

[John Lanciani]

I agree with you here, but my response was to your response where you quoted John Lifer and started out by stating "This is 100% wrong".



All's good.


Gotcha. I was referring to the poster I quoted saying what he wrote was incorrect.

[mike stenson]

I talked to another electrician last night at a new years party. He thought that swapping out the breakers for 2-pole 20 amp breakers was the best bet at this time.

His reasoning was that if both tools (previous to me owning them) were happily working with 20 amp plugs on 20 amp receptacles, then let's match the breaker to that setup. If the breakers start tripping, we'll quickly learn that upgrading to 30 amp breaker, receptacle, and plug are in order.

I agree with this, for the reasons Art mentioned. FWIW, I had both a 3hp saw and dust collector on the same circuit for years without an issue. They're actually never starting at the same time anyway.

[Bob Riefer]

:-) Thanks everyone for helping me.

Here's my final plan of attack:

Step 1: I emailed Woodtek (maker of my dust collector) and asked a very clear/direct question... Given that 10 gauge wire has been run to a dedicated location for just this piece of equipment.... do you recommend 20 amp 2-pole breaker with 20 amp receptacle and 20 amp plug? or 30 amp 2-pole breaker with 30 amp recept and plug?

Step 2: Sent same question to Grizzly (maker of my table saw).

Step 2: Based on their replies, I'll do make any needed adjustments and be DONE! LOL

[Art Mann]

The only problem I see with your installation is that a 30A circuit should always be paired with a 30A wall outlet. If it isn't, you introduce the possibility that someone will run 30A through the 20A receptacle and cause it to overheat. As long as you don't do that, you are fine (if not strictly code compliant). I have seen instances where somebody used a 3 for one adapter rated for 5 or 10 amps to power a 15 or 20 amp tool and the adapter melted. It is the same sort of problem that could happen here.

I went through the explanation about motors with various faults because people need to know that a breaker is not designed to protect anything beyond the wall plug. If you stall a motor rated for say 16 full load amps, the motor will either be protected by its own internal thermal overload breaker or the motor will probably burn up regardless of the breaker size.


Hi Art - can you translate? I’m frozen. It seems I have the one machine in existence that cannot be safely plugged in without catastrophic failure of some sort or another... ;)

In other words .... what would you have me do at this point? I read all these threads that go way above most of our heads, and I think in the end most just plug it in and hope for the best.

[Mike Cutler]

Happy New Year Mike.

Maybe I missed something however I was under the impression that the OP has a 20 ampere receptacle on a 30 ampere circuit?

Regards, Rod

Rod

I believe that is correct.
We do not know the total picture, What version of the code he was inspected to, or had to adhere to? Were there any exceptions?
He had his installation done by a licensed electrician. It was inspected. He should be good to go.

The discussion about having a 20 amp receptacle on a 30 amp breaker is somewhat academic. I'll agree to the single receptacle requirement, but there is not one thing wrong with having a receptacle installed on a circuit with a lower rating than the breaker. There are millions of them installed that way in the US. I installed hundred and hundreds of 120 vac, 15 amp duplex receptacles, on 20 amp breakers with 12/2 wire, while I was working toward my license in the 80's. Every one of them passed inspection.
If you have a 240/30 amp breaker, and in some hypothetical scenario, the 240/20 amp load plugged into a 240/20 amp receptacle, on that 240/30 amp circuit, somehow sees more than 20 amps, but less than 30 amps, there is not one single difference electrically if it's plugged into a 30 amp receptacle, or a 20 amp receptacle at that point. I absolutely guarantee that a 240/20 amp duplex receptacle can take 30 amps for a given period of time. How it can be postulated for the theoretical value greater than 20amps but less than 30amps is a stretch. No breaker/receptacle combination is designed to protect against that fault scenario.
The point about code compliance for a single receptacle on a branch circuit is valid, but that is all. For what ever reason though, he passed inspection. Let's all stop scaring the poor guy with hypothetical scenarios that are improbable, and let him enjoy his time and machines.

[Art Mann]

So, what you are saying is that a 20A wall plug is functionally identical to a 30A wall plug and that either should handle a 30A load on a regular basis. That is just ridiculous. Perhaps you are saying that everyone who uses a 20A wall outlet will verify that the load is not greater than 20A. That is also ridiculous. You seem to think that load currents in the range of 20 to 30 amps is unusual but in my observation, that is the norm in most advanced hobby and professional woodshops with 240VAC equipment. There is a reason why the National Electrical Code requires wall outlets to be sized according to the capacity of the breaker in the circuit. Someone has already referenced the applicable paragraph in this thread. The code was created under the assumption that people buy and sell homes and new owners may not be aware of any usage restrictions on existing wall outlets.

You can guarantee that a 20A circuit will take 30A "for a given period of time" and I wouldn't disagree, but what we are talking about is continuous usage. Perhaps what you should do is rig up a 30A circuit and load it to 30A through a 20A outlet in a safe environment and see what happens. You will need minutes, not seconds, to see the outcome. Actually, with all your experience, I am surprised that you haven't already encountered melted plastic from overloaded outlets.

[Mike Cutler]

Art
I respectfully disagree. The lugs in that 20 amp receptacle will take more than the current carrying capability of the conductors. Pass and Seymour, Crouse Hinds and Seimens will back that info up. The plastic insulator material is no different.
And I have done some informal, and formal, destructive testing on breakers, and receptacles as part of receipt inspection for electrical components used in nuclear qualified environments. I used to test fuses up to 5000amps. I've blown up breakers, melted them in place, started fires with them. All in a lab. Sometimes for fun, just to see how much something would take, but generally not. I don't do it any longer.
"So, what you are saying is that a 20A wall plug is functionally identical to a 30A wall plug and that either should handle a 30A load on a regular basis."

No, what I am saying is that in this given instance, with the given variables involved, there is no electrical difference.


The discussion wasn't centered around a load that was "expected" to be greater than 20 amps nominally, but some type of a failure/fault that would result in a condition greater than 240/20amps, but less than 240/30amps, with a 3HP motor. That is what I am referring to. If you know that your nominal amperage under load with no faults will be greater than 20 amps, then yes, there should be a 30 amp plug and receptacle. That isn't the case with this discussion.
The original question was whether or not to plug in a remote DC starter, rated at 20 amps, into a 20 amp receptacle, on a 30 amp breaker protected circuit.

Debate is always welcome and there is an opportunity for everyone to learn. In this instance though, the installation was installed by a licensed electrician. The work was inspected and signed off, and a 3HP motor under nominal loads, with no internal faults, is not going to challenge that breaker, the conductors, or the receptacle.

I am not trying to be intentionally obtuse, or argumentetive.simply for arguments sake. I have been doing this type of work my entire working life,over 43 years.
In that time I have never seen a receptacle catch fire, or melt, in and of itself. They are robust pieces of equipment. Faults in them, and switches, are usually traced back to poor initial installation, dirt dust, debris ,and grease, that gather inside, inferior materials, and oxidation.
If you were to search back through all my posts dealing with shop electrical questions, I am conservative in my responses, and almost always advise a person to get a licensed electrician, and an inspection done. My personal belief is that most homeowners have no business going beyond resetting a breaker in the panel.
The code exists for some pretty damn good reasons.It's not all about Seimens and Pass Seymour trying to gain market share through code requirement changes.
Knowingly violating the NEC is stupid beyond reckless.

[ray grundhoefer]

However, if I as a licensed master electrician of 40 years, were to wire someone's shop with all 30 amp receptacles and tell them they can plug anything they want into it would be getting an angry phone call and bitched at when their saw burned up

[Art Mann]

In order for an electrical code to be effective, it needs to be applied in all cases rather than allowing changes because they are safe in a certain limited set of circumstances. At the beginning of this thread, me and anyone with any experience agreed that our original poster doesn't have a safety problem with his plug and receptacle. I even said so. That isn't the point.

[Bob Riefer]

Sorry to have stirred up such a debate! :-)

I heard back from both manufacturers. Grizzly wants 20 amp breaker/plug/receptacle for the G0691 and Woodtek wants 30 amp breaker/plug/receptacle. Off to the hardware store to grab what I need to make the adjustments to match these requirements.

Note.. while a licensed electrician wired my setup, my outbuilding is considered "agricultural accessory structure" in my township and does not get inspected... So, while an inspector didn't alert me to an issue, my spidey sense told me that his 30 amp breaker > 10 gauge wire > 20 amp receptacle setup wasn't right, hence my additional questions and research. (this was my first and last time using this particular electrician)

My new model going forward is to call the manufacturer for their recommendation anytime the manual is at all vague (which I find is often the case) and then match breaker, wire size, receptacle, and plug accordingly.

NEW QUESTION: I read on here someplace, but can't find it now, some instruction on how to setup remote switching for a 30 amp receptacle... I think it was a relay (or something like that) with a run of the mill light remote. My new cyclone setup places the on-switch at about 8.5 feet above ground, so I can just barely reach it.

[Tom M King]

I always thought that the whole thing about using 15 amp receptacles on 20 amp circuits was a very strange thing indeed. It was also covered by having 120v appliances that draw more than 15 amps to use a 20 amp plug, with one leg 90 degrees to a more common 120v plug, so that it could only be plugged into a 20 amp receptacle that can take that shape plug.

I use the remote switch that Woodworkers Supply sells, with several remote button placed in convenient spots around the shop. The first one stopped working a little after the first year. They sent me another one, that got here on the second day, and that one has been working for about ten years now, with multiple uses most days.

[Bob Riefer]

The one from woodworkers supply... does it accept a 6-30 plug? most that I'm finding will only accept 6-20

[Jim Becker]

NEW QUESTION: I read on here someplace, but can't find it now, some instruction on how to setup remote switching for a 30 amp receptacle... I think it was a relay (or something like that) with a run of the mill light remote. My new cyclone setup places the on-switch at about 8.5 feet above ground, so I can just barely reach it.

I's common to use a contactor (a type of relay) to switch a 240v circuit for things like a dust collection system. One side of the contactor is the switched load to the tool. The other side of the contactor is the "control" side. Energizing the control side "flips the switch" for the load side. Control is typically either low voltage or 120v. (Mine is 120v) That permits you to get creative with how you physically perform the switching...it can even be an inexpensive remote control setup if that's what you prefer. I personally use a centrally located wall switch for my dust collection system. The contactor you use must be rated for at least the amperage provision for your circuit. The control side is your choice. My setup is provisioned like this, but there are multiple ways to handle and my particular contactor is 30 amp on the load side.

https://zfxh5g.bn.files.1drv.com/y4mZS-zKt-6OmEpbIcG5h3VT6C0zYE0HdOIiNwVkbrJ2pAgWRaWtBkuCbWfq T12hrNjKWIFyzdkX1rtiS421WJ4WEhYaGTF51BsgIl_57f5qeC sCp9xgHJBKFqCl7OdP74qi_INCNY68M43iWkYpX8slEzL1vsDw 2xhFFYaXrdOPKU9ysQWlbvlMeBGee-0N2R4vC-N7K7zNurn7liDVS67Ig?width=660&height=380&cropmode=none

[Tom M King]

Looks like they've changed it slightly, by looks, but mine is over ten years old. I think the yellow cover is the same. The plug that came built onto the DC power cord plugged into it, but I haven't looked at those plugs for ten years, so couldn't tell you anything about them. I think I changed the plug on the controller, but I can't remember what came on it, since I use twist-locks on all my 240v supply cords.

It's hung on the DC since the day we brought them home, so power source coming to it doesn't have to be remotely controlled.

I expect mine is the same one as this. I ordered several of the spare controllers.
https://woodworker.com/220v-dust-collector-switch-with-remote-mssu-172-847.asp

edited to add: If you set up a Pro Account with them, you get a pretty good discount on everything, and they have a separate website for pros. I like dealing with them because they're close to me, knowledgeable, helpful, and pleasant to deal with.