220v Plug End Replacement for Equipment

Page 2 of 3  

snip

400amp service? Are you running an aluminum smelter?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

See my response to Doug.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
<snip>

Think 'short extension cord', external to the building wiring.
All of the 240v circuits were 30A, installed, by a licensed, bonded, insured electrical professional. Who installed a subpanel, with lockable master lockout switch.
Sorry if my inaccurate, or irregular use of the language caused confusion. It was not my intent.
Patriarch
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

No problem, it's what I thought you meant, but wanted to be sure.
It is an interesting idea and I like the concept. Is there a reason you didn't want to just replace the entire cord to the machine or at a minimum just the plug end as I proposed?
If you were going to use the equipment in areas that have different receptacles types, I think this is the best option. Given that I am trying to standardize on a receptacle type, it seems to me you are doing both sides when you would only need to do one.
Did you want to leave the original power cord and plug end in tact for warranty purposes?
Thanks,
David
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I didn't want to cut into a brand new machine, if unneeded. And this was a brand new saw, since I couldn't find a good used one at the time, and was pi$$ed at the old one.
And I deserved it. 2002 was a tough year.
Patriarch, glad that's over!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Patriarch wrote:

Love the caveat, and the pigtails idea. Both are great ideas. Used the pigtails before in boating to match shore power...
Some good things _do_ come from California -- see? :-)
--
Will
Occasional Techno-geek
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I installed receptacles with the configurations needed for the plugs on the tools that I have.

IMO, the twist-lock plugs are not really necessary. In fact, a twist-lock plug that is *not* fully twisted and locked is much *more* likely to fall out of its socket than is a standard plug. I've never observed any of my standard plugs to come out of their receptacles unexpectedly.

Entirely correct. However, it's flexibility that you don't need, and, if it's not done correctly, there is a potential hazard. If you're going to do this - and I wouldn't - you MUST use receptacles and plugs that are rated for the HIGHEST amperage circuit in the shop. To do otherwise would make it possible to, for example, plug a tool drawing 40A into a receptacle rated for only 20A, on a circuit that can safely carry only 30A.
And, of course, every time you buy a new piece of gear, you're going to have to change the plug on it.
What happens if you, sometime later, buy a piece of equipment with a higher amperage rating than anything you have now - and higher than anything you have a receptacle rated for? You'll need to install a new receptacle with the correct rating, and, perforce, a different configuration. And then your interchangeability is out the window, unless you replace all your plugs.

That will be no problem at all. If the equipment doesn't need the neutral, it doesn't need it. And if it does, it's there.
However, I think this is completely unnecessary. Not to say they don't exist, of course, but I haven't yet seen a piece of woodworking equipment that has both 120V and 240V loads, and it's hard for me to imagine one that would. On a range or a dryer, the neutral is needed because the heating elements are 240V, but the lights, timer, etc. are 120V. The electrical components of woodworking tools typically consist of a motor and a switch. A 240V motor has no need of a neutral.

I wouldn't do it. To sum up: - unnecessary expense and effort to replace multiple plugs - twist-locks are not needed (another unnecessary expense) - risk of fire if amp rating of receptacles not matched correctly to tools - no need for neutral on 240V tools (more unnecessary expense)
-- Regards, Doug Miller (alphageek at milmac dot com)
Nobody ever left footprints in the sands of time by sitting on his butt. And who wants to leave buttprints in the sands of time?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

Sounds like you dont move your equipment around much. I do based on space limitations. While a good portion of the circuits will be dedicated to specific equipment and I can match the receptacle to plug, some outlets are being installed with the expectation that several pieces of equipment will be used on them. Just as one would wire 20amp 110v circuits instead of 15amp to be able to power all 20amp and below 110v equipment, I plan to do the same with my 240v equipment. The rub comes in with the 240v receptacles and plugs is that they have different blade configurations depending on whether or not they are a 15amp, 20amp, or 30amp and beyond pieces of equipment.
I probably didn't make it clear before, but I plan to run 10/3 wire with ground from 30amp breakers for all my 30amp and below (multiple around the shop) connections. I plan to run 6/3 wire with ground from a 50 amp breakers to handle the equipment that runs at more than 30amps but less or equal to 50amps (one for the larger air compressor as Lew H recommended and an extra for other equipment that requires up to 50amps).
Given that most of the equipment runs on either 125v or 250v, I will have to replace the power cords anyway. This will allow me to go to a common plug and receptacle that gives me the flexibility to move my equipment around.

This is good input and why I asked the question originally. They are on the pricey side, but I wouldn't mide the expense if they were a better connection. Doesn't seem from your input that they are worth the extra expense.

My clarfication of what types of circuits I am installing on what type of wire above covers this.

Depending on the type of recpeptacle I decide is my standard, I might or might not have to make a change. Again, most of the 240v equipment I have purchased works on 120v and 240v, but they come wired for 120v. I would need to replace the cord anyway so the plug is a moot point then. The added time or cost for the plugs or cords is not that significant to me given the equipment generally runs in the just under $500 on the low end, so a $10 - $30 plug end or cord assembly doesn't seem to much to me.

Based on what I have currently for equipment, the fact that I have am installing a centrally located 50amp circuit, and my planned purchases in the forseeable future, I will be covered. If I do need something higher, I will install a circuit for that at the time. The subpanel or main panel will have the space and capacity I need.

This is what I thought, but wanted to be sure.

To me, it's cheap enough to run the 10/3 w/ ground and 6/3 w/ ground now so that in the event something does require it, I don't have to rerun circuits. I can always cap the neutral off in the receptacle box and install a receptacle that uses the 2 lives and the ground.

Thanks for your comments,
David
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I think you should go ahead and put 30A and 50A rated sockets on the 30A and 50A circuits respectively. Chose twist-lock or not as you see fit. Then just put matching plugs on the equipment as needed. If there is no nuetral on the machine, you just leave that one unconnected in the plug. Make sure you have a good ground connection. All of this is safe and legal. Just don't put a 30A plug on a greater than 30A machine. The two different rated sockets/plugs will not physically fit into each other so as long as you don't put the wrong plug on a piece of equipment you will have no problem.
Bill Ranck Blacksburg, Va.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Almost all of it's on wheels. Some of it stays put, some of it moves every time I use it. And there are a *lot* of receptacles in the shop. :-)

Right, but since you're presumably installing multiple receptacles *anyway*, it seems to be that it's a lot less trouble to install, say, six receptacles of three different configurations, than it is to install six receptacles of the same configuration, *and* change somewhere between one and five plugs on your machines.
Less expense, too, because (a) receptacles are usually cheaper than plugs, and (b) n receptacles clearly cost less than (n receptacles + n plugs).

Why do you have to replace power cords "anyway"? I'm not following you here.
-- Regards, Doug Miller (alphageek at milmac dot com)
Nobody ever left footprints in the sands of time by sitting on his butt. And who wants to leave buttprints in the sands of time?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

I will have 15 240v outlets in the workshop area. My original thought was to go with the twist lock outlets so I would have been replacing all of the equipment plugs anyway. Based on your comments that the Twist Lock P/R's are not really required and can fall out if not properly locked, I will need to assess what I am going to do. If I decide to go with a blade style plug and receptacles and your recommendation of switching them up to match the plugs, my equipment is tied to the locations of those outets. Another thought would be to install both receptacles in a double gang box.

Given that I am doing the work myself finishing our basement, the savings of not paying a contractor more than covers the cost of plugs for many different pieces of equipment IMO. My comfort level that I have quality easy to use connections to my equiment is worth the extra cost.

If I compare the cord on my 240v air compressor with that of other the equipment that is rated for 120v and 240v but prewired for 120v, the cable difference is significant. I understand that the size of the cord varies based on the amps required by the equipment, but since I will be switching the wiring out at the equipment to make it run on the 240v power, installing a better quality cord makes sense to me instead of just replacing the plug end (obviously where needed).
--

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

That's an awful lot. I don't have that many 120V receptacles in mine, and I haven't found there to be a problem.
[snip]

The part that I think you're missing here is that a tool draws *half* the current at 240V that it does at 120V. Thus, for any given tool, the cord needs to be heavier for 120V use than for 240V. Your 240V air compressor has a heavy duty cord because it draws a lot of current, not because it runs at 240V. There's no reason IMO to replace the cord: if it's heavy enough to carry the current the tool pulls at 120V, it's already *twice* as heavy as it needs to be to carry the current the tool will pull at 240V.
-- Regards, Doug Miller (alphageek at milmac dot com)
Nobody ever left footprints in the sands of time by sitting on his butt. And who wants to leave buttprints in the sands of time?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

Has more to do with the shape of the workspace than anything, not being the traditional rectangle shaped space.

bad example with the air compressor. A better example would be a comparison between my Delta dust collector and my Grizzly tablesaw. Both have 1.5hp motors, and both work fine, but the quality of the cord on the Delta is much nicer than my 12+ year old Grizzly. The general quality of some of the cords are not to my liking so if I have to replace the end to match a receptacle, I might as well upgrade the entire power cord.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Ah, I see. Of course, that's not an electrical issue. :-)
-- Regards, Doug Miller (alphageek at milmac dot com)
Nobody ever left footprints in the sands of time by sitting on his butt. And who wants to leave buttprints in the sands of time?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Fri, 22 Apr 2005 12:39:16 GMT, snipped-for-privacy@milmac.com (Doug Miller) wrote:
[snip]

What's a 20A receptacle doing on a circuit fused at 30A?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

enough to have _no_ confidence in the proposition that they don't happen.
-- Regards, Doug Miller (alphageek at milmac dot com)
Nobody ever left footprints in the sands of time by sitting on his butt. And who wants to leave buttprints in the sands of time?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

In engineering terminology, the technical description for that situation is "a mistake".
Such things _do_ happen in the real world. <wry grin>
Remember: "There is no such thing as a 'fool-proof' system. For any attempt at devising such a system there is a *sufficiently*determined* fool that is capable of breaking it."
The 'pigtail' system described _can_ be deployed "safely", *IF* you follow a few simple rules. 1) All the in-wall wiring, breakers, and receptacles are rated for the draw of the highest-powered piece of equipment to be used. 2) The breaker has a load rating that is no higher than the minimum of the wiring rating, or the receptacle rating. 3) The wall receptacle rating is no higher than the wiring rating. 4) the 'pigtails' *always* have an 'equipment-side' fitting that is rated no higher than that of the 'wall-side' fitting.
If rule #1 is followed religiously, then 'strictly speaking', rule #3 is not necessary. There is nothing 'unsafe' about using higher-rated connectors for a lower-rated circuit *AS*LONG*AS* the circuit rating is not exceeded. There is a risk that 'at a later date', something will be introduced that _does_ exceed the circuit rating, with 'unfortunate' effect. This potential "down the road" problem is avoided by using 'right-sized' connectors. :)
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
DL wrote:

<snip>
I did what you're proposing, and it works fine for me.
I bought a 3hp Unisaw, 2hp Rockwell planer and 1.5hp General jointer, all at estate sales. Each had a different 240V plug.
I put in a 30 amp breaker, 10 gauge wire and a 30 amp receptacle for this stuff. Eventually I'll probably put in more receptacles, but the jointer and planer tend to get moved each time I use them, so unplugging and plugging hasn't turned out to be too burdensome.
The saw came with a 30A twist-lock plug, so I standardized the other machines to that. I'd probably look for a lower cost option if it wasn't for already having a twist-lock.
The magnetic starters on the saw and jointer have overload protection built in and the planer has thermal protection on the motor. The jointer and planer could run on lower amp circuits, but, why bother putting in separate circuits just for them?
I've also got a 50 amp receptacle, but it's just for the welder.
I agree with others that running four wire circuits isn't necessary. If you decide to, just don't connect anything to the neutral wire lug in the plugs of 240V-only machines and you're fine.
In fact, before putting in a sub-panel, I had been running a cheater-cord (aka pigtail) that had a range cord and plug on one end and the twist-lock receptacle on the other. I didn't need a neutral, so just cut that lug off the plug. Disclaimer: you need to do two things if you try this: 1) understand that your range circuit is probably 40A, making your 30A receptical illegal, and, 2) have speeddial set to a nice restraunt if SWMBO comes home finding her stove unplugged one too many times.
Good luck,
Tim
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Here's what I did...I asked around as to what plug is the most common for 220v and installed electrical outlets that fit that plug. All my 220v tools have the same plug type and my shop has seven 220v. receptacles. I'd forget about the twist lock mechanism--the 220v plugs have enough friction that they stay in place. And when I need a new plug, there's one available in more than one store.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I think that is a good idea. Thanks for the comments.
David
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Related Threads

    HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.