How to extend a 220 cord from jointer ?
user780791_
| Posted in Power Tools and Machinery on
I have just ordered an 8″ jointer. It will come with a 6 ft cord, but I need another 5 ft to reach the 220 outlet in my shop. Apparently there is no such thing as a 220v extension cord ? Do I have to rewire a new cord at the motor ?
Also, the machine is 3 h.p. but the cord is only 14 gauge……I know little about electrical matters, but my table saw is 3 h.p. and it has a 10 gauge cord, so I have to wonder, but maybe I’m missing something.
Has anyone dealt with a similar issue and know the best way to solve this issue ?
Replies
The gauge of wire needed is a product of two things the Amperage of the load and the length of the cord. Due to something called voltage drop over longer runs of wire the amperage rises necessitating heavy wires on longer runs.
For your purposes I would guess your 3 hp jointer draws something around 10A (amperage loads are generally half at 240V compared to 120V) at 240V which is well within the range of a 6' long 14 gauge cord which is approved up to 15A for moderate lengths.
As to extending the cord it is always better to replace the cord rather than use an extension. Every plug/receptical connector increases resistance and subsequently amperage. In your case I would recommend a 10 GA. Cord but 12 GA. would be sufficient as well. Just be sure to get the proper NEMA plug and receptical for the amperage you need. I prefer locking plugs but that is up to you.
The 14 gauge wire is calculated for the very short cable they provide, it’s a way to reduce cost but will increase losses if used in longer length. I have replaced mine on 3 machines with 12 (3 hp) and 10 gauge (5 hp) . It’s quite easy to wire in the switch, you do not need to change the switch to motor wiring.
I have several 240 Volt machines in my shop which is in the garage, so they have to be moved around to allow the car to get in. The 240 volts comes in at one point and that's where the plug is. And you're right there's no such thing as a 240 Volt extension that you can buy at least I haven't found one. So, I made my own I got it a heavy cable I think it was like 10 or 12 gauge and stranded 3 wire and put two NEMA plug on one end and receptacle on the other. What you have to decide is which plug you're going to use because there are several types of plugs for 240 where there's only really one for 120. I had to change plugs on the several machines that I had because the one that came with it did not fit with the plugs I had chosen to use. I also had one machine that came without a plug just a pigtail so that was really convenient.
The reason you don't see 240 V extension cords is that there is no single plug/recepticle pattern that is universal. Currently there are 6 non-locking and 4 locking Nema approved plug patterns for use with 240V/20A apliances way too many to make it commercially viable to produce extension cords, although you do see some occasionally, usually associated with portable generators to connect with a transfer box.
I recently standardized using the nema L6-30 twist lock .
Like mdreed, I made one. I just needed about 6 feet so I could easily rotate the jointer/planer. I checked with a family electrician beforehand and got a thumbs-up that I was not going to burn the place down.
Mount a box and 220 outlet directly in machine and run the circuit to it. I use metal flex and just follow the ducts.
May not be “code” but there’s nothing wrong with it and it works.
You can see that in the distance on the planer.
May not be "code" could be the difference in your insurance company paying off after a fire.
"code" is really CODE, not an abstraction or hypothetical on any level.
I call BS.
Proof?
Really? Because it happens every day. Violate the building code and the insurance company has an easy out. And it's just not worth it. Sticking to code usually takes little if any extra expense or time.
This is such urban legend.
I challenge anyone to show me the line in their homeowners' insurance that states this exclusion for "not to code".
Granted every insurance company looks for every excuse but I believe the operative word you will find in your policy is NEGLIGENCE.
So, here's a quiz: Your shop is in the basement. You wire a 15A circuit using 12Ga Metal clad cable to a metal box.
a) You ground directly to the device (outlet).
b) You did not use a GFCI breaker.
c) You did not use a tamper proof outlet next to your bench.
Was this to code? If not why not?
Was it negligent?
oh, and yes, you did remember toinstall the anti-short bushing on both sides of the metal cable;)
Does it really matter what clause an insurance company denies a claim for? And yes I have encountered professionally situations where claims have been denied or greatly reduced because of improper electrical wiring, the number 1 reason is back feeding portable generators through a dryer circuit.
As to your other "test" it could be in violation of the NEC for 2 reasons, but local jurisdictions have the right to deviate in either direction from the NEC. If by metal jacket cable you mean modern MC that is not considered an acceptable ground conducter in the NEC, but that is why MC cable always contains a ground wire, you never specified what you connected as a ground. On the other hand if you are really referring to older style BX cable some local jurisdictions still permit that as a ground conductor but it's not recommended by the NEC. The only other code violation in your "test" is the lack of GFCI in a basement outlet required by NEC but again local jurisdiction are not bound by it if they so choose.
Did I pass the test?
Hmmmm for some reason I could not reply to your reply esch5995.
Yes, the lack of GFCI would be a violation of modern code.
Let lack of a tamper proof outlet would be another.
I should have specified the abbreviation MX to distinguish it from BX cable as MX has a dedicated ground.
Also the failure to ground both the device and the box would be another failure.
The points you make are exactly my points. There are many flavors of code. They depend upon where you live and the year in which the work was done.
An insurance company would be hard pressed to deny a claim for the above referenced circuit. Again, I challenge anyone to show a clause in their HO insurance that mentions building code of any sort.
Here is some of the stuff I found in a couple of properties I purchased... needless to say it was all replaced the better than code ;) Love the notched floor joists!!
My point is that the broad brush claim of "not to code" is indeed an urban legend. Negligence is the key concept here.
When I bought an 8" PM jointer that needed 220V I had the same problem. I solved it like several Above posters, I made my own. Wire is cheaper by the spool, so I went to big orange and bought a 25' spool of 10 gauge, cut it in half and made two 12' extension cords. Much preferred over trying to modify the machine itself.
I have a 25 foot extension cord for my 20 amp outlets.
https://www.amazon.com/NEMA-6-20-Extension-Power-Cord/dp/B00H54FZWW
I use a 10 footer I bought from Amazon without issues.
https://www.amazon.com/gp/product/B07K2TGLXZ/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&psc=1
Like mdreed, I made my own cord. My planner is mobile but I still like put it in the middle of the floor. So I just bought the ends and some cable and made my own.
I'm afraid I don't understand the infatuation with extension cords. If you are capable of making an extension cord you can simply put a longer cord on your tool, always a better option.
My first choice would be to run a new outlet closer to the tool. You can never have too many outlets. Second choice would be to wire a longer and heavier cord directly from the tool.
Extension cords should be a temporary solution. If it's going to be a long term thing, do it right.
No way to improve on @esch's answer but just to comment that with too long an extension cord, my jointer (also 3HP) would struggle to start. Beefy induction motor...
Even with a short cord, the lights would dim in the garage when it started up because the flex from the house to the garage was too thin for a workshop.
Code = minimum accepted standard. I agree, By the time you build an extension it would be cheaper an better to just add a longer plug. If you are doubling the length of 6' go from 14 AWG to a 10AWG just to be sure.
Note that Owners Manuals specify requirements/limitations for extension cords as well as machine cords in terms of wire gauge and length. I used a 220v extension cord "temporarily", and now finally have circuits/outlets run for tools in basement - not only is safer, but makes shop time much nicer all around and more productive. The garage tools are up next.
A bit astray from OP, but a tip about 220 plug configurations that maybe most already know, but I didn't: NEMA 6-20 receptacles accept both NEMA 6-15 and 6-20 plugs similar to the way a 110v 20amp outlet accepts 110v 15 amp plugs. I never realized this about 220v configs (although it is relatively obvious once you look closely at the 6-20 receptacle) until I got new dust collector with a 6-20. Before that, never had a reason or experience to know it and had wired 20 amp circuits with 6-15 receptacles because that is the only plug type I had at the time (e.g. tablesaw, bandsaw).
I had precisely the same issue with my 8 inch 3hp jointer. I bought
Parkworld NEMA 6-20 Extension Cord 6-20P to 6-20R (T Blade Female Also for 6-15R Adapter) 250V, 20A, 5000W (10FT) on amazon. My 220 outlets are
all NEMA 6-20R and the plug on this cord (and the jointer) is NEMA 6-20P.
Finally, the 220 circuit I installed meets code and has a 20AMP double pole
GFCI breaker on the subpanel.
An example of "what works" and "what's code."
A friend had a table saw running on a 120v, 20 amp circuit. He decided to rewire the motor to 240v, so he did that, and swapped the breaker from a single to double pole. It worked great. Electrically, it was just fine.
But he didn't change the plug on the saw's cord, or the outlet. They were still able to accept 15amp 120v devices. And eventually he needed an outlet, unplugged the saw, and plugged in an extension cord skilsaw. Turns out, you aren't supposed to run those on 240v.
If he had just run the table saw, his conversion worked just great. But it wasn't code. Code is there to make sure that bad crap doesn't happen, and people and property stay safe.
If you stop and think about it a PROPERLY SIZED extension cord is no different than running running that extra feet of romex in the wall. Electricity doesn't care if it is flexible of solid wire.
20 foot of properly sized extension cord is no different than 20 more feet in the wall.
The issue comes when someone doesn't use a proper sized wire or uses improper connections. It is not the extension cords that are the problems.
Without trying to drag this out into too technical a discussion, electricity does behave differently in stranded and solid wire. Because electricity actually travels on the surface of the wire, not through it, as commonly believed, stranded wire suffers from a higher degree of dissapation and is more prone to resistance increasing corrosion and severing, individual strains breaking thereby reducing the current carrying capability of a particular cable. This is why for a given gauge of wire stranded wires have a larger diameter.
Additional mechanical connections are also subject to corrosion and increased resistance which then increases the amperage load. Also unless they are the locking type they can also be prone to separation and potentially arcing and other serious problems. And God forbid your shop is like mine and it tends to turn into a swimming pool every 5 years or so and you have all those unsealed electrical connections lying on the floor.
Now I know these situations are not common or take years to develop and many of you will say you've used extension cords without problems. But why take the chance when...
There is a much simpler reason to avoid long term use of an extension cord. To make an extension cord you must buy both a plug and receptacle in addition to the cord. These aren't cheap sometimes. If you simply replaced the cord at the machine you only need the plug portion of the connection. If your tool comes with only a pigtail installed and no plug then you save buying 2 connectors.
There is a reason tool manufacturers and appliance manufacturers warn against long term use of extension cords.
Extensions are not about wire size, it’s easy to decide on the right gauge wire . It’s about having two more connectors, not in a junction box likely laying on the floor .
Connectors are far from being equal. Many inexpensive connectors are undersized, plated, or have other issues. I recently returned a 12 gauge extension cord as soon as I opened it. The wires seemed properly sized, but the connectors looked like they would run a lamp.
Here's what I did as I bought an older 8" jointer needing a new motor.
I bought 12' of SJOOW wire (Service Junior-300V, Oil resistant inside insulation and outside jacket, Weather Water resistance). You could also buy SOOW. It is rated 600V and is thicker than the Junior version. They are both available in 12 gauge which is likely all you'll need. As mentioned before, you only need to replace the wire from the switch to the plug. Since I installed an entire circuit I installed a two pole, 20 AMP breaker. The wire from breaker to outlet is 12 gauge and I bought solid THHN wire and ran it through 1/2" conduit. The outlet and receptacle I used were Leviton 5821-W and a Leviton 5466-C respectively. Other styles and brands may be suitable.
I had an amazing photo of a bus bar that was red hot due to poor design, but never located it, but I did find this !
A guide to fuse replacements
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