Shopsmith Forums

Going against the flow is something I understand. When doing so, one must be aware of the risks inherent in that.

In this case the appliance(the M7) has a fixed power cord with a plug attached. As it arrives from the mother ship, it has a 120v 15A plug.

Now it is designed to also run on 240v, but that plug is inappropriate when doing so. Why? As Dennis already explained to wire a 115v receptacle to 240v runs the later risk of the scenario he described.

So just make a pigtail(cheater cord). Properly wire a 240v receptacle(that eliminates the scenario above)(until an unsuspecting person discovers the cheater cord and duplicates the same result.

Better(far from perfect) option is to replace the 120v plug on the M7 with a 240v plug. These are the same size as the 120v, but the blades are oriented differently. That difference is to prevent the previous scenario again.

Now the m7 will plug into a 240v receptacle and NFPA is happy.

But, you also desire to run it on 120v(perhaps as a need because of transporting it where 240v receptacles are not available).

Again a cheater cord could be made, but this time the risk is less(still significant). Plugging a 240v appliance into the 240v cheater receptacle as the 120v plug end is plugged into 120v may or may not cause a hazard depending upon the appliance itself. It is the lesser of the evils, but is still a risk. I know, the repetition was intentional.

Now unless the transporting is likely, IIWM, I would just use 240v connectors.

As for your electrician he should not do anything contrary to the NEC. I suggest he wire a 15A branch circuit at 240v with a 240v 15A receptacle.

If doing an 'over head drop', a twistlock receptacle is prudent.

I realize the $10 already spent is tugging, but I do not think the mating receptacle(125v 30A) is less than the cost of a 240v 15A receptacle + that $10. No I have not 'priced' them.

I would go against the flow myself, but cannot recommend the same for others in this case.

rjent wrote:It is, after all, your machine and your building. Your M7 can be plugged into 110 or 240 as you see fit ..... great solution!

Dick

Yes, I often swim against the flow ....

So if the house burns down, the Insurance company won't disallow the claim?

beeg wrote:So if the house burns down, the Insurance company won't disallow the claim?

Therein lies the 'risk' referred to!

Used with the M7, a cheater should not lead to a fire. However if they be looking for an excuse. . .

If any of you PowerPro owners ever want to make up a dual-voltage power-cord adapter that meets code, here's a way to do it.

First, remove the 110V plug from the PP cord, and replace it with a "unique" male power connector that will not plug into any standard 110 or 220V outlet. More on that in a minute.

Second, make up two adapter cables, one for 110V and the other for 220V. Install a standard male power plug on one end of each, and a mating "unique" female connector on the other end.

Now, using the appropriate adapter cable, you can plug your PowerPro into either a 110V or a 220V outlet. But because of the unique connector, there is no chance of plugging a standard device into the wrong voltage.

Here's a link to some suitable "unique" connectors for a 15A circuit. They are rated 400V, 16A, are UL listed, and have a make-first protective-ground pin. To make sure that you will get a good grip on the power cord, choose the ones that match the diameter of your cord. Connections are made using screw terminals inside the connector backshell. Total cost for one male and two female connectors is about $50.

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Wow, that seems like a really good idea.

BuckeyeDennis wrote:If any of you PowerPro owners ever want to make up a dual-voltage power-cord adapter that meets code, here's a way to do it.

First, remove the 110V plug from the PP cord, and replace it with a "unique" male power connector that will not plug into any standard 110 or 220V outlet. More on that in a minute.

Second, make up two adapter cables, one for 110V and the other for 220V. Install a standard male power plug on one end of each, and a mating "unique" female connector on the other end.

Now, using the appropriate adapter cable, you can plug your PowerPro into either a 110V or a 220V outlet. But because of the unique connector, there is no chance of plugging a standard device into the wrong voltage.

Here's a link to some suitable "unique" connectors for a 15A circuit. They are rated 400V, 16A, are UL listed, and have a make-first protective-ground pin. To make sure that you will get a good grip on the power cord, choose the ones that match the diameter of your cord. Connections are made using screw terminals inside the connector backshell. Total cost for one male and two female connectors is about $50.

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algale wrote:Wow, that seems like a really good idea.

Fer sure!!!! I knew not where to look for a suitable connector.

There is that Miller welder connector but it does not fit the application. This does!!!!!

Good Job Dennis!!!!!!!!!!!!

When we had this discussion before. I could only find connectors that were designed for hook up to a ballast system and was pointed out not acceptable for 240 purposes.
After looking at the specs I believe you have found the best solution to date!

Frankly the chance (not even plural) of anyone misusing any pigtail is less than nothing. This place will have new owners after I die and I have no visitors to the shop. But just to satisfy yet another bureaucrat that (for the sake of a paycheck) believes he/she has to save me from myself , I will comply. I wonder if GR was thinking of our congress and oval office when he created the Borg? That and so that no one on this forum has to worry about a possible electrical fire (though I think they should be MORE worried about the big tanks of OX and ACY in the garage! Yes, chained and even capped when not in immediate use!

I sent emails to both SS and Tekna regarding the Miller welder cord but received not a single reply.

As JPG said, I plan on taking the M7 on a road trip and doubt that the landlords would think highly of me adding a circuit to their garage. Since I negotiated a short term lease I don't want to spook them by asking!

Yes, you are all absolutely correct regarding my electrician. He would not install anything which wasn't 100% code. And for as little as I pay him, he would wonder where the bribe money came from and go back to charging me more!

Life is still in a holding pattern, but I may receive clearance to land in a couple weeks!:D . It's amazing how therapeutic making saw dust of my own choosing can be and how much I miss it (and get cranky!!) when denied the opportunity!

Be well
Ben

PS as a related but slightly change in content (can I hijack my own thread?? ), I will be attending an electronics show in January with the idea of approaching a vendor to make power cords similar to the Miller welding units but three wire and prong. I kind of figure if Tekna and SS aren't interested, I might see what a test run of a hundred might cost. More info and update in February.

Dennis,

Thank you, I have been looking for something like this.

Jack

Jack Wilson wrote:Dennis,

Thank you, I have been looking for something like this.

Jack

Glad I could help, guys. I discovered Binder connectors while searching for a solution to a similar design challenge at work. There are lots of military and industrial connectors that could be used, but most are quite pricy. Excluding "standard" AC power connectors, these particular Binder connectors are the most cost-effective that I've seen in this power range.