Unisaw Switch Update

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Re: 4 HP motor install
Spoke to the local motor experts. The standard Unisaw switch is sufficient. He did have and offered to us a switch with the built-in LVC unit, for $254. He said we need a 35 amp breaker and #8 wire. He also said a 5HP motor would require a different switch and larger breaker, also.
Local electrical supply, next door to the motor specialists co., had all supplies we needed. There is no 35 amp breaker, so a 40 amp will do. While there, we spoke to an electricain and he'll do the wiring this afternoon. Electrician recommended a (clothes) dryer cord and outlet box, rather than the cord and outlet Jonas has.
Did any of you have any questions or concerns, that is not covered above? I'm sure I can get more info from the electrician and motor guys.
Sonny
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Okay, another update. Electrician came out and discovered the switch was wired wrong.
Everything we initially had was appropriately sized for the saw, motor, etc. The 12-2 wire was sufficient, the 20 amp breaker was sufficient and the 220 outlet was sufficient.
The saw runs fine. The amp draw is 6 amps at continuous run (according to the electrician and his meter). He said the start-up didn't approach the capacity of the breaker, the switch or any other aspect of the electrical system. He wired it correctly and said we were good to go.
The supplies Jonas bought, mentioned earlier, can be returned, since they were beyond what was needed. We may be able to return the #8 wire, also, or at least possibly get a partial refund, since it was cut from a roll.
Sonny
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On 5/21/2012 1:53 PM, Sonny wrote:

Nothing like "boots on the ground" ... even the motor expert and electrician didn't agree until someone got some hands-on on the ground.
You sure that motor is not 3 HP? ;)
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On 5/21/2012 4:17 PM, Swingman wrote:

Did the electrician measure that amp draw under load? If you're ripping a piece of 2" thick maple you might find that the current draw is much higher. I find it hard to believe that a *5* HP motor only draws 6 amps. I have a 3 HP that draws more than that. On 220V. It's not a Craftsman motor is it? (just kidding)
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Max wrote:

If it was "cut from a roll", it would surprise me if it was eligible for return, rather like a cut from a roll of carpet. I guess it just depends how saleable it is and where you bought it, etc. etc.

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Somebody wrote:

------------------------------- The sign behind the counter usually reads, "No returns on cut wire", or something similar.
At least in all the years I was associated with electrical distributors it did.
Lew
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-------------------------------

Yeah, I'm familiar with that policy. We thought there may be a chance of getting some refund, as per the electrician's phone call. Jonas didn't get any refund, after all. Oh well, a $50 lesson learned.... not a bad cost.
Sonny
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On 5/22/2012 10:06 PM, Max wrote:

Your point goes right back to my contention that because something works doesn't mean that it is the optimum solution.
Makes you wonder how the "motor experts" at Judice feel, based on their knowledge of motors, about being so far off base with the electrical design requirements from what the electrician determined on site?
And Lew's assessment, based on many years in the business, was certainly in line with the "motor experts". In over ten years of watching his participation here, I've not seen one single instance of his electrical advice when it comes to electrical design requirements being nothing but absolute spot on.
I gotta admit to a raised eyebrow about the final solution since I've known so many numb nut electricians in the construction business, but the proof will be in the pudding and it could be be just fine for the intended use, which is all that matters in any event.
I will say unequivocally about the final solution for a cabinet saw, providing it is indeed a 4HP motor: "not in my shop".
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Well, the electrician may still be a little off, if a load on the saw requires increasing the wiring and breaker size. His assessment, of amp draw and overall sufficiency of the system, was based on the non- loaded running of the saw.
Sonny
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On 5/24/2012 6:18 AM, Sonny wrote:

According to manufacturing spec, my 3HP Unisaw should run fine on 220/20A with 12g wire, and apparently most of them do.
I ran it without issue on a 20A/10ga dedicated circuit for years until I moved it to another shop location for a couple of years and initially tried to run it (using the exact same c'bkr I brought with me) on a 20A/12ga dedicated circtuit (with about +/-5' more distance to the sub-panel).
In the new location the saw would periodically trip the circuit breaker (and occasionally the thermal overload button on the motor would pop, which had never happened before).
I rewired that approximately 5' longer home run with 10ga wire and never had another problem in that shop. Length of home run in both cases was between 20 - 25' max.
Lots of variables to take into consideration here, but one would think that a small increase in distance, that was under 50' to start with, coupled with a smaller wire size, wouldn't make that much of a difference, but it obviously did with this particular saw.
IOW, and for whatever reason, not flirting too close to the maximum circuit capacity with equipment like a table saw can often save some needless frustration.
YMMV ...
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The charge was $85 for the electrician's work. It took less than an hour and two guys showed up, whereas only one guy was spoken to and hired at the supply house. I suppose they worked as a team and the other guy wasn't in the supply house when we spoke.
A reasonable job was performed and this cost was well worth the peace of mind, also.
Sonny
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That's a reasonable price. I don't know what part of the country. But here in NJ that would just cover a visit, with no work.
On 5/26/2012 10:52 AM, Sonny wrote:

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On 5/24/2012 6:49 AM, Swingman wrote:

And that has been my experience as well.
Max
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No. A blade can't be installed at the moment because the flange, to help hold the blade in position, is missing. If the breaker trips when a load is applied, we can easily up the wire and breaker size.

The motor is 4 hp and the spec sheet does indicate it is for a saw.
Sonny
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wrote:

I hope he taught you and Jonas how to read a VOM so you can avoid that next time.

That nameplate amperage for the other motor was 17.something, so I figured it might be OK as-is.

What'd he nail you for, chargewise?

Good luck with that.
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The methodology/approach that must be taken into account when answering questions of this nature, sight unseen, is not whether something "works", but whether it will pass an inspection and be in compliance with "minimum standards" as set forth in models like the NEC. To do otherwise is a disservice to the integrity of the advice proffered in a forum of this nature. This fact was clearly illustrated by many of the answers here, as well as the answer provided by the "motor expert".
Let's not fall into the trap of assuming that because something "works", that it is an all encompassing solution that automatically makes others "wrong".
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Which reminds me of some wiring I found in the basement of my house when I bought it... About 40 feet of old lamp cords were taped together to run a wire across the basement, laying on the hung ceiling, and out through the exterior rim joist and siding to power a dual bulb outdoor flood light. Yes the lights worked but the wire gauge was probably something like 20 or 24, there were a bunch of open air connections, no work box at the fixture, and no ground.... The wire was also really warm while the lights were on. Needless to say, though it worked I ripped it out immediately.... ;~)
John
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On 5/22/2012 7:43 AM, John Grossbohlin wrote:

I mentioned it here in past about coming close to a catastrophe some 23 years ago when my then 4 year old came into the garage one afternoon to tell me about the "pretty lights" in the living room.
The "pretty lights" was a fire in a wall that started because someone 30 years earlier had added a receptacle on the opposite side of the same wall and simply twisted the wires together inside the wall with electricians tape.
It worked, and lasted 30 years ... just thank gawd it was 1:30 in the afternoon, instead of the morning, that it finally failed. Our bedroom was on the opposite end of the house from that wall, which was one room away from our daughter's bedroom.
I decided at that time that in the future I would inspect all electrical work myself, not take anything for granted, and that any work of that nature I did personally would be on a fully informed basis and be in compliance with applicable codes ... no exceptions.
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Jonas was prepared to pay them, but the electrician said their office would bill him. For a quick job as this, I was surprised payment couldn't have been settled then. I'm interested in what may be charged, also.... about an hour's time.
The electricain who ran the underground wire and wired my shop subpanel charged me $45. The 6" underground PVC pipe was already laid for the wire run, so the electrician didn't have to do any digging or such, etc. and I had all the supplies he needed.

When at the electrical supply, we met the electrician who was eager to help, so was hired at that time. According to our info, specs, etc, he told us what was needed, as the salesman wrote down his recommendations. Later, at Jonas' shop, the electrician phoned the supply co. and explained we didn't need most of the items, after all. Jonas is to speak with Darrell, one of the supply suprevisors, about the wire refund. Jonas bought 40' of wire, so for that guage, maybe 40' is readily reuseable and he may get whole or partial refund. Otherwise, Jonas has no use for that size wire. I guess it depends on the circumstances, for some refunding, as this, and, it seems, the electrical suppy is willing to try to accommodate its customers, when possible. *Sounds like good customer service, to me! Seems the electrician and the Supply Co have a good working relationship, also, since it only took a phone call to make the arrangements for the possible refund.
Sonny
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Absolutely true...if he were doing wiring, but this was a switch on a table saw, with (I assume) a pigtail going to an existing outlet. How often are those inspected? I'd probably have replaced those breakers, too, but he hired the electrician most of us suggested.

My train of thought was "It should work safely", I found out that it did, and then I thought "Good." No neeners or exclusionary thoughts entered my mind here, nor did any show up in my post, so why did they there, Swingy? Puzzling.
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