Good Electrician?

[Floyd Hall]

I'm looking for a good electrician in the Mount Airy-Pilot Mountain-King area. I'm in talks to buy a radial arm saw and I need to know if I have enough space on the box and/or what is involved with a 3-phase tool.

TIA,

Floyd

 

[bowman]

3-phase power is typically used in industrial/commercial locations. I do not know if your electricity supplier will bring 3-phase to your residence/workshop unless they can make a profit from it.

If you are intent on getting a 3-phase tool, you will need a device to convert single-phase 220 to the three phase feed for the tool. Several members ob here are using that setup.

Contact Harry's Electric in King.

 

[Floyd Hall]

3-phase power is typically used in industrial/commercial locations. I do not know if your electricity supplier will bring 3-phase to your residence/workshop unless they can make a profit from it.

If you are intent on getting a 3-phase tool, you will need a device to convert single-phase 220 to the three phase feed for the tool. Several members ob here are using that setup.

Contact Harry's Electric in King.

Thanks. I've been looking at a 1-phase and a 3-phase RAS, both 16i and 5 hp, but the 3-phase seems to be in much better condition. I'm trying to decide which will work better given what I've got service-wise and how much trouble/expense it would be to go for the 3-phase. I think what I would need for 3-phase would be a rotary phase converter. But need to know what that would involve.

Anyway, I'll give Harry's a call. Been waiting for more than a week for my electrician to get back to me and I'm tired of waiting.

Floyd

 

[redknife]

Randy at Bretco electric. They rigged up my 3 phase 15 hp rotary converter and plenty other work. FYI, I asked Duke if they could run 3 phase to my house. A nice guy came and throughly evaluated the situation. Three phase to my house would have involved upgrading the lines from the main road through a bunch of neighboring properties. Pole location changes, etc. Said it would be expensive and time consuming to get neighbors to agree. So I went rotary phase converter.

 

[Floyd Hall]

Randy at Bretco electric. They rigged up my 3 phase 15 hp rotary converter and plenty other work. FYI, I asked Duke if they could run 3 phase to my house. A nice guy came and throughly evaluated the situation. Three phase to my house would have involved upgrading the lines from the main road through a bunch of neighboring properties. Pole location changes, etc. Said it would be expensive and time consuming to get neighbors to agree. So I went rotary phase converter.

Think I tried Bretco once before, but they didn't want to come up this far. I'll try them again. Thanks.

Floyd

 

[ehpoole]

I'm looking for a good electrician in the Mount Airy-Pilot Mountain-King area. I'm in talks to buy a radial arm saw and I need to know if I have enough space on the box and/or what is involved with a 3-phase tool.

TIA,

Floyd

As far as space in the box, you will only be using two adjoining positions/slots since your present panel is single phase power and you are seeking to run a 3-phase converter (either rotary or solid state) which will be a typical 240V circuit that powers your phase converter. The real question will be whether or not you have sufficient (amperage) capacity available in your panel (including any upstream panels that may be feeding the shop panel) as a 5HP motor is a rather large motor (especially on startup and under heavy loads) and the 3-phase converter will incur additional losses above and beyond those of the 5HP motor, so you need a bit more power still to accommodate the 3-phase converter. You may wish to consider going the route of a 3-phase VFD (variable frequency drive) as your 3-phase converter so that the VFD can be programmed to more slowly ramp up (soft-start) the motor so that your peak startup load is considerably lower than trying to instantly bring the motor up to speed, especially if your panel does not have the 50+ amps to spare. The good news is that once the motor is up to speed it will draw much less power than at startup unless you get too aggressive and start heavily loading it.

That all said, though, my own personal feelings (so take such as one may) on 3-phase equipment in a single-phase shop is that it generally is not desirable unless you are planning to acquire further 3-phase equipment and because a lot of 3-phase equipment tends to have much larger motors than our typical single-phase shop equipment you tend to require more capacity in your panel to accommodate the larger motors and their peak startup demands (plus the power requirements of the converter). However, most of the industrial 3-phase equipment tends to be of better construction and quality than our consumer gear and used 3-phase motors (and the equipment, if within the consumer realm) tend to go relatively cheap precisely because using them in a typical small single-phase shop requires jumping through added hoops and further investment in equipment and electrical to generate the required 3-phase power, so they do have those pros going in their favor on average. If you only have a single 3-phase tool and do not plan to acquire more then consider using a solid state converter or VFD as you can save money and a VFD can be programmed to soft-start the motor to reduce the peak amp draw on startup. On the other hand, if you plan to outfit your shop with multiple 3-phase tools then it is often more economical overall to go ahead and invest in one large rotary phase converter, provided your panel has sufficient capacity to accommodate the much larger load, and install a small 3-phase subpanel and then distribute 3-phase receptacles radiating out from that subpanel, that way you are not having to buy multiple converters (one per tool) in the future. Only you know what your future intentions and needs may entail, so weigh such options as you feel appropriate.

Rotary phase converters do add an additional step to powering on and off your 3-phase equipment since you must first start the rotary phase converter and bring it up to speed, and then power on your equipment as needed, then shutdown the rotary phase converter when finished, so they are not ideal if you only use the tool opportunistically for just a few minutes at a time or to make a quick cut -- typically the rotary phase converter is started when you begin the day and not shutoff until you are done for the day (or afternoon, whatever your typical "work shift" is) but it will consume some wasted power in the interim while it's running in the background. By comparison solid state converters/VFDs can be started and stopped on demand and are more compatible with opportunistic short use periods and can be powered on and off with the equipment, so there is no added step (save possibly waiting an extra few seconds for the soft-start to bring the motor up to speed before you begin). So your typical usage pattern may encourage you to choose one converter option over another...we all use our tools differently, some of us wait until we have a large batch job that can be done all at once while others will make a few cuts then shutdown and may or may not return for more cuts sometime later resulting in short average runtimes (being disabled and slow as molasses I often tend towards smaller and shorter runtimes for most tools, with occasional extended run periods, so I'm in the more "opportunistic" usage camp).

Whatever you end up deciding, I wish you all the best! If you should go the 3-phase option, I would really encourage you to consider taking some photos and documenting the process so that you can share your experience with others whom may also be interested in 3-phase equipment and the necessary 3-phase power conversion process for their single-phase shops as this topic comes up every now and again and often garners some real interest.

 

[Floyd Hall]

That all said, though, my own personal feelings (so take such as one may) on 3-phase equipment in a single-phase shop is that it generally is not desirable unless you are planning to acquire further 3-phase equipment and because a lot of 3-phase equipment tends to have much larger motors than our typical single-phase shop equipment you tend to require more capacity in your panel to accommodate the larger motors and their peak startup demands (plus the power requirements of the converter). However, most of the industrial 3-phase equipment tends to be of better construction and quality than our consumer gear and used 3-phase motors (and the equipment, if within the consumer realm) tend to go relatively cheap precisely because using them in a typical small single-phase shop requires jumping through added hoops and further investment in equipment and electrical to generate the required 3-phase power, so they do have those pros going in their favor on average. If you only have a single 3-phase tool and do not plan to acquire more then consider using a solid state converter or VFD as you can save money and a VFD can be programmed to soft-start the motor to reduce the peak amp draw on startup. On the other hand, if you plan to outfit your shop with multiple 3-phase tools then it is often more economical overall to go ahead and invest in one large rotary phase converter, provided your panel has sufficient capacity to accommodate the much larger load, and install a small 3-phase subpanel and then distribute 3-phase receptacles radiating out from that subpanel, that way you are not having to buy multiple converters (one per tool) in the future. Only you know what your future intentions and needs may entail, so weigh such options as you feel appropriate.

Thanks. I've been looking into this for several weeks now and that is probably the most thorough answer I have gotten back. I just decided to look into radial arm saws because I looked at the shape of my shop -- about 12ft x 30ft -- and decided a RAS would serve me better for cross-cuts and dados than a full scale table saw with a 52i fence. The problem is finding the right one, which has been difficult. Most the saws I've seen only have a cross-cut of 12i or so, which is not quite enough -- I can get that with a sliding compound mitre saw. So I've been looking at bigger 16i radial arm saws, which have a 20i cross-cut. There are two of them out there right now, both 5 hp. One is 1-phase and the other is 3-phase. The 3-phase seems to be in better shape. The question is whether it is practical. From what you are saying it's probably not. I'm working out of my basement right now. I do have an outbuilding I can move into at some point and set up for 3-phase, but that's a good ways down the road. Meanwhile, I need to talk to an electrician to see if I can even comfortably run the 1-phase.

Thanks a lot.

Floyd

 

[Floyd Hall]

3-phase power is typically used in industrial/commercial locations. I do not know if your electricity supplier will bring 3-phase to your residence/workshop unless they can make a profit from it.

If you are intent on getting a 3-phase tool, you will need a device to convert single-phase 220 to the three phase feed for the tool. Several members ob here are using that setup.

Contact Harry's Electric in King.

Thanks. He's coming right out this afternoon. Appreciate it.

Floyd

 

[redknife]

Pics of prior 3 phase install (moved):
https://www.americanrotary.com
Here is the inside of the phase converter, one focused on the connections, and another the broad view of the box. The ins and outs are: single phase from panel, lines to motor on floor, 3 phase line outs. Single phase connects bottom left. Motor and 3 phase connect mid right.

That gray cable coming forward goes to the case on/off switch.
Here is the sub panel that receives the 3 phase from the phase converter and then has out for shaper and power feeder in my case.

 

[Floyd Hall]

Thanks!