Electrical outlets

[CueWood]

This maybe a big newbie mistake I'm not sure, but I have my lathe plugged into a surge protector. I didn't do any research I just plugged my lathe in an started turning. My lights dim when I first turn it on.
1. I wanted to know what is the best way to plug my lathe or any lathe in?
2. Do I just plug it in an outlet by itself?
3. Does the outlet need to be GFCI?

**I use the harbor freight lathe now (the large central machinery one) but I plan to upgrade to either the Jet 1221 or the Laguna 1216**

I'll appreciate any help and suggestions.

 

[jttheclockman]

This maybe a big newbie mistake I'm not sure, but I have my lathe plugged into a surge protector. I didn't do any research I just plugged my lathe in an started turning. My lights dim when I first turn it on.
1. I wanted to know what is the best way to plug my lathe or any lathe in?
2. Do I just plug it in an outlet by itself?
3. Does the outlet need to be GFCI?

**I use the harbor freight lathe now (the large central machinery one) but I plan to upgrade to either the Jet 1221 or the Laguna 1216**

I'll appreciate any help and suggestions.

No GFI. DC motor and speed control will effect circuit.

 

[egnald]

Some motor controllers, especially those that use Variable Frequency Drives (VFD) can be very problematic when it comes to false GFCI tripping. I don't think the HF uses VFD so it probably shouldn't matter.

As for dimming lights when you first turn it on (I'm assuming they are dim for just a brief second and don't stay dim). This can be caused by a heavy initial draw, often associated with a surge of current when certain devices with higher inductive loads are initially powered on (a table saw for example). It is not uncommon for inductive loads to draw a considerable amount of AC current when they are initially switched on which causes a small voltage drop in the intervening wiring (due to I2R losses). This usually shows up by incandescent lights dimming briefly or even some LED lights as the newer "dimmable" offerings can be sensitive to this kind of stuff.

The best ways to combat this are to use a less loaded circuit and/or increase the size of the conductor and/or reduce the length of the conductor. So, if you are using an extension cord try plugging your lathe in directly to an outlet to see if it makes a difference. If your lights stay dimmed when it is turned on then you probably have a different kind of electrical problem all together.

My recommendation would be to plug it in to the outlet with as short of an extension cord as you can, no surge protector, no GFCI and see if it makes a difference.

Regards,
Dave

 

[derekdd]

I agree with Dave's take.

I looked online but couldn't find how many amps it wants from an outlet. It's a 3/4 hp motor, some I'm guessing 15 amps. Some of my 120v power tools want 20 amp outlets and will trip breakers if I work them hard on a 15 amp outlet.

Our garage had just enough power to run two garage door openers and a light. I had to bring in a subpanel with 80 amp service to run all our tools.

 

[bsshog40]

When I had my shop in W.Tx., everytime I turned on my big tablesaw, my lights would dim for a second. I'm pretty sure whoever wired it ran 12ga for all of the outlets, 15 and 20amp. When I ran my wire in my new shop, I used 10ga on all my outlets. No more dim lights when I turn on my tablesaw now. It's a 3hp 15amp saw. Moral of my story is making sure the wiring on your outlets can handle amperage.

 

[jttheclockman]

Well there is alot more to diming lights but loading a circuit does count. If you are running an extension chord what size wire, what size wire to wire the outlet you are plugged into, how much other devices on that circuit and are they running at the same time. lights should not be on the same circuit as outlet so there should be no dimming for a simple lathe with no load on it. Even if they are on the same phase, what kind of lights are you using. Anything electronic can play havoc with other things. Now 2 things were mentioned surge suppressor and GFCI Now they make hospital grade GFCI which are far superior to what is sold to homeowners. they also make GFCI units for Tools that have VFD drives but again these are very expensive and just not needed unless you are working in a wet area. Why would you be working in a wet area with power tools? Garage shops and outdoor sheds are tricky because of those codes.

 

[jrista]

Well there is alot more to diming lights but loading a circuit does count. If you are running an extension chord what size wire, what size wire to wire the outlet you are plugged into, how much other devices on that circuit and are they running at the same time. lights should not be on the same circuit as outlet so there should be no dimming for a simple lathe with no load on it. Even if they are on the same phase, what kind of lights are you using. Anything electronic can play havoc with other things. Now 2 things were mentioned surge suppressor and GFCI Now they make hospital grade GFCI which are far superior to what is sold to homeowners. they also make GFCI units for Tools that have VFD drives but again these are very expensive and just not needed unless you are working in a wet area. Why would you be working in a wet area with power tools? Garage shops and outdoor sheds are tricky because of those codes.

Aye, if you have any kind of advanced motor drive, you probably don't want to be using a GFCI circuit breaker. I upgraded to a Powermatic 3520C last year, and added a new 250V outlet for it. I tried to use a pretty good GFCI/ACFI breaker that was fairly advanced with it, but this lathe has a VFD and NOPE. Thing runs like a charm with a normal (and SIGNIFICANTLY cheaper) 250V breaker.

What I did was install a 270V rated switch so I could turn the outlet on and off. When I'm not using the lathe, its disconnected from the power entirely. I feel safer this way.

 

[monophoto]

Some motor controllers, especially those that use Variable Frequency Drives (VFD) can be very problematic when it comes to false GFCI tripping. I don't think the HF uses VFD so it probably shouldn't matter.

As for dimming lights when you first turn it on (I'm assuming they are dim for just a brief second and don't stay dim). This can be caused by a heavy initial draw, often associated with a surge of current when certain devices with higher inductive loads are initially powered on (a table saw for example). It is not uncommon for inductive loads to draw a considerable amount of AC current when they are initially switched on which causes a small voltage drop in the intervening wiring (due to I2R losses). This usually shows up by incandescent lights dimming briefly or even some LED lights as the newer "dimmable" offerings can be sensitive to this kind of stuff.

The best ways to combat this are to use a less loaded circuit and/or increase the size of the conductor and/or reduce the length of the conductor. So, if you are using an extension cord try plugging your lathe in directly to an outlet to see if it makes a difference. If your lights stay dimmed when it is turned on then you probably have a different kind of electrical problem all together.

My recommendation would be to plug it in to the outlet with as short of an extension cord as you can, no surge protector, no GFCI and see if it makes a difference.

Regards,
Dave

Agree with everything Dave said, but would add one further thought.

The absolute best arrangement would be to have separate circuits for lights and machines. It's unlikely that you would be using more than one machine at a time (unless you have a 'helper' in the shop), so one receptacle circuit for power tools should be sufficient. But having one (or even better, two) separate lighting circuits means that if something should happen (and stuff does happen in the shop) that causes a circuit to trip, you won't lose all of the lights. It would be very dangerous to be using a machine such as a lathe, table saw or band saw, and have the lights go out while the machine continues to run.

Many of us have our shop in the basement. The National Electrical Code requires that basement receptacles have GFIs. I think you could argue that a dedicated circuit for semi-permanently plugged-in shop machines could be exempted from that rule provided the remainder of the receptacles in the area (those where tools are plugged in only when used) have GFI. I have a slop-sink in my shop, so I made a point of putting a GFI on the receptacle circuit. But the lights in the shop are on a separate, general purpose basement lighting circuit so that they are independent of what happens with tools.

 

[Woodchipper]

GFCI not needed for the lathe. I have done considerable residential wiring. 12 ga. was the standard for the home. We used 12 ga. all through the house even though 14 ga. was OK overhead lighting. Never could understand using two types of wire. Need to check my box; only lines on GFCI are the kitchen, bathrooms and outdoor lighting. I had to add a line for my shop for the lathe, TS, etc.

 

[bugradx2]

I'm going to agree with the others, if you have the ability to plug directly into the wall then I would do so. Certainly skip the surge protector. I have a purpose built shop in our basement (benefit of new construction subdivision) that has 15 amp circuits for the lights/ceiling and 20 amp for the wall outlets. Because it's a basement, code requires a GFI on each circuit for the wall outlets, not required for the ceiling. I have the wall circuits split to two different breakers too