Electricity Fundamentals Question - Long

[Eric Shields]

I am currently attempting to plan the lighting and electrical layout for my basement workshop. I am an electricity novice (read illiterate) and am seeking advise/education on the subject.

What I am trying to gain from your input:
Creat the most flexible, yet simple electrical layout/plan

After I complete the current framing phase, I plan to disconnect and reroute the current electrical layout (ie remove the existing lights and wiring within the basement then reconnect any wires that were shared with the basement fixtures back to their appropriate feeds). I will then place the new outlet boxes and run wires back to where the new sub panel (type and size undecided - not enough information yet) will be installed. I will have an electrician install the sub panel, install fuses, and do the final connections to the runs I have installed. Hopefully he will further educate me along the way, though I do plan on discussing the layout prior to running any wire.

The shop is/will be a one man operation (most of the time). However, I do see the possability of working together with my Father, FIL, BIL, and hopefully one day, my step son.

At the moment I do not own the stationary equipment that will eventually fill my woodshop (plan on basics, TS, BS, CMS, Cyclone, Planer, Joiner, etc). I am still using my "portable" tools I purchased when we lived in a townhouse. I will be replacing these tools as needed/funds available once the renovation is complete. So, not knowing the exact specifications of tools and wanting the most flexible arrangement for the future, what would you do?

What I do know/would like to do:
Install sub panel (lockable off) for safety and flexability
Multiple circuits for lighting - not all on sub panel
Multiple circuits for electrical outlets (120)
Multiple circuits for electrical outlets (240)
Separate circuit for DC (cyclone), Compressor (if needed), etc
Large tools shoud be limited on the same circuit
Single Phase Tools (for the foreseeable future)

Lighting Plan
8 x 8' (4 x 4' T8 Light Bulbs) - plug in
8 x 4' (2 x 4' T8 Light Bulbs) - plug in
Mount one duplex outlet at ceiling height per fixture leaving one socket for secondary or task lighting as needed

Electrical - Initial Thoughts:
Placed approximately 6' apart
Alternating a quad 120 outlet and a duplex 120 w/ 240 outlet
Placed approximately 50" from the floor to the bottom of outlet

Basic Questions:
How many lights can be on a single circuit
Can the same set of lights be controlled by three seporate wall switches, I know you can do two switches
How many outlets (120 or 240) can be on one circuit

Things that really confuse me (definite education needed)
What guage wire is used for 120, 240 for a woodshop
Wire run in conduit or Romex, why
Is there a standard amp for 120
Is there a standard amp for 240
Can I install all 240 lines and run machines at 220, 230
Can something that runs on 20 or 25 amps run off a lie that is 30 amp
If I run all 240, can I just change the fuses to the needed amp

Thank you all once again (electrically inclined especially) for your help and advise. One day I will be on that side of the creek, wading information across to those who need advise.

Eric

[Jim Becker]

Eric, if you have enough electric for your lighting available with the current circuits in the space, you may want to consider re-using those circuits for your new lighting. (I'm talking both existing lighting and existing outlet circuits). In that way, your sub-panel could be equipped with a disconnect, allowing you to shut off all your machine circuits in one swipe...a nice safety feature!

120v and 240 v are the standard voltages coming off your service in almost all areas. the terms 110/115/120 and 220/230/240 are used interchangably. Amperage for a circuit is a combination of what the needs are as well as the ratings of the wire and other components.

IMHO from reading your questions, you need to get some help from someone familiar with "the rules". Even if you want to do the rough work, have a licensed electrician help you with the design and have them complete the hookups. This is not something to fool around with if you are not crystal clear on the requirements.

[Spence DePauw]

Eirc, I'll just add a few comments based on what I did.

First, I have a couple of 110 circuits for utility outlets. All other 'outlets for tools' are one outlet, one breaker, whether 110 or 220. Also, I ran all of those 'tool outlets' with 10 ga wire. That way, when I get new toys, I can change the outlet and the breaker, without getting into the walls, and any outlet can become up to a 30A 240 outlet. ( I've done that 3 or 4 times in four years ) Lots of flexibility. The price: lots of 10ga wire.

Second, I'd definitely use the existing circuits for overhead lights, and convenience outlets. That way all the serious power can be turned off, and no need to use flashlights to see what's going on, or run extensions cords to run a hand-held power tool to do repairs. I've got grandkids, so that was a must for me.

As to the circuit capacities (caveat, I'm not a licensed electrician), I believe that the breaker is sized to protect the wire and outlet devices. Usually tool motors have their own overload protection. As I recall, for short runs, 10 ga wire means a max of 30A, whether 110 or 220, and the outlet needs to be rated for that capacity as well. If you use 20 amp outlets, the breaker should only be 20. That keeps fires from happening in the wiring itself.

The other thing I did was to get a bunch of the plastic outlet plugs used to keep toddlers out of the fixtures. I put one in each unused outlet location. My thought was to keep as much dust out of the outlets, so if I get a spark, it won't start a smoldering fire. I got mine at a dollar store. Much cheaper.

just a couple of 2 cents worth...
Spence

[Roland Chung]

Hi Eric,

I admire your ambition, but this forum may not be the best place to educate yourself about electrical work. I would suggest going to the local big box store and looking for a book about Wiring/Electrical that works for you. Learning from a book would start with the basics and move on to the advanced stuff. At a forum, you will only get answers for the questions that you ask - when starting out in any trade, there will be important answers that you need for questions that you won't even know to ask. For you electricians, the books won't replace the experience of working as an electrician's apprentice for several years, but many woodworkers will never have that oportunity.

That said, I think that the most flexible system would be one that involves having that electrician come in first and install the subpanel and a few strategically placed junction boxes. The electrician may offer you some good ideas based on his years in the trade and he may give you a price to add a few receptacles that is too good to pass up. You could always add to and expand on this, but at least you would be able to examine, closely and first hand, what the pro's do. Sometimes it is better to move in and see how things will run best, before you lock in the locations with your electrical runs.

And in case no one else reminds you, this is a trade where what you don't know can kill you or the people in your shop or burn your shop down. I don't mean to frighten you off, but it would be good to prepare yourself adequately or hire a pro. Good luck!

Roland

[Steven Wilson]

Eric,

You need a to read a couple of books and learn about how things are done in your area. The books you'll need to read, and read, and read, and read again are;

1) A basic electrical wiring book - Sunset, Black and Decker, etc. all make one and they're pretty good

2) A copy of the NEC electrical code; most US jurisdictions rely on the NEC and may be stricter than the NEC, but the NEC is used. You can use a copy at the library but I just decided to get one. It's thick, it's boring, but it's all in there.

3) A book that explains the NEC. These are books that help you interpret the NEC, great info in these but it presuposes that you have a copy of the NEC handy. Also good are some of the building trades books on electrical (like code check electrical).

What you can or can't do will be determned by the relevant authority in your area. Some locations are so strict that a homeowner can't do any electrical work on there own property. Most places will allow the homeowner to work on their own residence but the homeowner will still need to pull permits and have the work inspected. Which brings up -

KNOW YOUR INSPECTOR. In a lot of places the electrical inspector will maintain an hour, usually early in the day, when you can call and ask questions. Ultimately it's your electrical inspector who will say what you can and cannot do.

As for your questions


>Install sub panel (lockable off) for safety and flexability
Good, I would run the sub panel for equipment NOT LIGHTS

>Multiple circuits for lighting - not all on sub panel
Depends, most basements are fairly small, you can probably do it on one, maybe two circuits

>Multiple circuits for electrical outlets (120)
Besides machine circuits two 20A 120V circuits should do

>Multiple circuits for electrical outlets (240)
General purpose or specific machine circuits? I would pull wire to specific 220 machines later

>Separate circuit for DC (cyclone), Compressor (if needed), etc
Yep

>Large tools shoud be limited on the same circuit
Either one tool per circuit or you'll need to be judicious in how you go about assigning these. Your inspector will definately have an opinion on how to do this.

>Single Phase Tools (for the foreseeable future)
You probably don't have 3phase power available. If you want it you'll need to size and install a rotary phase converter. Then you'll be runing a separate wiring scheme for the machines running 3 phase. I would forget this for now.

>Lighting Plan
>8 x 8' (4 x 4' T8 Light Bulbs) - plug in
>8 x 4' (2 x 4' T8 Light Bulbs) - plug in
>Mount one duplex outlet at ceiling height per fixture leaving one socket for >secondary or task lighting as needed

Why? I've done this before but it's just as easy (easier really) to run wire to a junction box, then run armored cable to the light fixture. Spend your money and buy good light fixtures, there is a lot of junk out there.

>Electrical - Initial Thoughts:
>Placed approximately 6' apart
>Alternating a quad 120 outlet and a duplex 120 w/ 240 outlet
>Placed approximately 50" from the floor to the bottom of outlet

All of this is dependent on the code used in your area of jurisdiction. Your inspector may require everything be CGFI. When you've done your electrical rough in (i.e. before sheetrock) you will need an inspection.

Basic Questions:
>How many lights can be on a single circuit
Depends, the calculations are covered in the NEC.

>Can the same set of lights be controlled by three seporate wall switches, I >know you can do two switches
Don't know, consult the NEC, ask your inspector.

>How many outlets (120 or 240) can be on one circuit
Check the NEC, ask your inspector.

>What guage wire is used for 120, 240 for a woodshop
Wire guage is dependant on amperage not voltage. You also need to determine guage based on length of wire, how many wires you have in a piece of conduit, and what you're wiring in. Consult the NEC. In general (and asuming a bunch of things about your situation) 10, 12, and 14 guage wire are used most often.

>Wire run in conduit or Romex, why
I would run general lighting and 120V circuits with Romex in the wall. I would also install some outlets on the ceiling and hook up some pull down cable reels. I like to wire machine circuits in conduit. I also like to use big boxes with lots of volume so I don't end up having box fill calculation issues (read the NEC).


>Is there a standard amp for 120
No, but 20A is fairly popular

>Is there a standard amp for 240
No, and I size my 240 circuits for specific machines, which can be 15, 20, 25, 30, or 50A

>Can I install all 240 lines and run machines at 220, 230
That's already been covered, they're basically the same

>Can something that runs on 20 or 25 amps run off a lie that is 30 amp
Read the NEC, what specific something are you talking about?

>If I run all 240, can I just change the fuses to the needed amp
NO, NO, NO, NO, NO - DANGER WILL ROBINSON - everything is amperage dependent and the most restrictive part of the circuit rules (i.e. you can't put a 100A breaker on 14 guage wire).

[Stephen Dixon]

First I am assuming that you will find an electrician to do most if not all of this work, or at least have him check your work before it is hooked up.

I would leave the lighting on its existing circuit, seperate from the "shop circuits". Nothing like tripping a breaker in the basement, and having all the lights go out to get your attention. Especially when holding a cutoff next to a spinning blade on your radial arm saw. DAMHIKT

You need one circuit for every machine/appliance that starts on its own or operates independently of you, i.e. air compressors, furnaces, air conditioners, dust collectors, air filters, etc.

I would install 4x4 boxes with quad outlets every 4 to 6 feet around the room. Count the number of quads this requires, divide by six, this should be the number of circuits you need for 120 volt outlets. Technically there is no limit to how many outlets you can have on a circuit in a residence, but commercial bldgs. are limited to no more that 13 recepticles on a 20 amp circuit, and I think that is a good limit in a workshop too, hence 6 quads. You can split them up any way you want, some people like a seperate circuit for each wall, some use a seperate circuit for every other outlet, the choice is yours. I have three circuits, every third quad on a seperate circuit. One trick I use to identify circuits is to use brown outlets on one circuit, ivory outlets on the second circuit, and white outlets on the third circuit.

For 220 outlets I would not put in general purpose 220V outlets ramdonly around the shop. I would decide what and where I needed 220V and install circuits for those uses only. If you are working from a subpanel in your shop then it should not be to hard to go back and add new 220V circuits as you need them.

Don't forget GFCIs for every circuit.

Steve

[Mike Cutler]

Eric.

That's a lot of questions.
It is difficult at best to try to give advice on electrical installations over the net. There are too many subtle nuances to the code, and how it is applied in different geographic regions, to have a one size fits all answer.

Your shop is going to be in your basement, not an attached garage or an out building. The wiring really needs to be done top notch. Not that it shouldn't be, no matter where the shop is located, but this is the structure that you live and sleep in. Go quality, and one step beyond.
Work with the liscensed electrician that you hire. Be very honest about what you intend, or think you intend to do. Let him tell you what the physical layout will be.

Two more things that you need to consider prior to construction beginning. Soundproofing, and ventilation.
The noise from woodworking machines can be very loud, and transmit through the floors and walls and drive everyone else out of the house quite easily.
Ventilation. In addition to a dust collector system, you need to be able to ventilate the space to the outside for finishing work and sanding. You will occasionally have to use petrochemical products ( greases, oils, WD-40, mineral spirits, degreasers, etc..) to maintain your machines. You need a way to ventilate externally.
It sounds like your plans will result in a very nice workspace. Go slow,and don't be in a hurry.

[Brian Dormer]

Eric -

"Novices" should not be wiring a shop - or anything else. There's just too many things that you can do that won't be up to code (at best) or downright dangerously wrong (at worst). You could put your life and the life of anyone in the building (like, your family) at risk. You can electrocute somebody, damage equipment or cause a fire (maybe all at once).

Spend the money to hire a competent, licensed electrician. If you ask nice - s/he may be willing to let you help (there's lots of "grunt work") and you can learn from the experence.

bd

[Rob Will]

Eric,
A few thoughts on your electrical.

To operate lights from 3 or more locations you need 4-way switches. You use 3-way switches at the ends of the run and then add 4-way switches in the middle to get as many control stations as you want. All you need is the appropriate 3 conductor wire between ALL of these switches.

Size breakers to protect your wire. Some very general considerations.
15A breaker = 14 ga wire
20A breaker = 12 ga wire
30A breaker = 10 ga wire
Remember this is not circuit capacity, just breaker size.
In your project voltage does not matter for breaker and wire sizing.
Distance matters.
Full load amps matters.
Motor starting current matters.

Sub panel: Excellent idea. Go ahead and get a good one with Copper buss bars instead of aluminum. I have seen several buss bar failures with cheap panels. Remember that a true sub panel requires a separate neutral and ground back to the main panel thus you will have 4 wires total. You do not bond the neutral and ground together in a sub panel.

Wiring devices: Use heavy receptacles and switches mounted in deep boxes.

Wires to receptacles: If you can run dedicated wires from each receptacle back to an accesible junction box near the sub panel, you are better off in the long run. Individual runs can be changed to 220v as needed if they are on a separate wire. Many electricians like to "daisy chain" receptacles. Naturally this is faster and uses less wire but you can't change anything without tearing the wall out. I often use a combination of these two methods.

110 vs. 220: Any time you have a choice, wire the motor to run 220v. Remember AMPS are what count and 220 runs half the amps of 110 doing the same job.

Lighting receptacles in ceiling: Excellent idea. This allows you to quickly disconnect a fixture for service etc. One receptacle can serve two adjacent fixtures ehh?

Something to consider: Electric motors have a huge current draw upon startup. This is yet another reason to go with dedicated heavy wire and breakers to key locations. As others have mentioned, some motors have their own overcurrent protection. This is NOT to protect the wire, the breaker does that. Larger motors usually have a magnetic starter with built-in motor protection ("heaters"). Now speaking of current in-rush, sometimes normal circuit breakers have trouble with motor starting without tripping. Sometimes special circuit breakers called "motor circuit protectors" are used but these are big and expensive. Don't worry about this too much for now.

I think your planning so far is VERY good and your stated intention of hiring a pro is also a wise idea. However, I have seen a few "residential" types that would be challenged to wire your shop correctly. (We are not talking about running a bathroom fan here). Local electric motor shops usually have in-house electricians or know of some pros with industrial (motor) experience. Your project is a bit complex for the borgs or the DIY books.

Your detailed planning will make the electrician's job a lot easier. I would suggest making some labels of proposed tool, receptacle and switch locations and do a walk-through.

Go ahead and buy that 220v 3hp Unisaw so the electrician can see what you are getting into.

Rob

[Bill Fields]

See Jim Becker post--read twice--get help.

If you launch without direct from day-one help from an electrician, the eventuality (sadly) is that you likely could have to tear it all out and pay someone to do it anyway.

I am an Electronics Engineer--but not even close to being an Electrician. Very different skillsets.

I wired my former 5 story house for all new 200 amp 110/220 with electric baseboard heat, etc. a few years ago, but when I needed to get some distribution and outlet upgrades, I gladly hired a retired electrician and it cost $700. Some of that work consisted of re-wiring a few real "rat's nest" boxes I had put in.

Think of your home burning down and your insurance company laughing at you when you put in the claim.

Bill

[Norman Hitt]

Eric,
A few thoughts on your electrical.

110 vs. 220: Any time you have a choice, wire the motor to run 220v. Remember AMPS are what count and 220 runs half the amps of 110 doing the same job.

Rob

I felt a little Clarification for the Reader to the above statement was in order, as this is probably one of the most commonly misquoted, or Rather, "Misunderstood" facts about electrical circuits. Any motor (except for a few SPECIALLY BUILT Motors with different windings), will use the "Same TOTAL Amps" whether running on 110V OR 220V. The difference is that it is ALL on ONE Hot leg of a 110 ckt, and it is SPLIT between TWO Hot legs on a 220 ckt.

For example, a motor's label that shows 15 A@110V / 7.5A@220V does NOT mean that the motor will only use 7.5A TOTAL when running on 220V, because in the 110 ckt there is one HOT wire (supplying ALL 15 amps), one Neutral wire, and one Ground wire, whereas in a 220 ckt, there are TWO HOT wires (Each supplying half of the 15 Amps), and One Ground wire, (no neutral).

Therefore, running on 220V Could Possibly allow one to use a smaller guage wire rated for the reduced amp requirement per leg if so desired, but I wouldn't, (I'd rather have the extra "Safety Cush" and less chance for a voltage drop over a long ckt run). I wouldn't even consider changing any motor to 220V unless it is larger than 1 hp, and probably only above 1 1/2 hp, as the motor will not notice the difference of 110 vs 220 as long as the wire guage is sized appropriately for the amp draw, and there is NO SAVINGS on electricity used.

Hope this helps.

[Eric Shields]

Phew, nothing like a little light reading on a Sunday morning. I'll be thankful that I can do it at work and not take any time away from my family to fulfill my "planning needs."

Thank you all for responding with your knowledge and opinions.

I knew when I posted this it was asking a lot of y'all. But, in what I have come to believe to be true Creeker fashion, you shared your knowledge enough to get me started. On that point, I would like to reiterate that I am only putting pencil to paper in order to get a concept of what I want to discuss with a cirtified electrician. I won't be pulling any fixtures, reconnecting any wire, or running anything new (wires or outlets) prior to this initial discussion. I just wanted to be capable enough to discuss with a professional what I wanted/needed from his/her services. Once that is accomplished, and a solid plan is in place, I do intend on doing as much grunt work as possible to help defray this cost.

I was planning to get a basic electrical wiring book within the next few days, however will probably get one today as I'll be visiting one of the big box stores to deal with an unexpected wood floor issue (different topic, different discussion, thankfully its something I'm more than comfortable with). This will, in no doubt, help further my education that this discussion has started. As I knew before, and now even more now, this is too important and complicated task to tackel with my limited knowledge. But thank you once again for answering my basic questions.

Eric

[John Wilson]

Working for an Electrical Engineering firm and designing power circuits on a daily basis, I would suggest like others have already said that you get a licensed Electrician to do the work or at least one to oversee any work that you do. That being said, in accordance with the NEC, circuit breakers must be derated 80% (max 16 amps on a 20A circuit, 24 amps on a 30A circuit, etc.). Just add up the loads that will be connected to a single circuit, multiply the total by 1.25 and use the next highest standard size circuit breaker. Duplex 15 and 20 amp receptacles are calculated per code at 1.5 amps each or a maximum of 12 on a single 20 amp circuit. As a matter of practice I never connect more than 8 receptacles to a single circuit. All other equipment (excluding lighting) should be fed with dedicated circuits. Run a ground wire (very important!) with all circuits and insure that the sub panel is grounded properly upstream. This will go a long way to keep you from killing yourself. Don't use cheap lighting fixtures with magnetic ballasts. Buy fluorescent fixtures with electronic ballasts and T-8 lamps. Be careful with advice received from the big box sales reps. In many cases they know less than you do. Good Luck!

[Rob Will]

Therefore, running on 220V Could Possibly allow one to use a smaller guage wire rated for the reduced amp requirement per leg if so desired, but I wouldn't, (I'd rather have the extra "Safety Cush" and less chance for a voltage drop over a long ckt run). I wouldn't even consider changing any motor to 220V unless it is larger than 1 hp, and probably only above 1 1/2 hp, as the motor will not notice the difference of 110 vs 220 as long as the wire guage is sized appropriately for the amp draw, and there is NO SAVINGS on electricity used.Hope this helps.

Norman, I agree. I was also thinking about those 1 HP and up motors. All too often we see tools in the 1 to 1-1/2 HP range that are crowding a typical 120V circuit. I hope this was not taken to imply electrical savings or wire downsizing. Thanks for making this clear.

Rob

[John Wilson]

This is just an FYI comment meant only to clarify voltage ratings. There is no such thing as 110 and 220V. The transformer that serves your home is rated 120/240 volts and if you use a true RMS voltmeter and measure it you will find that to be true within a couple of volts plus or minus. Utility power companies general distribute residential power plus or minus 10%. Single phase motors that run connected to two phase conductors (single phase 240V are rated 230V).