Y'all go ahead and laugh, now! :)
I don't think it is apparent to the average person just how much
experience and knowledge is behind that information, particularly with
regard to the sub panel choice/type.
Trial and error on this issue can cost the neophyte beaucoup $$ ...
Okay, Okay, I WILL DO as Lew suggested--and gladly too! : ) : )
Install 2P-30A branch c'bkr for each 240V stationary tool along with
a 2P-30A, non fused disconnect at (within 10ft) the tool.
Question: So this redundancy is a good idea for 240v tools, but is not
as important for ones powered at 120v (which are even more likely to be
powered by conventional outlets wired in a series)?
And a separate circuit for every stationary tool unless you're a
production shop w/ an employee at every workstation continuously through
a shift is _WAY_ over the top overkill...
For a home, casual-use workshop as I gather this is, one or perhaps two
30A 240V circuits will be enough w/ outlets judiciously placed for the
major equipment you now have and some consideration given to what you
think you may want to add in the foreseeable future. You, as an
individual can never be using more than one at a time so, other than the
one tool, the only other loads active simultaneously will be the
potential DC and maybe a compressor.
Circuits for electric heat, etc., should, of course, be separate.
The "non fused disconnect" at each tool is, in ordinary terms, the plug
on the end of the power cord.
There may be one advantage (albeit slight) to wiring a "dedicated
circuit" for a stationary tool, particularly in shops in "garages" ... a
"dedicated circuit" is exempt from being GFCI protected in many locales.
At one time in the early days of GFCI, it was worth doing so as to not
have to deal with nuisance trips, which are no longer the problem they
That _is_ one of the later NEC items I do tend to ignore in
non-wet/indoor locations like a shop...probably the most common one , in
Bill should, of course, follow local Code requirements (disclaimer :) )
Having recently purchased my home, I think it is the case that our local
code (central IN) requires GFCI on outlets within a short distance of a
sink/bath except older homes may be grandfathered out of this
requirement. However, needless to say, I am not an expert.
iwires post from "mike_holts" forum, copied and pasted below
(it makes interesting reading...). --Bill
I will post the code rule for GFCIs in basements below but the short
version is 15 and 20 amp 120 volt receptacles must have GFCI protection.
You have a few options.
1)Install a 2 pole 120/240 GFCI breaker at the panel and protect both
the 120 and 240 outlets.
2)Use a standard 2 pole breaker at the panel go to your 240 outlets
first then install a GFCI outlet at the first two (each leg of the 3
wire cable) 120 receptacles and protect all receptacles down line with
3)Use a standard two pole breaker at the panel and go in any order with
the 120 and 240 outlets but install a GFCI outlet at each 120 volt location.
IMO keep the 240 outlets on a separate breaker, by the time you jump
through hoops to do this you will have spent as much as running a 2 wire
home run for the 240 outlets.
Here is the code rule.
210.8(A) Dwelling Units.
All 125-volt, single-phase, 15- and 20-ampere receptacles installed in
the locations specified in (1) through (8) shall have ground-fault
circuit-interrupter protection for personnel.
(5)Unfinished basements for purposes of this section, unfinished
basements are defined as portions or areas of the basement not intended
as habitable rooms and limited to storage areas, work areas, and the like
Exception No. 1: Receptacles that are not readily accessible.
Exception No. 2: A single receptacle or a duplex receptacle for two
appliances located within dedicated space for each appliance that, in
normal use, is not easily moved from one place to another and that is
cord-and-plug connected in accordance with 400.7(A)(6), (A)(7), or (A)(8).
Exception No. 3: A receptacle supplying only a permanently installed
fire alarm or burglar alarm system shall not be required to have
ground-fault circuit-interrupter protection.
You may be spot on this. I only do commercial industrial so I'm not
right up on residential but I believe all garage circuits require gfi.
There are exceptions for appliances and dedicated circuits. May be a
drawback garage shops, but I think most repair shops are now required
to have gfi circuits.
We are required in most municipalities where I build to have GFI
protection on all "wet area" receptacles ... this includes bathroom,
utility rooms with sinks, kitchens, garages, sun rooms with drains, and
all exterior receptacles.
We are also required to have AFCI protection on all dwelling bedroom
On the latter, I've had homeowners who are selling a home I built when
AFCI wasn't required, or even available, and during the sale process
failed a buyer's third party inspection because lack of AFCI protection,
I've gone back and had the electrical contractor install them at our
cost ... seems like good business, and a prudent thing to do in this
I can see where thats good business. The more people that have
something good to say about how you do business is good for repeat and
referal customers. A good reputation leads to a lot more negotiated
business and being able to sell on quality and fair price instead of
just a small caveat to this statement, as I had to consider this in my
shop. Both a given power tool, perhaps the table saw, and the dust
collection system will probably be on the same time. Be sure to add both
loads together to make sure a circuit is large enough. Oh, and don't
forget that your air compressor will more than likely kick on at this
inopportune time as well.
Uhhh, _excuse_ me??? The part you so judiciously snipped continued...
"so, other than the one tool, the only other loads active simultaneously
will be the potential DC and maybe a compressor."
For 30A/240V, 10A each will be in the neighborhood of 3hp FLA motors. I
submit for the home shop dude just getting going as is OP he'll have far
more than enough...
If'en he's going w/ 5hp PM and an Oneida central DC, well ok but I don't
get that feeling here, do you???
When I wired my garshop I did two separate 240v circuits; one runs the
dust collector and the other the table saw and a 5hp compressor (neither of
which ever runs congruently). How often do you run more than one device at
Additionally, I ran four 120v circuits, two for power tools with
each wall having a mix of both circuits and a single circuit each for the
freezer and a "beer box."
Dave in Houston
Following up on your hints, I came to learn that a service outlet offering
50A service is different than one offering 20A or even 15A service (although
the 20A outlet, 6-20 is compatible with 6-15). The Grizzly G-0690 TS I am
considering has a 6-20 plug (NEMA 6-20P). ; )
What a day.
Is there a rule that says a subpanel has to be a very short distance from
the main panel? I would position it about 10 feet away if I could.
Is anything (code) likely to prevent me from doing what I want with 15A and
120v and 240v circuits from a subpanel (like having 10 of them)? As you
I'm likely to stay far below the 50A threshold in terms of actual usage.
Thank you for the lesson!
No, that's what subpanels are for -- just size it for the number of
circuits of the type you want/need and make it's service breaker the
same or smaller than the feed. If it's close enough, you can (I think)
get by w/o the local breaker/disconnect but it's certainly more
convenient and I'd likely not scrimp...
Good luck, it ain't rocket science; most of the Code is simply
formalizing what is common sense; it just takes somebody to point out
what that commonsense is for the first time and NEC is the standard.
The self-help books are pretty good in general at separating the code
legalese and turning that into what actually needs doing...
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