My father in law just moved into a retirement condo in Connecticut that has a basement and he wants to set up his woodworking shop down there. Right now the basement is serviced by one 20 amp circuit breaker from a 200 Amp Murray panel that feeds a total of 4 incandescent ceiling bulbs (one on a switch from the stairs, 3 on pull chain porcelain fixtures) and one duplex outlet. There are no empty circuits in the main panel.
On his inspection (he used to be a chemical engineer during is working life so he knows a little), he said that when he took the cover off he didn’t see any take-off lugs where he thought a secondary 100 Amp panel could be connected. He wants to have enough power and circuits for his tools (all 110 volt with, probably, at most a 10-12 amp motor for his contractor’s table saw being the largest). At most, aside from general and task lighting, he’d be running one tool, a 1.5 Hp Delta Dust Collector and a ceiling mounted Delta Air Cleaner (? Hp) so his electrical needs at any one time are fairly modest. Oh, and during the summer months, a dehumidifier would also probably be running (although that could be temporarily turned off if necessary).
While he’ll be hiring an electrician to actually install the panel and do that wiring, he didn’t want to wind up with a service charge to be told it can’t be done if he can avoid that.
Anyone familiar with Murray panels and know whether they provide a means to take a power feed for an auxiliary box or not? If they don’t, does Code preclude hooking up two wires to the inlet lugs where the main power supply comes in or at some other point within the box?
Any suggestions short (oops, sorry I said that) of replacing the entire main panel? Any thoughts on the best auxiliary panel to purchase? BTW, this extra wiring is, apparently, legal within the condo if done professionally by a licensed electrician.
Thanks.
Replies
Did he say how many spaces there are in the panel in total? It seems unusual for the electrical loads in a condo to fill up every single space of a 200 amp panel. When they built the place they must have put in the smallest panel they could find.
It *may* be possible to consolidate some loads to open up a couple slots, and then he could put in a two pole feeder breaker that would supply power to a subpanel for the basement shop. I'd say the first thing to do would be to determine what the current actual load on the panel is, to make sure there's enough capacity for his power tools. He'll probably need an electrician to do that sort of thing. For the amount of tools he'll be running a 60 amp subpanel would probably be more than adequate.
One other thought...since he's in a condo, are there any association rules that may get in his way? They may have limitations on workshops or noise, that sort of thing.
If he can't use tandems, then he can install a small sub-panel by the existing panel and move a couple of circuits to the sub-panel and free of space for breakers for the new sub-panel and ones for the sub-panel in the basement.
Also note that panels have a rating for the maxinum number of slots and the maximun number of poles.
If his is something like 30/40 that means that it has a maximum of 30 slots, but that 10 of them can have tandems. That info should be on the lable.
Now some panels do alone for feed through, which this one apparantly does not. But when you do that the wires need to be rated the same as for the main panel, eventhough you use a smaller sub-panel.
Also I have been using the term main and sub-panel. But beening that this is a condo I suspect that there is main disconnect someplace outside where the meters are. Thus the "main panel" is actually a sub-panel. In that case the feeder wires are protected and I *think* that it would be possible to run a branch to the basement panel.
But I doubt that the "main" breaker (in the condo panel, if there is one) is rated for 2 sets of wires. Likewise the main disconnect.
Murray panels are the type that take so called generic breakers. The code will allow up to 42 circuits in one panel. You can probably obtain some half-space breakers [1/2"] and replace the existing breakers[1"] to make space for a new two pole breaker to feed your new sub panel. Make sure that the replacement breakers are U.L. listed for installation in Murray panels.
You can buy non listed breakers that will fit and work, but in a condo situation, I would want to be covered[liability-wise] in case of future problems.
I'm sure the project can be done . Most can, if you only throw enough money at it.
"The code will allow up to 42 circuits in one panel. "But no more than what the panel is listed for."Murray panels are the type that take so called generic breakers."Why not just Murry breakers and be sure?
OK, thanks guys. I read all 4 responses and I don't know the answers to all of your questions right now. I do know that noise and use won't be an issue as long as machinery is not installed outside (e.g., like the dust collector dust bag). They're on an end unit of 3 homes (only the end units have basements) and his work area is planned along the outside end of the basement wall. And, I'm told the President of the Condo Board has an even more generously equipped wood shop in his basement, so I guess if he can do it, anyone can. Besides, when I read them I didn't see anything in the condo docs that specifically prohibited it. No businesses of course, but that's not an issue.
I'll stop by the condo tomorrow and inspect the panel in the basement to see if I can figure things out a bit more. I printed all your responses so I'll hopefully be able to look for the info needed to answer your posts. If need be, I'll snap a couple of photos and post them if that seems to make sense.
But, at the start, I like the idea of replacing a 1" single throw breaker with a double throw for some of the pre-existing circuits and opening up some of the places within the panel. That avoids the necessity of the extra work involved in wiring up an auxiliary panel (if that is possible here) and might be far less expensive if there is sufficient room for the extra # of circuits. On my way home from work, I stopped off at my local Home Big Box - needed light bulbs anyway - and saw that a Murray 2 pole was selling for $9.97 (for both 15 amp and 20 amp). GE 2 poles were the same price except for something called a "non-limiting" breaker which cost $14.50. Didn't write down the price of Square D breakers. GFCI breakers were about $31 for both Murray and GE (but, of course, they were single pole only). So, the cost of the breakers is practicaly negligble.
I don't know how many circuits are in the panel now or how many are allowed, but I do know that some are for extremely light loads (e.g., wall outlets for lighting in the LR is one 15 A circuit [5 duplexes] and lighting in the DR [one ceiling fixture - no outlets] is another 15 A circuit!) They have central air on its own circuit so window a/c's are not an issue. The kitchen has 2 circuits for counter top appliances and only two outlet boxes (each a double duplex) for counter top appliances! And, no GFCI breakers for either the kitchen or the bath (although the one bath outlet is a GFCI on its own 15A circuit with an exhaust fan and two lamps.)!
I don't know who did the wiring but I think they probably got overpaid for doing nonsensical work or the architect who designed the system was a dummy. Or both.
More tomorrow. But thanks a lot so far. Really great info.
Just another thing to think about. One reason that it would be good to pay the $100 or so for a service call is that the electrician can determine if the feeder wire is sizer sufficiently to handle the additional load.
I have seen instances where an older panel was changed out to a 200 amp panel with no regard to feeder size.