Wiring a new addition

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  #1  
Old 06-08-02, 10:18 AM
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KevinA
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Question Wiring a new addition

I had a 625 sq ft garage w/ a 500 sq ft bonus room added on to the house. I have most of the outlets, switches, light fixtures, etc, already wired with the wire for each circuit run to a location where I plan to add another panel. I'll be running wire from the main panel, about 75 feet away, to feed the new panel.

What capacity should my new panel be? I'm thinking at least 50 amps. -?

What wire size should I run to feed this new panel? It'll be run under the house- does it need to be in a conduit?

Grounding the new panel- Can I just ground it to the main panel?

Thanks.

My 1st post here. Cool site- lots of good info.
 
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Old 06-08-02, 10:43 AM
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Code is only going to require a single 15-amp 120-volt circuit (i.e., 1.8 KW). Anything you add above that is strictly for your own convenience. It all depends on what you plan to do in that garage and bonus room. Unless you plan a pretty hefty shop, 50-amps is more than enough (i.e., 12KW).

6-gauge copper wire (three insulated conductors plus a grounding wire) will be fine. If you use 6/3 UF cable, conduit is most likely not required. But check locally as there are local variations to the NEC.

If this is an attached structure, the grounding wire betwen panels will be all the grounding you need. Keep all the neutral and grounding wires isolated from each other in the subpanel.
 
  #3  
Old 06-08-02, 12:46 PM
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You really don't need to spend the money on a sub panel in this situation. You may run your branch circuits directly to the main service rated panel much easier and cheaper in my opinion. See no advantage to install a sub panel in what you discribe.

If you install the sub panel do not install a new grounding electrode at that sub panel. You must install a 4 wire cable with a neutral and an equipment grounidng conductor in that feeder. YOu may use 6 awg "lot wire" "metal clad cable" or an "SER" cable as your feeder to a sub panel. Any of the above can be bought in 4 wire cable style and is much easier than installing conduit.

Unless you have machinery fastened in place in that garage you should be fine with 2 circuits 12/2wGrnd from the main service panel without any sub panel. Onc 20 amp circuit for your room addition and one 20 amp circuit for your garage. The NEC allows both to be on one single 20 amp circuit if you wanted to wire minimum wiring design allowed by the NEC.

Hope this helps

Wg
 
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Old 06-08-02, 03:49 PM
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The main reason I planned to go with a sub-panel was to keep from having to run separate lines for each circuit all the way to the main panel. That, and my main panel only has 2 available slots left. (Actually, they're only available because of a baseboard heater that was removed.) Is there anyway around that w/o upgrading the main panel? ie-what if I need an additional circuit later?

If I do stick with the separate panel idea- Would a 50 amp panel be over-kill? I was thinking that size just due to my air-compressor which needs almost 15 itself.

Thanks for the help.
 
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Old 06-08-02, 04:01 PM
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Given the additional information that your main panel only has two slots left, I think Wg would not have recommended against the subpanel.

Yes, 50 amps is overkill. But who knows waht you might want to do in the future. Remember, 50 amps at 240 volts is equivalent to 100 amps at 120 volts. So a 50-amp subpanel can probably comfortably support about a dozen 15-amp circuits. Given that you only currently need two or three, a 50 amp subpanel gives you lots of room for future growth ... in case you take up welding in the future.
 
  #6  
Old 06-08-02, 04:17 PM
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John is right about not knowing about the panel being full and you also added info on a load in the garage that you did not mention about an air compressor.

What size motor and what voltage is that air compressor?

Also if you panel is that full will it take 50 amps added to that main panel?

How many breakers are in that main service rated panel and what size it the main service serving you home?

Look on the inside of your panel's door at the list of branch circuits. See if you have an "a" and a "b" on each circuit. This will tell us more about your panel that we need to know.

Also do you have any other larger loads you are planning in the room addition or garage?

Curious

Wg
 
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Old 06-08-02, 04:49 PM
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Sorry, should've mentioned everything the 1st time.

What size motor and what voltage is that air compressor?
It's 5.5hp, 120v. Not that big.

How many breakers are in that main service rated panel and what size it the main service serving you home?

Look on the inside of your panel's door at the list of branch circuits. See if you have an "a" and a "b" on each circuit. This will tell us more about your panel that we need to know.
There's a box outside next to the meter that is a 200 amp box w/ circuits for the HVAC, water heater, hot tub, range, etc, and one for the inside panel. It has 12 slots, all full (6- 240v circuits). Inside there is a 150 amp box with 20 slots in it- all full, except the 2 available from the deletion of the 240 baseboard heater.

There's 'a' and 'b' on spaces 11-20. Does that mean I can add more of those 1/2 sized circuit breakers in there? There is a couple of those. If so, is doing that a good idea?

Also do you have any other larger loads you are planning in the room addition or garage?
No, the compressor will be the largest load.
 
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Old 06-09-02, 08:32 AM
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Half sized breakers

There's 'a' and 'b' on spaces 11-20. Does that mean I can add more of those 1/2 sized circuit breakers in there? There is a couple of those. If so, is doing that a good idea?
Yes you can add more half sized breakers and there is nothing wrong with doing so. Just make sure that you use the same brand and type of breaker as the ones shown on the panel labels or that you use one that is classified for use in that panel. Classified breakers have an insert packed with them that list the panels in which they are tested for use.
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  #9  
Old 06-09-02, 12:59 PM
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Sounds like you have one heck of a lot of breakers and loads listed all being pulled from one 200 amp main service rated box. You might soon be experiencing tripping of your main breaker of blowing you main fuses in that 200 amp main service rated box. If that happens you will have overloaded that 200 amp main service rated panel. Sounds like you are close to an overload or are overloaded and just been lucky. If you want to perform a demand load calculation to see if you main service panel is overloaded per the NEC minimum serice rated amp size try the following link that show a format to perform that demand load calculation.

http://homewiring.tripod.com/homewir...DmdCalc02.html

Hope this helps

Wg
 
  #10  
Old 06-09-02, 02:05 PM
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Originally posted by Wgoodrich
Sounds like you have one heck of a lot of breakers and loads listed all being pulled from one 200 amp main service rated box. You might soon be experiencing tripping of your main breaker of blowing you main fuses in that 200 amp main service rated box. If that happens you will have overloaded that 200 amp main service rated panel. Sounds like you are close to an overload or are overloaded and just been lucky. If you want to perform a demand load calculation to see if you main service panel is overloaded per the NEC minimum serice rated amp size try the following link that show a format to perform that demand load calculation.

Hope this helps

Wg
Wgoodrich
I don't see the problem. A two hundred ampere service will have 40 or 42 slots in the panel if it is mounted in a single enclosure. In some parts of the country local codes require an external disconnecting means for the interior wiring. This is often accomplished with a two hundred ampere, main lug only, twelve slot, outdoor panel or with a 200 ampere main breaker panel that has between eight and twelve breaker slots and feed through lugs.
The use of these exterior service disconnecting means is also considered good fire protection practice in rural properties to assure continued operation of the well pump during a fire in the home. This assures the continuity of water supply for fighting the fire while awaiting help from the fire and rescue service. You will also note that up until quite recently field installed service equipment was not permitted to be installed in or on a manufactured home.
The interior distribution panel is a 150 ampere panel with a twenty by thirty breaker buss architecture. If both panels are filled to the max you would have a total of forty two breakers and that is a perfectly normal number of breakers for two hundred ampere service. His present situation is twenty breakers inside and six double pole breakers outside. It would seem he would have a way to go before even approaching the forty two breaker mark.

The use of two hundred ampere MLO panels coupled with the conversion of existing panels from service equipment to distribution panels is a cost effective way to do heavy ups in existing properties. The existing panel is retained but its heavier 240 volt loads are moved to the new exterior panel. A second panel is then added to provide additional breaker slots with the total being held to forty two total over current devices not including the main.
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  #11  
Old 06-09-02, 08:15 PM
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Tom, I really do not care if a person has 150 breakers being pulled off a 200 amp panel if they only have general use receptacles and general use lights on that list of breakers. However when you start adding connected loads such as the person posted on previous replies in this post you are adding up well past 200 amp demand load. The number of breakers only told me that either someone put 2 receptacles on a circuit or this house has more than 2000 square feet. Then add a 60 amp heat pump, 40 amp electric range, 60 amp hot tub, and a 30 amp water heater to that demand load as this person mentioned we now have a suspected overloaded panel. If you follow the rules of the NEC concerning 4 or more fastened in place appliances allowing a 25% reduction to that connected load you still already have 150 amps on those four listed fastened in place appliances. Now a 5 horse power air compressor is mentioned again a fastened in place appliance. If a demand load calculation is performed as required in 220 of hte NEC I suspect you will find this persons 200 amp service is quite a bit too small in amp rating to carry the loads mentioned not including the 3 volt amps per square feet required for general lighiting and the 3000 volt amps required for the small appliance branch circuits and 1500 more volt amps required for laundry. Then remember a circuit for baseboard heat was de-energized. How many more of those breakers are carrying fastened in place heating units.

Tom, it does not matter even if you put a 100 breakers in main panels and sub panels carried through that main service rated disconnect or panel. What matters is the required demand as dictated by Chapter 2 of the NEC which sets the minimum service size allowed.

Tom you did make a comment that bothered me I think. Were you referring to an installation of a MLO panel used as a main service rated panel without a main breaker or disconnect form using more than 6 breakers as main breakers in that MLO panel used as a main service rated panel? This would be a life safety issue you should be concerned about if I read you right. YOu are limited to 6 main disconnect forms serving the same building unless you are in large industrial settings. Did I read you right that you were talking of a main panel without a main breaker?

hope this helps

Wg
 
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Old 06-10-02, 08:56 AM
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It couldn't hurt do the load calc. I'd be curious to see what I came up with anyway, so I'll go through it and let you know what I get.
 
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Old 06-10-02, 09:12 AM
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Assumptions again

I was not trying to be quarelsome when I said I did not see a problem. If you perceive that flavor in my reply it was completely unintentional. I did not mean to misconstrue your answer as being based only on the breaker count. My reaction was based on my familiarity with that particular type of installation being very common in agricultural and Southern Building Code installations. For reasons I have already laid out elsewhere these "two panel" installations are very popular with fire protection people and are quite common in some parts of the country.

Now as to the use of MLO panels as service equipment please read my entire answer. I feel I am being battered with assumptions. I specifically said twelve slot MLO.
This is often accomplished with a two hundred ampere, main lug only, twelve slot, outdoor panel or with a 200 ampere main breaker panel that has between eight and twelve breaker slots and feed through lugs.
A twelve slot MLO will except six double pole breakers. If one or two of these breakers feeds the interrior panel/s and the others are used for other larger loads the installation is fully code compliant and very cost effective.
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Old 06-10-02, 11:39 AM
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The full-load current of a 5HP 120 volt moter is almost 60 amps.A starting current of 300% FLA would be 180 amps.
 
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Old 06-10-02, 11:41 AM
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Tom, I do not believe that I could approve a 12 circuit MLO panel being used as a main service rated panel. If this was an MDP panel with 6 buckets, I can see you design as suggested. However a 12 circuit panel also allows 12 single breakers also in that same panel. While it is true that 6 double pole breakers installed in a service rated panel installing a 12 circuit MLO panel with only 3 or 4 double pole breakers in that panel installed leaving several circuits open for single pole breakers would be inviting the installation of more than the six max main breakers allowed. I would be hard pressed believing a 12 circuit distribution panel MLO without that panel being full of breakers is designed to limit the maximum 6 disconnects allowed.

I probably would accept an MLO service rated panel that is full of 6 double pole breakers being used with that panel allowing no more breakers being installed. If I inspected a MLO panel 12 circuit with single circuits left for future use I would require a main breaker or disconnect form.

My opinion is if you install an MLO panel service rated with only enough circuits for future use not to exceed the total of 6 movements of the hand then I would pass it. Otherwise I would see a 12 circuit main service rated distribution panel without a main breaker. The extra circuits available allows the 6 disconnect limit to be exceeded.

If you want to install a MLO panel then purchase an MDP panel with 6 buckets. Then the 6 sweeps of the hand is limited allowing for no questions by the inspector. That would be my suggestion. Otherwise if you leave unused circuits in that panel that would allow the 6 disconnect rule to be exceed you are opening yourself up to the unknowing to add single pole breakers exceeding the 6 disconnect rule and if something happens causing damage or harm you would be liable to those damage costs or harm costs.

Wg
 
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Old 06-10-02, 10:55 PM
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Code or opinion.

Originally posted by Wgoodrich
Tom, I do not believe that I could approve a 12 circuit MLO panel being used as a main service rated panel. If this was an MDP panel with 6 buckets, I can see you design as suggested. However a 12 circuit panel also allows 12 single breakers also in that same panel. While it is true that 6 double pole breakers installed in a service rated panel installing a 12 circuit MLO panel with only 3 or 4 double pole breakers in that panel installed leaving several circuits open for single pole breakers would be inviting the installation of more than the six max main breakers allowed. I would be hard pressed believing a 12 circuit distribution panel MLO without that panel being full of breakers is designed to limit the maximum 6 disconnects allowed.

I probably would accept an MLO service rated panel that is full of 6 double pole breakers being used with that panel allowing no more breakers being installed. If I inspected a MLO panel 12 circuit with single circuits left for future use I would require a main breaker or disconnect form.

My opinion is if you install an MLO panel service rated with only enough circuits for future use not to exceed the total of 6 movements of the hand then I would pass it. Otherwise I would see a 12 circuit main service rated distribution panel without a main breaker. The extra circuits available allows the 6 disconnect limit to be exceeded.

If you want to install a MLO panel then purchase an MDP panel with 6 buckets. Then the 6 sweeps of the hand is limited allowing for no questions by the inspector. That would be my suggestion. Otherwise if you leave unused circuits in that panel that would allow the 6 disconnect rule to be exceed you are opening yourself up to the unknowing to add single pole breakers exceeding the 6 disconnect rule and if something happens causing damage or harm you would be liable to those damage costs or harm costs.

Wg
I would suggest that you consider the logical implications of your position. Is any installation that could later be abused a code violation? Imagine a six foot long service trough with only two disconnects below it. Could I not install the panel you are suggesting below it after inspection thus violating the six throw rule. Would you turn that installation down because the troughs length makes it possible to install two many disconnects below it. If I installed a back fed main breaker with a listed anchor kit to serve as the main breaker to a utility building's separate service would you turn down the installation because I might remove the back fed main breaker and use the main lugs instead after inspection. Could I not pull the meter on a main breaker panel and install a main lug conversion kit after inspection. Why not turn down all main breaker installations and require a separate disconnect. What about the main breaker panel with twelve slots and feed through lugs? If I planned ahead I could change the service conductors to the feed through lugs after the inspector left and have a total of thirteen breakers directly connected to the service entry conductors. I would then connect the load that had been connected to the feed through lugs to the main breaker terminals thus exposing the service conductors to a failure causing overload. Would you turn dow that installation based on that possibility.

This is the same logic that says we must not use multi wire branch circuits because unqualified persons may be injured by opening the neutral. At one time the Canadian Electric code required service panels in residences to have a separate dead front over the supply connections to prevent harry or harriet homeowner from coming in contact with the live terminals and in order to remove the rest of the dead front you had to open the main beaker. Should we be doing that here? Should all of our residential panels be fed from a separate enclosed breaker with a shunt trip connected to the panel cover? Should the separate enclosed breaker be located facing the street so that the police can observe and report any tampering? The fire prevention code in some communities requires that for fire protection water supply post indicator valves.

Twelve slot MLO panels are available listed for use as service equipment. Even twelve by twenty four buss architecture panels are available with service equipment listing. The label does have instructions that limit the number of breakers installed to six or less when used as service equipment without a main breaker. If I installed a service equipment listed panel with less than six breakers in it and I got turned down that would be the third time in thirty five years of electrical work that I would process a formal appeal. I have a high level of confidence that I would win the appeal. As I said in a previous posting the Maxim of the law is that silence is consent. What the code does not forbid it allows.
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Old 06-11-02, 06:26 PM
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Looks like I irritated you a bit. Sorry to have said something different from what you want to believe causing your irritation. That is not my intent. My intent is only to promote knowledge of the rules as written in the NEC. The discussions in this forum are intened to help others and to seek the true intent of the written word of the minimum safety standards as written in the NEC. That is my goal is to seek and promote knowledge not to irritate. I mean you no harm just trying to help.

Rules in the NEC are minimum safety standards. Bending those rules to meet what a person wants to believe or imply is not good safety practice. If a 12 circuit mlo panel is being used as a main service rated panel with enough remaining open slots to install more than six throws of the hand a violation of the maximum six disconnect rule would be present in my opinion and I would and have rejected that type installation as a code violation of the 6 disconnect rule.

I believe a person would be hard pressed to prove successfully either in an inspection appeal or through a judicial system that having a 12 circuit Main Lug Only panel used as a service rated panel having enough spare single unused branch circuits spaces still available in that MLO panel to violate the maximum 6 disconnect rule is within the minimum safety standards set by the NEC. I suspect a ruling of an inspector having refused to approve an MLO panel used as a main service rated panel with enough spare circuit left available to violate the maximum 6 diconnect rule would be upheld in any hearing challenging that AHJ's ruling.

Sorry but you are implying that I would be inspecting what might be.

I am referring to what is as you discribe.

Your wiring design as discribe would be using a 12 circuit MLO panel as a main service rated panel and without 6 double pole breakers installed and being used in that panel places, as existing in your installation, more than the maximum 6 disconnect or sweep of the hand available in that main service rated panel. This discription would what is not what what might be.

To add the idea of a direct drive, nonfused, feed through set of lugs with no main breaker controling those feed trough lugs in that 12 circuit main service rated MLO panel makes this even more evident to be a violation of the maximum 6 disconnect rule.

I would like to hear other opinions on our discussion for further information along the line of this 12 circuit MLO feed through main service rated panel. I would like to see what other people feel about this subject allowing a variety of opions on the subject. Might be an interesting discussion.

Curious

Wg
 
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Old 06-11-02, 07:51 PM
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Inspection practices

You are inspecting what might be in saying that someone might put too many breakers in the panel. My contention is that if the panel is listed as service equipment, is installed with less than seven breakers in it, and it's service listing does not contain language requiring a main breaker that you are wrong to turn it down for a potential future abuse. All of the examples I gave were intended to illustrate how equipment can be misused after inspection. If you turn down the twelve slot service listed MLO because someone might place the wrong breakers in it then why not turn down a sectional switch gear assembly that has six breakers if it is possible to add a section and install additional breakers after inspection. What if the extra section is already there with two of its bays in use to hold the ground fault detectors and the conduit entries for the transfer switch feeder. If I have even one unused bay in that switch gear could I not install a seventh breaker assembly.

The moment you explained to the court that you turned the installation down to prevent a future act the plaintiff would be granted summary judgment. No competent court will allow anyone exercising the police power of the state to assume a future unlawful act.
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  #19  
Old 06-11-02, 08:22 PM
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We have both spoke our interpretations. I am curious what other people believe on this subject.

Curious

Wg
 
  #20  
Old 06-12-02, 08:21 AM
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OK, I went through and performed the load calculation and I came up with 192 Amps. I don't think I missed anything. Sound about right? Any concerns?

I'm curious though- Doesn't this calculation assume you have practically everything in the house turned on and/or running all at once?
 
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Old 06-12-02, 02:14 PM
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If you performed the demand load calc as formatted in the link I provided you should have noticed that you were allowed a credit to reduce load in many areas such as 100% of the first 3000 volt amps of the general load but the remaining general load was allowed a reduction of 65%. Then when you counted your heat versus a/c you only counted the largest of the two loads dropping the other smaller load concerning heating and cooling. Then when you calculated the fastened in place appliances you were allowed a 25% reduction of load on any fastened in place in excess of 4 appliances. Then when you calculated your electric range you calculated 7 kw even though your range may be 12 kw rated. These reduction in loads are called diversification of load accounting for intermittent loads not all being on at the same time.

Sounds like whoever installed all the branch circuits serving that dwelling split the branch circuits to rather small load using numerous branch circuit above the minimum safety standards. This is fine I always love to see more safety designed into a home's wiring system than minimum safety standards.

Good Luck

Wg

Hope this helps

Wg
 
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Old 06-13-02, 07:40 AM
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These reduction in loads are called diversification of load accounting for intermittent loads not all being on at the same time.

OK, so the reduction factor IS the assumption that you don't have every light on while running every single thing in the house at once. -Gotcha.

Thanks for the link and for the tips. I'm sure I'll have more questions to come as this project continues. Now, I've got all the wiring done in the garage so they all come together at a single point where it'll go into the existing house. I'm working on wiring the bonus room up now, running all the wires for it to the same spot.
 
  #23  
Old 06-13-02, 03:12 PM
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Where do you get 192 amps on a 1125 sq.ft.?
 
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Old 06-13-02, 05:10 PM
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Jxofaltrds, this is a long post with several off shoots of conversations but way up in this post KevinA said;

There's a box outside next to the meter that is a 200 amp box w/ circuits for the HVAC, water heater, hot tub, range, etc, and one for the inside panel. It has 12 slots, all full (6- 240v circuits). Inside there is a 150 amp box with 20 slots in it- all full, except the 2 available from the deletion of the 240 baseboard heater.



Counting a 5.5 horse power 120 volt air compressor at the end and then what ever else he has in that house.

Add loosely 60 amp for the heat pump or a/c and gas furnace combined. then add 30 for the water heater then add 40 for the range then add 50 for the hot tub then add 60 for the air compressor and you would total with a 25% reduction of about 180 amps then add your general lighting loads to that not counting what else he has that I am not aware of and you are up there in amps concerning a demand load calc. I suspect he is close in his calculations.

Sounds like he as a lot of amps packed in a small square foot package to me but believe he is close in his demand calc as I pick up his fastened in place loads.

Surprising isn't it?

Wg
 
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Old 06-13-02, 07:04 PM
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Where do you get 192 amps on a 1125 sq.ft.?
Ummm, sounds like you guys are forgetting this is an addition we're talking about here. The 1125 sq ft was added on to an existing 1560 sq ft house for a total of 2685 sq ft. The load calc was based on the new total square footage.
 
  #26  
Old 06-13-02, 09:00 PM
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Kevin A We haven't forgot it was an addition. The service size is of the whole house the major load is the original kitchen, heating and cooling, motor loads such as air compressors and fastened in place appliances.

While you addition will add to the load the load would be minor except for machines being installed such as your air compressor.

You spoke that your original square footage was 1560 square feet. The general lighting load not counting your existing laundry or kitchen loads would only would be 3 volt amps per square feet totaling without and diversity for intermittent usage 19.5 amps for general lighting considering square footage load only.

YOu addition you said was 1125 square feet totaling general lighting load only again with no existing included and no machineray 14.6 amps.

General lighting only with the addition and the existing square footage would be 34.1 amps. The big loads that rack up fast were what we were talking about trying to show Jxofaltrds why your demand load calculation was showing so high with such a small home that he was quoting. The square footage was not your major concern as much as all the resistance heat and motors you have in your home. They punched your demand load up pretty high. You said you followed the demand load calculaton at the link I provided. Are you unsure you calculated the demand load correctly?

Wg
 
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Old 06-14-02, 05:40 AM
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Are you unsure you calculated the demand load correctly?
Yea, I think so. Finishing up engineering degree- ie: lots of experience in calculating stuff :-)

I understand, too, that square footage by itself doesn't add much load. Sure, every house has the same basics- stove, w/d, hvac, etc. That stuff is where the load is.
 
  #28  
Old 06-14-02, 01:46 PM
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Having reread the post it sounds like the whole house load is 192 amps. I thought you were saying the addition was 192amps. Just install a 100 amp sub, do not fill it, however wire for it. You can install a 50 amp breaker to protect it. If you do further additions and have to replace the main at least you are ready.
 
  #29  
Old 06-19-02, 08:29 AM
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Originally posted by Wgoodrich
We have both spoke our interpretations. I am curious what other people believe on this subject.

Curious

Wg
How about checking out the illustration in the NEC handbook in the commentary following 230.90 (A) exception 3. This clearly illustrates the very installation I was talking about with the only difference being the panel is for a three phase service.
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Old 06-19-02, 10:19 PM
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Tom

We are not talking about an industrial building. We are talking about a dwelling where do it yourselfers are going to do 90 % of the work. Do you really believe that homeowner is going to know that he has overloaded his service entrance conductors by performing a demand load calculation? Many electrician don't know how to do a demand load calculation. To install a main lug only main service rated panel is to invite a melt down of that service entrance conductor when the home owner starts playing tool time. Do you want that on your mind the risk that someone can burn their house down or worse becuase you didn't want to install a main breaker in the panel?

Try reading the following rule and commentary that may help

230.23 Size and Rating.
(A) General. Conductors shall have sufficient ampacity to carry the current for the load as computed in accordance with Article 220 and shall have adequate mechanical strength.

HANDBOOK COMMENTARY;
When a load is added to any service, the installer must be aware of all existing loads. The potential for overloading the service conductors must be governed by installer responsibility and inspector awareness; they should not rely solely on the usual method of overcurrent protection. The serving electric utility should be alerted to whenever load is added to ensure that adequate power is available.


MY PERSONAL THOUGHTS;

50 % or more of work done in a home the inspector or original electrician will never know.

Is saving the minor dollars deleting a main breaker in a service panel worth that risk?

As an inspector I am fully aware and have seen the heartache in people not knowing they don't know. I can not in clear conceience allow such an invite to a disaster to happen when a home owner does not want to call an inspector and does not know he or she just struck a match to cause a service entrance coductor to have a melt down when the changed from gas heat to electric heat. They had the open slots to place those new breakers why not use them.

To me I have the authority to require the 12 slots to be used or a main installed due to the above rules mentioned in this discussion. I just couldn't allow such an invite to disaster.

To confirm what I am talking about read the following posted subject active today on this forum;

http://forum.doityourself.com/showth...303#post287303

Wg
 

Last edited by Wgoodrich; 06-19-02 at 10:39 PM.
  #31  
Old 06-20-02, 07:05 AM
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Originally posted by Wgoodrich
Tom
SNIP
To me I have the authority to require the 12 slots to be used or a main installed due to the above rules mentioned in this discussion. I just couldn't allow such an invite to disaster.
SNIP
http://forum.doityourself.com/showth...303#post287303

Wg
wG
Here is the heart of the issue. If you as a public official enforce your view of best practice rather than the electrical code as written you are exceeding your legal authority and abusing the public trust. A Public electrical inspectors job is to enforce the electrical code that has been adopted as law in her/his jurisdiction. Our whole system of law is based on having a government of laws rather than a government of men. When you substitute your personal opinion of what is right for the law you are bound in duty to enforce you are no longer functioning as a public official. By picking and choosing the sections of the code that you will allow citizens to apply you set your self up as superior to the elected officials and the elected legislative body that adopted that code by reference. You are not the first inspector to do so and you won't be the last but that does not make it right.
By setting up bureaucracies that are totally inaccessible to ordinary citizens we force them to do work on the sly because we deny them access to a system of qualified electrical inspectors that are paid for with their taxes. That is the real weakness of the present system rather than the inadequacies you believe are in the code as adopted into public law.
--
Tom
 
  #32  
Old 06-20-02, 12:04 PM
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Tom

I agree with what you said in your last post. However even a public official has a code of ethics that person must maintain within himself. In this discussion it is obvious that I would not sign an approval of a set up as you discribe. I believe it is unsafe and against Code. However I have yet to have found a piece in the Code that says you can't do as your discribe by installing a main lug only panel as a wild card in a dwelling. I will keep looking and let you know what I find if I find anything.

As a public official in my jurisdiction if we were doing this discussion on a professional matter with me using my AHJ powers I would have a long time ago told you of your right to appeal my ruling and tell you how to do that appeal. Then I would have guaranteed that you would experience no reprisal no matter the outcome of that appeal in future inspections. At the appeals board hearing that board may over ride my ruling citing that I used a personal opinion not compliant to the Code. I would state my case you would state your case and we both would live with that ruling unless you sought further appeals through the judicial system in a civil case. I still would not be mad at you as I am not now. However if you won the appeal someone else's name would be on that hazardous wiring design. My personal ethics would not allow me as a public official to rule against my own common sense. If the appeals board wanted to accept that responsibility of accepting your design I would not have a negative feeling on the subject. They would put their name on it ruling that I must put my name on it. I would then do as the appeals board ruled. Then we would go have coffee together and talk about the sunshine. Pesonal is personal and business is business.

The above discription is what is available by law as an appeals process. The difference of opinions such as what we have in this subject is exactly why there are supposed to be avenues of appeals. It is called the American way.

AS for ever hoping that public officials will be machines without personal ethics is a pipe dream. This fact is why avenues of appeal should not only be available but should be utilized.

As a public official I am not requiered to violate my own personal ethics. However I am required to inform you of your right of appeal and not only would do that I have done that more than once in my jurisdiction when an electrician and myself can not come to agreement as to interpretation. The appeals process in my jurisdiction is normally resolved within one weak with the ruling issued. Can't ask for better than that.

After discussing different subjects with you I have no doubt you woiuld use the appeals process. IF you paid close attention to my reactions to those who disagree you should have noticed by now I do not take things personal as many AHJs do. IF you worked in my jurisdiction I would have told you at the beginning of our working relationship that I will not be a dictator in the field but I will stand to my beliefs until proven wrong. If you work hard enough I can be proven wrong. If you convince me and I think by now you know that is not easy. I will admit being wrong. I would also tell you at the beginning of our working together that the only time that you could make me mad at you is if you don't speak up when you think I am wrong. Again I don't think you have that problem speaking your stance.

No inspector should be a dictator. But an break in discussion should never happen until there is no other choice.

The last rule you provided may have swayed me but I am still reseraching before I admit who is right on this subject. Blieve me when I say that if I can not prove your stance wrong in my mind there will be a code change request issued to the NEC for a change in that rule making dwellings not allowed as you are discribing. Way too much hazard invited in that design. I have readliy approved what you discribe in industrial settings but your wiring design does not belong in a dwelling where we lose control of what happens inside without those people being skilled enough to know they are setting up a fire or death trap.

Wg
 
  #33  
Old 06-20-02, 01:32 PM
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Appeals and code change proposals.

As long as you took that stance I could not quarrel with it. Given what I have seen in the old split buss panels I can understand you wanting a code change. I believe that the CMP already took care of that problem when they required that lighting and appliance panel boards have only one or two disconnecting means. Since these multi breaker service disconnects now only make sense when installed remote from the lighting and appliance panel board I do not think that there is a lot of temptation to mess with them at all. They are usually on the outside of the home and thus not terribly convenient to run 120 volt branch circuits to. The reason That I use them is that they permit independent control of the power to the water pump and separate buildings. I mount them on a free standing board on posts and I keep them several feet from the closest building. If a problem develops in any building you can disconnect the problem without killing power to the other buildings or the water pump. A fire that takes down the feeder to one building will not necessarily kill all power as is likely to happen with a single main breaker service.
 
  #34  
Old 06-21-02, 04:05 PM
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Hornetd, try the following copied section in my attempt to hit a rule against leaving 8 or 10 open circuits in a service rated MLO panel without a main breaker. Notice that the limit of percent of circuits that can take 30 amps or less must be less than 10%. I read this to say that if you have two open circuits in a 12 circuit MLO service rated panel unused then you could use the MLO panel without a main breaker. But if you can install more than two breakers in that power panel you would be required a main breaker on the load side of that MLO panel.

(B) Power Panelboard Protection. In addition to the requirements of 408.13, a power panelboard with supply conductors that include a neutral and having more than 10 percent of its overcurrent devices protecting branch circuits rated 30 amperes or less shall be protected by an overcurrent protective device having a rating not greater than that of the panelboard. The overcurrent protective device shall be located within or at any point on the supply side of the panelboard.
When a power panelboard is required to have overcurrent protection, such protection can be provided by an overcurrent device in the panelboard or by an overcurrent device protecting the conductors that supply the panelboard. In either case, the rating of the overcurrent device is not permitted to exceed the rating of the panelboard. For example, a feeder protected by a 450-ampere overcurrent device supplies a panelboard with a 600-ampere rating. Because the panelboard is obviously large enough to supply the calculated load and the overcurrent device protecting the feeder does not exceed the rating of the panelboard, an individual overcurrent device in the panelboard is not required. Note that where the panelboard is used as service equipment, the exception to 408.16(B) allows the panelboard overcurrent protection to be multiple devices in accordance with the “six-disconnect rule” in 230.71.
Exception: This individual protection shall not be required for a power panelboard used as service equipment with multiple disconnecting means in accordance with 230.71.


Then look at 230.71 calling for a maximum of 6 sweeps of the hand. YOu have available 8 sweeps of the hand if you only have two double pole breakers in that panel and 8 more open for either double or single pole breakers. What is would be a power panel with more than 10% available in that power panel as 30 amp or smaller breakers and more.

If you had installed an 8 circuit MLO panel with two double pole breakers in it then you would physically be limited to 6 sweeps of the hand. That I would not have challenged.

Read the following Rule that applies to lighting and appliance panelboards;

408.16 Overcurrent Protection.
(A) Lighting and Appliance Branch-Circuit Panelboard Individually Protected. Each lighting and appliance branch-circuit panelboard shall be individually protected on the supply side by not more than two main circuit breakers or two sets of fuses having a combined rating not greater than that of the panelboard.


Read the following about split phase power panels in the handbook commentary;

Handbook Commentary 2002 NEC;
The phrase “for existing installations” in Exception No. 2 refers to the existing panelboard. It is not intended that a split-bus panelboard used in an individual residential occupancy be replaced if a circuit is added to the existing panelboard. It does mean, however, that for the installation of new panelboards in new or existing residential occupancies, a split-bus six-disconnect panelboard (with more than two circuit breakers or sets of fuses protecting the panelboard) is not permitted for the service equipment.
An individual residential occupancy could be a dwelling unit in a multifamily dwelling where the panelboard is used as service equipment. See the definition of dwelling unit in Article 100.

Have I found enough intent in the NEC against leaving 10 open circuits in a Main Lug Only service rated panel?

Curious

Wg
 
  #35  
Old 06-22-02, 10:18 PM
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No common ground

WG
If you continue to believe that you have a right to inspect what might be instead of what is at the time of inspection then we have no common ground from which to begin.
I never suggested installing any form of split buss panel. I only mentioned them to illustrate that I understood your concern about future abuse.
The code clearly states that the installation I suggested is compliant. The listing of the panel clearly states that it is "suitable for use as service equipment when not more than six main disconnecting means are installed and not used as a lighting and appliance panel board." Both are quite eloquent in what they do not say. Neither the UL white book or the NEC says anything about the installation being immune or even resistant to future tampering. CTL panel boards are easily overloaded by using breakers marked for replacement use only. There is nothing you or indeed anyone else can do to prevent human stupidity.
The difference between our two positions is that you think an inspector can apply standards other than the code as legally adopted. That is an idea that I reject. I believe it is an abuse of the police power of the state which you are bound in duty to apply only as the law allows. Your appointment as an electrical inspector does not make you master of anything electric in your jurisdiction.
You said yourself we are a nation of risk takers. If this were sweden or some other socialist country your approach would be normal government policy but in a free society your approach is not only excessive it is unlawful.
--
Tom
 
  #36  
Old 06-23-02, 09:16 PM
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In my eyes after experienceing this post it is my beleif that you tend to portray a dislike for people of authority, specifically inspectors.

Bottom line is you have a 12 circuit panel with many breakers spaces still available without any plan to use them or limit their use. This does not meet the intent of a power panel but does meet a lighting and appliance panel board. Therefor in my eyes I am concerned about what is, not as you say, I want it to be or what may be in the future. What is as you discribe is a panel board MLO that has well over the 10% open circuits available that you have not filled using your six disconnect rule. Either utilize the space or install a smaller number of branch circuits in that panel meeting the 10% max beyond the main breakers of a power panel board.

Sorry, you have a distaste for my way of thinking but I have a distaste for people bending the rules to make look like they are meeting the NEC rules. Safety is the goal and the intent is not met by your discription leaving that many open spaces for double pole or single pole lighting and appliance branch circuit usage. YOu have no valid reason to install such a large MLO panel and want to use no main breaker other than playing games with the rules of the NEC. If you limit the number of circuits available to what you need and possible a pair of spare circutis for futrure you would limit the concrens for safety many people would have. I suggest that you reread this post and take a real close look as to who was abrasive and who was trying to help. I have been in this post to help. You have been in the post throwing jabs at inspectors all the way through the post. For that pattern of friction protrayed by you, I am disappointed.

Have a good day

Wg
 
  #37  
Old 06-29-02, 08:48 AM
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Legitimate role of inspectors

Originally posted by Wgoodrich
In my eyes after experienceing this post it is my beleif that you tend to portray a dislike for people of authority, specifically inspectors.

Bottom line is you have a 12 circuit panel with many breakers spaces still available without any plan to use them or limit their use. This does not meet the intent of a power panel but does meet a lighting and appliance panel board. Therefor in my eyes I am concerned about what is, not as you say, I want it to be or what may be in the future. What is as you discribe is a panel board MLO that has well over the 10% open circuits available that you have not filled using your six disconnect rule. Either utilize the space or install a smaller number of branch circuits in that panel meeting the 10% max beyond the main breakers of a power panel board.

Sorry, you have a distaste for my way of thinking but I have a distaste for people bending the rules to make look like they are meeting the NEC rules. Safety is the goal and the intent is not met by your discription leaving that many open spaces for double pole or single pole lighting and appliance branch circuit usage. YOu have no valid reason to install such a large MLO panel and want to use no main breaker other than playing games with the rules of the NEC. If you limit the number of circuits available to what you need and possible a pair of spare circutis for futrure you would limit the concrens for safety many people would have. I suggest that you reread this post and take a real close look as to who was abrasive and who was trying to help. I have been in this post to help. You have been in the post throwing jabs at inspectors all the way through the post. For that pattern of friction protrayed by you, I am disappointed.

Have a good day

Wg
The only dislike I have for authority is for people who abuse the public trust by taking a fiduciary position and then acting like little tin pot gods. The electric code has to be enforced in a manner consistent with the basic principals of american law. One of those principals is that no one exercising the police powers of the State is permitted to presume the commission of future unlawful acts. You must look at what is there rather than what you believe may be there some day. Nothing that you have quoted supports your position that you can reject an installation because you believe it may someday be abused. No competent court would allow any ruling that is based on the presumption of a future act to stand. You appear to have confused your appointment as an electrical inspector with being anointed as some sort of infallible authority on what constitutes good practice in the industry. Your position is entirely unsupported by the precedents and accepted practices of administrative law in the United States.

I have checked with the local inspectors and with the NFPA's electrical engineering section. Both resources have said your position is not supported by the US NEC. The local inspectors based their answers on the 1996 edition. The NFPA based theirs on the 2001 edition.

You have stated repeatedly that a twelve slot MLO panel is a lighting and appliance panel board but all the answers to the same question on several other NEC discussion boards have said that the installation is permissible if not more than six main disconnects are installed and none of them supply circuits that contain a neutral connection from breakers rated thirty amperes or less.

You say I am being abrasive and that you are trying to be helpful. I do not see standing up for what I believe to be right as abrasive. I do not see giving advice about what the code requires based on only your say so and out of step with the rest of the industry as helpful. It would appear to me that you are unwilling to admit the possibility that you are wrong. I have checked with several other NEC bulletin boards, local AHJs and the NFPA engineering office and was at every point prepared to find out I was misinterpreting the NEC. No such outcome having been forthcoming I have concluded that my original advice was sound. It would appear that you are determined to be the only big fish in this pond and that you are comfortable never looking beyond it. The unfortunate thing about your approach is that you will cause people to undertake work at greater cost and less utility and even safety then the NEC allows.
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Tom
 
  #38  
Old 06-29-02, 12:15 PM
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Tom, everyone has a right to an opinion. To hash this over any more would be without merit. The differing of you interpretation and my interpretation is never going to see positive outcome of this discussion. This is why they have a judicial branch and appeals hearings to have a third party hold a legal hearing and make a ruling. Even if that was done between the two of us neither party would change their belief. I don't judge you and appreciate it if you don't judge me. I have never proposed to own this site. I do spend a lot of time trying to help people with their questions and provide the Code info when I can. If you read a reply issued by me and you disagree with that reply then please feel free to post your opinion and provide the Code reference number you are coming from on your opinion. I have no problem with being corrected nor does anyone else that I know of in this forum. When there is a difference of thought usually someone can learn from that discussion. Sometimes that person is me that learns sometimes that person who learns something new is someone else. We are not on an ego trip in this forum. This is why it is so popular. People are free to say what they believe and people are free to disagree. Just provide the Code reference number to substantiate you belief. You may have others disagree with you stance. Sometimes the are reminded of something they already know. Ego and abrasive is not necessary nor desired by myself or anyone else in this forum. To issue a different opinion is always invited as long as it is in a constructive manner in an attempt to help.

In my eyes this post should be locked and end as a non postive progress to this post.

I will issue no more repies to this post. Seems to the best action is to agree not to agree.

Good luck

Wg
 

Last edited by Wgoodrich; 06-29-02 at 12:33 PM.
  #39  
Old 06-29-02, 08:52 PM
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Agreeing to disagree.

As long as that is what happens I am easy with that approach. I think we could have done that a while back by acknowledging that honorable people can disagree without attributing nefarious motives to some one who disagrees with you. So enough said and there's an end to it.
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Tom
 
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