Question about Dwelling service???

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threephase

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My house has a GE Load Center with 4 breakers, all feeding subpanels. I'm assuming this is within code even though there isn't a MAIN breaker considering it's within the 6 disconnect rule??

If there is a ground fault, short circuit downstream of the 4 breakers, that particular breaker will trip.

My question is, if the main feeder short to ground, what trips? POCO?

Lastly, they bonded the nuetral and ground both in the meter enclosure and in the GE main load center which is 8 inches away. Is that right? I thought they were only to be connected at ONE point?

Threephase
 
threephase said:
My question is, if the main feeder short to ground, what trips? POCO?
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the same thing that trips as if you had a main. The main in a panelboard protects only the bus structure inside the panelboard from short circuits.
 
threephase said:
My question is, if the main feeder short to ground, what trips?

Lastly, they bonded the nuetral and ground both in the meter enclosure and in the GE main load center which is 8 inches away. Is that right? I thought they were only to be connected at ONE point?
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What trips is maybe an overcurrent device at the transformer, and if not that then your service or service lateral will melt. Usually, you wires are bigger than the POCO's wires, so it will be their job to fix it.

On the line side of the service, all equipment is bonded to the neutral (meter can, CT boxes, your main disconnect, etc). It is only at the service disconnect where the downstream neutral/ground separation must begin.
 
Sounds like it meets code.Not saying i like the setup but if the 4 breakers total to amps of the service its probably safe.Personally i prefer to have just one main breaker.
 
iwire said:
FWIW the breakers combined rating can greatly exceed the conductors rating.
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Yes ,and when they do the problems begin.The original calks might been fine.Whats been added thru the years ?If they are all 100 amps you could hit a peak load of 400 and start a fire.
 
stickboy1375 said:
Your Logic is a bit out there Jim... We don't even know what the service is rated at...
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I just look at what could happen.While unlikely the posability is there.People add things like hot tubs,pools,garage workshops.
 
Jim W in Tampa said:
I just look at what could happen.While unlikely the possibility is there.People add things like hot tubs,pools,garage workshops.
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Not really disagreeing with you, just pointing out that the code allows the service conductors to be based on the calculated load not the breaker size.

Here is a fairly typical service in this area.

Dennis8.jpg



600 amps worth of breakers inside, does that riser look like it has 600 amps of service conductors?
 
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stickboy1375 said:
Your Logic is a bit out there Jim... So if I install Four 50amp breakers in a 200amp service are you worried?
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What if you install four 100 amp breakers as the service disconnect on this 200 amp riser.

It is perfectly NEC acceptable.
 
Jim W in Tampa said:
I just look at what could happen.While unlikely the posability is there.People add things like hot tubs,pools,garage workshops.
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Sad to say, but isn't that the electricians job to evaluate the existing service before moving on to big electrical additions?
 
stickboy1375 said:
Sad to say, but isn't that the electricians job to evaluate the existing service before moving on to big electrical additions?
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Yes. :cool:

Do you generally do a full set of calcs when you add a hot tub?
 
iwire said:
Yes. :cool:

Do you generally do a full set of calcs when you add a hot tub?
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If it's already a 200 amp service I will look at the panel (check for electric heat, etc....) and the size of the house, but if it is a 100 amp, yes, I will recalculate the new service... mostly happens with 100 amp services and the HO wants to add central air...
 
iwire said:
Not really disagreeing with you, just pointing out that the code allows the service conductors to be based on the calculated load not the breaker size.

Here is a fairly typical service in this area.

Dennis8.jpg



600 amps worth of breakers inside, does that riser look like it has 600 amps of service conductors?
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I do think in this case it is unlikely all 6 units are maxed out at any given time.Also being its an apartment the chances of big extras being added are low.
As to the OP,i would do an updated load calc and then do what i felt is safe.Likely its still ok.
 
Just to answer you last question. Typically the neutral conductor would be use to bond the meter can and would not require a EGC. Is the raceway between the meter and service disconnect metallic if so they may have installed bonding bushings but should have only bonded one end most commonly the service disconnect side.
 
Bea,
Is the raceway between the meter and service disconnect metallic if so they may have installed bonding bushings but should have only bonded one end most commonly the service disconnect side.
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The code only requires one end to be bonded, but does not prohibit the bonding of both ends. Some utilities, like the one in my area, require both ends to have bonding bushings if the service raceway is metallic.
Don
 
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