Is oversized sub-panel permitted in the code?

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titan1021

titan1021

Senior Member
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Northern California
I am wondering if the code permits installing a oversized panel when more breaker spaces are needed. For example can a 200amp sub-panel be installed where a 125amp sub-panel was previously existing or 125amps is all that is available. This would be done to gain the additional breaker spaces for loads that are not continuous. I haven't been able to find a section in the code that pertains to this.

Any input is greatly appreciated !

Thanks
 
215.2 Minimum Rating and Size.
(A) Feeders Not More Than 600 Volts.
(1) General. Feeder conductors shall have an ampacity not less than required to supply the load as calculated in Parts III, IV, and V of Article 220. The minimum feeder-circuit conductor size, before the application of any adjustment or correction factors, shall have an allowable ampacity not less than the noncontinuous load plus 125 percent of the continuous load.

I have a 60 amp load with conductors and overcurrent protecting the feeders sized correctly.

I only have a 200 amp panel in the van so I install the 200 amp panel.
Does this panel change the calculated load, the size of the feeders or the overcurrent device protecting the feeders?

I guess the 200 amp panel would be okay then.
 
Certainly, NEC is about minimuns only. You can use 750 MCM on a 15-amp circuit if you want, can afford it, and figure out how to terminate it safely in a workmanship like manner...
 
Your 200 amp capacity rated panel would just become an oversized 125A protected panel. Its basically determined by the feeding (main) breaker. Of course you couldn't go the other way, but im sure you know that.
 
Earshavewalls......

Notice how the 2008 NEC revised some of that....

408.54 Maximum Number of Overcurrent Devices. A
panelboard shall be provided with physical means to prevent
the installation of more overcurrent devices than that number
for which the panelboard was designed, rated, and listed.
For the purposes of this section, a 2-pole circuit breaker
or fusible switch shall be considered two overcurrent devices;
a 3-pole circuit breaker or fusible switch shall be
considered three overcurrent devices. [ROP 9-127]

But is re-appears under

408.36 Overcurrent Protection.

Exception No. 2: Individual protection shall not be required
for a panelboard individually protected on its 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. A panelboard wired under this exception
shall not contain more than 42 overcurrent devices. For the
purposes of this exception, a 2-pole or a 3-pole circuit
breaker shall be considered as two or three overcurrent
devices, respectively.
Exception No. 3: For existing panelboards, individual
protection shall not be required for a panelboard used as
service equipment for an individual residential occupancy.

just some info .......ENJOY
 
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