[RE-wrenches] Solar accumulation panel

[Hans Frederickson]

690.15, second paragraph supports Drake's method:

"A single disconnecting means in accordance with 690.17 shall be permitted
for the combined ac output of one or more inverters or ac modules in an
interactive system."

690.17 says the disconnecting means can be a switch or circuit breaker. This
seems workable, with a couple caveats... The inverter manufacturer
directions might specify an individual branch circuit, and you would need to
use the larger size wire between the AC combiner box to the fused AC
disconnect at each inverter, so you would need to choose disconnects with
big enough terminals.

Anyone see any other issues with this idea?

-Hans

________________________________

From: re-wrenches-bounces at lists.re-wrenches.org
[mailto:re-wrenches-bounces at lists.re-wrenches.org] On Behalf Of Drake
Chamberlin
Sent: Wednesday, January 13, 2010 9:59 AM
To: RE-wrenches
Subject: Re: [RE-wrenches] Solar accumulation panel


P.S.

In many cases it would be necessary to use a fused AC disconnect to stay
within the inverter manufacturer's specifications. 

At 12:53 PM 1/13/2010, you wrote:


	Here is a wild idea.  If you  look at the Enphase inverter systems,
several inverters connect together in parallel before going to an
overcurrent device.  
	
	In all cases, the point of connection to a utility system must be at
a dedicated breaker.  If there were multiple string inverters that would
connect to one breaker, why not just use a junction box, instead of a
combiner panel?  You could put in an AC disconnect for each inverter, if it
didn't come with one.  
	
	The wiring would need to be sized for the combined output of the
multiple inverters, which in many cases wouldn't be an issue.
	
	Drake 
	

Drake Chamberlin
Athens Electric
OH License 44810
CO License 3773
NABCEP TM  Certified PV Installer 
Office - 740-448-7328
Mobile - 740-856-9648