[RE-wrenches] Disconnect BOTH positive and negative conductors from array?!?

[Drake]

This is from the 2008 NEC


690.13 All Conductors.
Means shall be provided to disconnect all current-carrying conductors 
of a photovoltaic power source from all other conductors in a 
building or other structure. A switch, circuit breaker, or other 
device, either ac or dc, shall not be installed in a grounded 
conductor if operation of that switch, circuit breaker, or other 
device leaves the marked, grounded conductor in an ungrounded and 
energized state.
Exception:  A switch or circuit breaker that is part of a 
ground-fault detection system required by 690.5 shall be permitted to 
open the grounded conductor when that switch or circuit breaker is 
automatically opened as a normal function of the device in responding 
to ground faults. The switch or circuit breaker shall indicate the 
presence of a ground fault.
FPN: The grounded conductor may have a bolted or terminal 
disconnecting means to allow maintenance or troubleshooting by 
qualified personnel.



At 04:51 AM 9/15/2012, you wrote:
>>Bob,
>
>The problem with switching both conductors (in a normally grounded 
>array) is that opening the disconnect removes the bond to ground. 
>This takes the ground fault protection and detection system out of 
>the scheme (which would at least have operated with the disconnect 
>open on the normally ungrounded conductor).
>
>An inspector should appreciate the value of maintaining the 
>functionality of the ground fault protection system. 690.13 makes 
>this clear, by allowing the grounded conductor to be disconnected by 
>service personnel.
>
>Isaac Opalinsky
>
>_______________________________________________
>List sponsored by Home Power magazine
>
>List Address: RE-wrenches at lists.re-wrenches.org
>
>Options & settings:
>http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
>
>List-Archive: 
>http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
>
>List rules & etiquette:
>www.re-wrenches.org/etiquette.htm
>
>Check out participant bios:
>www.members.re-wrenches.org