[RE-wrenches] Battery Fuse Locations

[William Korthof]

Also, I think working clearance requirements are relaxed. 

Very sensible. Battery packs present a potential for serious problems in the event of an uninterrupted fault. 

IMHO, in the US, we already have far too many complicated code rules on PV systems. But for battery systems, this exception is wise... and I think we should a step further and provide a mid-point protective fuse in the middle of each battery string. 

/wk


On Aug 10, 2014, at 11:03 AM, Richard.L.Ratico at valley.net (Richard L Ratico) wrote:

Drake,
It seems the code is providing some flexibility for the location of OCPD in
battery circuits. Placement "as close as practicable to the storage battery
terminals" is ok even if that is in an enclosed space (say a battery box) where
the possible accumulation of flammable gases may occur.

Dick Ratico
Solarwind Electric



--- You wrote:
Hello Wrenches,

I'm studying the NEC for a rectification exam, and came across this 
little gem. Can anyone explain what the following code rule is saying 
from 240.21 H, (Overcurrent Protection, Location in the circuit)?

(H) Battery Conductors. Overcurrent protection shall be
permitted to be installed as close as practicable to the storage
battery terminals in an unclassified location. Installation of the
overcurrent protection within a hazardous (classified) location
shall also be permitted.

It seems to say we can't do something, but we can anyway. The 
Handbook provides no clarification.

Thanks,

Drake
--- end of quote ---
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