[RE-wrenches] Long MC Cable Mid String

[Drake Chamberlin]

I have scratched my head on this one before, because it seems that 
two terminals bonded together by a wire are essentially the same 
terminal.  The theoretical voltage difference on a terminal is 
zero.  How do we figure a voltage drop on a wire that has near zero 
volt potential between the ends of the wire.  Can we really use the 
voltage of the entire array to figure the drop on an interconnect 
between two modules?   If so, why can we do this?

Thanks,

Drake



At 07:49 PM 4/21/2009, you wrote:
>David,
>There will be less than a 1 volt drop in 36 feet of 10 AWG at the 11 
>amps you get from the Evergreen modules.  I don't think anyone will notice.
>David
>
>David Katz
>
>
>David Palumbo wrote:
>>Does the following series string wiring cause a problem? With  (18) 
>>Evergreen ES-A 205's (low voltage modules 18.4Vmp) in series 
>>feeding a grid tie inverter with a long series connector in the 
>>middle of the string.  (2) Top Of Pole 9 module mounts with the 
>>series connection from module #8 on the first pole to module #9 on 
>>the second pole. This MC cable connection would be, about, 36 feet 
>>in length to go 10' down the pole below grade 18" for 13' and back 
>>up the second pole 10' (in conduit all the way) .
>>
>>Will this extra long series wire cause problems?
>>
>>I could use other modules of course but that would raise the cost 
>>per watt by 70 cents.
>>
>>Dave
>>
>>David Palumbo, President
>>Independent Power LLC
>>462 Solar Way Drive
>>Hyde Park, VT 05655
>>NABCEP Certified
>><http://www.independentpowerllc.com>www.independentpowerllc.com
>>
>>
>>
>>
>>
>>
>>
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Drake Chamberlin
Athens Electric
OH License 44810
CO License 3773
740-448-7328
740-856-9648  
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