Re: [RE-wrenches] Two strings of Different Orientation

2010-05-24 Thread Marv Dargatz
Subject: Re: [RE-wrenches] Two strings of Different Orientation   Bill, I agree with everything you're saying, if you substitute "cell temperature" for "ambient temperature". See ya!   Marv 707 763-4784  x7016 Bill Brooks wrote: Pe

Re: [RE-wrenches] Two strings of Different Orientation

2010-05-22 Thread Bill Brooks
ubject: Re: [RE-wrenches] Two strings of Different Orientation Bill, I agree with everything you're saying, if you substitute "cell temperature" for "ambient temperature". See ya! Marv 707 763-4784 x7016 Bill Brooks wrote: Peter, Not to belabor the issue, but

Re: [RE-wrenches] Two strings of Different Orientation

2010-05-21 Thread i2p
On May 21, 2010, at 9:47:59 AM, i2p wrote: From: i2p Subject:Re: [RE-wrenches] Two strings of Different Orientation Date: May 21, 2010 9:47:59 AM PDT To: RE-wrenches On May 20, 2010, at 7:11:45 PM, "Bill Brooks" wrote: Maybe it is a pipe dream, but I would like to

Re: [RE-wrenches] Two strings of Different Orientation

2010-05-21 Thread i2p
On May 20, 2010, at 7:11:45 PM, "Bill Brooks" wrote: Maybe it is a pipe dream, but I would like to think that designers, engineers, and knowledgeable installers will one day be able to accurately understand the irradiance and temperature impacts on I-V curves so that manufacturers will be

Re: [RE-wrenches] Two strings of Different Orientation

2010-05-21 Thread Marv Dargatz
Bill, I agree with everything you're saying, if you substitute "cell temperature" for "ambient temperature". See ya! Marv 707 763-4784 x7016 Bill Brooks wrote: Peter, Not to belabor the issue, but your understanding of the I-V curve and how it responds to changes in irradiance and t

Re: [RE-wrenches] Two strings of Different Orientation

2010-05-21 Thread R Ray Walters
I agree with your I-V curve interpretation Bill, I had never considered the counteracting influences on voltage of reduced irradiance and reduced temp. Very interesting. Also funny how most manufacturers quit publishing IV curves One way to check it Peter, is to turn each subarray on separa

Re: [RE-wrenches] Two strings of Different Orientation

2010-05-20 Thread Bill Brooks
Peter, Not to belabor the issue, but your understanding of the I-V curve and how it responds to changes in irradiance and temperature are flawed. I'm sorry you believe that I am misleading you, but the truth is that the I-V curve moves up and down with changing irradiance (current changes with irr

Re: [RE-wrenches] Two strings of Different Orientation

2010-05-20 Thread Peter Parrish
-Original Message- From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Bill Brooks Sent: Thursday, May 20, 2010 7:12 PM To: 'RE-wrenches' Subject: Re: [RE-wrenches] Two strings of Different Orientation Peter, Th

Re: [RE-wrenches] Two strings of Different Orientation

2010-05-20 Thread Bill Brooks
Peter, The issue is the same as it was last year. The operating voltage of each string will be nearly identical throughout the day if the strings are the same length and not shaded. Put them on a single inverter. The Fronius report was not discussing a special algorithm for dealing with this situ

Re: [RE-wrenches] Two strings of Different Orientation

2010-05-20 Thread Glenn Burt
How about a nice Power-One Aurora inverter with two MPP string inputs? http://www.power-one.com/renewable-energy/grid-tie-solar-inverters.php -Glenn Burt -Original Message- From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Pet