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Re: Recommended solar panel brand

Paul Dowd and Sharon Brown
 

Scott,

 

The problem I have is that I use a VSAT which has three thick cables taking up most of the conduit space. I am told that by putting schottky diodes between the panels the loss due to uneven shading across panels is significantly mitigated, although I have not tried it yet, and indeed would be interested to hear from anyone who has. Having said all that, we are extremely pleased with the performance of these panels, and now find that we only need to run either the engine or generator to get hot water! We have 4 year old AGMs.

 

Cheers,

Paul

S/Y Ya Fohi - Amel 54 #98

 

From: main@AmelYachtOwners.groups.io <main@AmelYachtOwners.groups.io> On Behalf Of Scott SV Tengah
Sent: 18 February 2020 12:24
To: main@AmelYachtOwners.groups.io
Subject: Re: [AmelYachtOwners] Recommended solar panel brand

 

Paul:

Exactly right. I saw a test where they wired multiple panels parallel and serial and saw that partial shading from booms/sails really dropped output on serially connected panels. I was able to obtain the same results when performing the same experiment.

Where do you have your MPPT? I have all six wires running from the arch to two switches (pos/neg) in the starboard side of the lazarette. With the short run and only one panel per pair for this section, I don't need super thick cables. Then I run a single pair of 13mm2 wires to the MPPT located near the boat's main switches. That fit in the conduit with room to spare and I believe the calcs showed very acceptable voltage drop even at the max 960watt output.

There is some argument that the higher voltage with serial will turn on the mppt earlier since it requires (battery voltage+5v) to startup, but frankly, I am fine missing out on a few minutes of early morning sun. I'm also thinking that 35-40 volts on the parallel panels might be safer in the event of a catastrophic event. 120-130v DC could hurt.

--
Scott 
2007 A54 #69
SV Tengah
http://www.svtengah.com


--
Cheers
Paul
Ya Fohi - Amel 54 #98
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