Re: [RE-wrenches] Low array voltage stumper on legacy system

2016-08-25 Thread Jay
Hi Allan, I would try turning off string #3 and see what happens to the vmp. I'm guessing it'll go up to a more normal voltage. I just had a very similar experience, also BP modules, very brown. 2 sets of 4 billion n series to a 12v system. One set was totally dragging down the VMP, I

Re: [RE-wrenches] Low array voltage stumper on legacy system

2016-08-25 Thread Jerry Shafer
Brian Can you do a solmetric type test, when you performed the amp test the volts were at near "0" so the test does not show an accurate value, you said the modules are brown this is not good but are they checked because if so you are done needs new modules. I would suggest doing some additional

Re: [RE-wrenches] Low array voltage stumper on legacy system

2016-08-25 Thread Brian Mehalic
If it is a module issue it could be bad solder joints, shorted diodes, or a combination of both. I just curve traced 12 12-year old KC120s - all except 2 tested fine for Voc with a DMM (2 were totally dead). However with the curve tracer they all exhibited more of an IV "angle" than a curve,

Re: [RE-wrenches] Battery issue

2016-08-25 Thread Drake
I only supply L-16s at my cost to clients with existing banks than have failures. It has been hazy of course as to what is due to poor maintenance and what is due to defective batteries. There was a Trojan Rep on the list. If you are still here, please chime in. At 10:56 AM 8/24/2016, you

Re: [RE-wrenches] Low array voltage stumper on legacy system

2016-08-25 Thread Steve Bell
Hello Allan, Did you check the Voc of each string? Is it possible that there could one or more shorted bypass diodes in the modules? Just a thought. Steve Bell Morningstar tech support On Thu, Aug 25, 2016 at 8:04 AM, Allan Sindelar wrote: > Wrenches, > Here's one I

[RE-wrenches] Low array voltage stumper on legacy system

2016-08-25 Thread Allan Sindelar
Wrenches, Here's one I haven't seen before. 1997 grid-tie battery backup system that was one of my first, although actual installation was by another before I was licensed. 16 BP 275, 36-cell 12V modules, the standard of that time. Early Outback MX60 replaced C40 around 2005; array rewired to