CA Traveler wrote:
StirCrazy wrote:
I have seen several tests and such on the benifits of serial over paralell. there actualy will be a difference in morning votage between the two even if using 24V panels. my controler can take 140V in so that would let me stack three 24V panels and still be save. 4 and I am asking for trouble. but lets say I have three and early morning they are putting out 6V each, that adds up to 18V which is over the threshhole to start charging. if I had three paralell then it would only be 6V and wouldn't get a charge untill the sun came up more. not sure if thats what you were getting at but thats how I read it so I apoligize if I misunderstood what you were trying to say.
Steve
My apologizes as I've seen that also. I should have stated that the irridation is very low including amps in the early morning and hence the power output is small but it does contribute.
I've never seen 6V on a 30V panel. It has to happen of course since it's 0V at night. I've seen 90V (3 panels) at very low amps in the early morning light and no sun.
I've seen charging at 20V and 30V for 2 and 3 of the 9 panel sections w/o sun due to a tree and the bypass diodes activated for the other sections. I might have a graph of that event.
you won't see the 6V unless you are directly measuing the panel output with a seperat meter. most of the controlers have a threshold voltage where they do nothing till that min voltage is met. so 6V everything sits dead, but 18V it starts charging as the threshold is met. I played with my panel before i installed it to see what the max open circut voltage was and then I just wanted to see ifmy led lights in the garage would make it work haha
