Then it should be PLENTY , if you are genuinely struggling to run a TV and LEDs off that bank , I would be worried something is wrong
Portable Power Grid - Whole House System
- Thread starter Jhp230gr45
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Jhp230gr45
New Member
You are correct... They are in parallel... I was told that unless you have constant sun it is not good to wire in series... Any thoughts on that?
The charge controller is an AIMS MPPT60 which works but the instruction manual is vague and tech support is clueless...
My panels are AIMS 250w @ 8.3amps per panel i believe...
Jhp230gr45
New Member
I haven't done it on a regular basis... I have disconnected it as a test to see if batteries drop significantly but isolated to themselves they dont seem to lose much more than 1/2 volt or slightly more... So i believe it could be a draw from controller...
MTM98290
Solar Enthusiast
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- Dec 24, 2022
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Maybe that is it. Could be that the controller is back feeding panels. I would measure to voltage on the panel wiring. If its not zero I would guess that a diode somewhere is just passing voltage both ways.
sunshine_eggo
Happy Breffast!
If the batteries have been fully charged the day before to 28.8V, then the voltage may settle as low as 25.2V first thing in the morning and still be fully charged.
Jhp230gr45
New Member
Parallel... The panels are 250w and i believe 8.3 amps each... (3 x250= 750)
Jhp230gr45
New Member
Thank you!... The batteries are enclosed in the trailer but are at the mercy of outside temps... Charging is affected by hot days.... Not so much in the cold..
sunshine_eggo
Happy Breffast!
Charging is affected by both. Lead acid requires temperature compensation - charging to higher voltages in cold and lower voltages in hot. Are you using it?
Are you dropping below 25.2V at the battery terminals overnight?
Amps isn't relevant, I need to know VOC, VMP voltages, also need to know max voltage the scc can have.
Parallel is more resistant to partial shading than series, but voltage needs to be high enough for the mppt to get charge current into the battery.
Hedges
I See Electromagnetic Fields!
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- Mar 28, 2020
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- 20,682
I think 27V is low, not a full charge. Look up what absorption voltage and for how long.
It also needs to be temperature compensated. At least set voltage manually for today's temperature, to test. Remove loads if required to maintain voltage and time.
Want a bigger array? Either a second set on top to flip out, or hanging on the side to flip up. Even both sides.
Jhp230gr45
New Member
It will hover around 24.6 - 25.0 overnight if you leave it alone and are not using any power... This is provided its had a good charging day...
Jhp230gr45
New Member
I guess Iwill have to do a measurement with my multimeter to get you an accurate output... Yes, i could be struggling because i am in the woods and some intermittent shading could be hurting me... I do need some trees cut to maximize sun time...
Info should be printed on back of panel.
I'm reading need 29.4V output to charge the FLA batteries...
Jhp230gr45
New Member
I have added another panel in the past but it didnt seem to help... Again it could be inconsistent sunlight... And we do get a lot of gray days here especially in the fall time...
The problem is low output voltage.
You need to put the panels in series.
Jhp230gr45
New Member
You are right... It does specify on the data tag... Hope this helps... Yes, I've always thought 29.0 should be the ideal standard as that would be an optimal 7.25 per battery...
Jhp230gr45
New Member
Will that be too much for my Mppt 60 controller?
I need to know the specs of the controller.
At minimum, you need to make them 2S
