Epever charge controller.

[Loveshack]

So what you are saying is that my solar is not powerful enough to reach 14.8v?
As well it won't be able to equalize at 15.6?

From memory I have checked my ac charger amperage at times and it is no where close to 70 amps when producing 14.4 v. I will check it again when I can to confirm.
I also understand that that is a false reading of 14.4 and when shut off it drops. I just thought the solar would give me the same false reading? It never shows 14.8v ?

I will ill check the specific gravity tonight after sun down and again in the morning and get back to you on thoughts figures.

My lap top connected to the mppt now 4pm is showing 100% soc

just checked the specific gravity and its about 1240 at 444pm
today we have had off and on rain and mixed sun and cloud. We are anchored
I will check it again in the morning.
I really appreciate your time and patients.
Thanks Dave

[Loveshack]

So I checked the specific gravity this morning. We used a fair amount to energy last night. (Tv on) This morning the batteries were at 1.225

[Loveshack]

Just as an experiment I shut off the solar and put on my 70amp ac charger. It is putting out about 55amps at 13.35 volts. When I force it into boost it was putting out 74 amps (70 amp charger ) and went up to 13.6, still not the 14.4 it is programmed for. All of your help is paying off. I am on the learning curve. I guess an upgrade in my solar size will be in the future. For now I would think that for my batteries putting on the generator in the morning to boost the batteries and than shut it off and let the solar top it up to 100 soc, what do you think.
Dave

[sensij]

Yes, you are getting it! You may already be familiar with it, but for reference, here is the SOC vs specific gravity table that Trojan includes in their FLA user's guide.

SOC.JPG

(there is temperature compensation to consider too, but I'm going to assume you have that covered)

At 1.240, you are just over 80% SOC. At 1.225, you are at around 70%. The good news is that your loads is small enough that you aren't over discharging, but the bad news is that if the batteries never get to 100% SOC, sulfation will still be a problem.

I think your plan is a good one... using the generator in the morning when high current can be accepted by the battery should be an efficient use of fuel, and transitioning to absorb in the middle of the day when solar is most productive gets the good out of your panels when the high current isn't so important.

With more or higher rated panels, you *should* eventually be able to drive the voltage up to 14.8 (or higher) and hold it there using only PV, but as your system is now, it would probably take a couple days of charging with very little consumption.

Yes, the SOC reported by the charge controller is not worth much, it is a problem with any system that tries to guess SOC on lead acid using only voltage. As we've already covered, voltage alone can be really misleading. Once you figure out a routine that regularly gets you to 100% SOC based on the specific gravity reading, you'll be in a better position to figure out how much more solar you should be adding, relative to the cost and effort to run the generator. If you add enough panel capacity, you might find that a 60 A or 80 A charge controller is a worthwhile upgrade. A pair of 40 A Tracers might be ok too, and lighter on the wallet, although the 100 Voc limit will be constraining at some point.

[littleharbor]

That particular charge controller does have a 100 Voc limit although tracer does make 150 volt versions as well.

[Loveshack]

Thanks for your time and patients. I feel like I have a much better grasp of my new solar system.
Dave

[indygreg]

the internet is awesome - i found this post and i think it is exactly what is happening to me. i have an solarepic 40 amp controller and 4 lensun 100W panels on the roof of our van. I have 4 fullriver dc150-12 batteries and a xantrex freedom 3000 inverter/charger. when the solar was first installed and the inverter was turned off i saw the voltage go up into the mid 14's (i set it to boost at 14.7 and float at 13.7). then when i turned the inverter on and powered up the fridge i never saw the voltage get over 12.5. the inverter draws 4 amps at idle (wow that was a surprise) and the fridge draws .4@110vac so about 4 amps also. so on a sunny day i suspect the 8 amp draw is not leaving enough current to get the battery charged.

so i don't really have room for more panels. i think i will have to look at the solar as a range extender and continue to charge from the wall or the engine (i have a second inverter on the engine that fees 110VAC to my xantrex charger). i know that charging with the xantrex is doing a proper 3 stage charge where this solar controller seems less sophisticated. i see my voltage climb to over 14V if the sun comes out while my van is plugged in a charging so even though the xantrex has the battery fully charged and in float stage, the solarepic will start boosting. today i put a relay on the solar power input to the charge controller so that if i am charging off the xantrex the solar is disabled. my batteries are VERY hard to replace so i want to take no chances with them.

on the plus side we tailgated the purdue game last week and i arrived fully charged in the morning and at night i was still at 100% due to the solar system. i had hoped to never plug in again but i will have to settle for having the solar be a backup to my main charger i think.

greg

[Loveshack]

Just of a bit of an update. On the 28 th Day my mppt was to equalize my batteries at my preset 15.6 v. It was a cloudy day and I was off grid. I monitored the mppt for the day and the voltage was unable to reach my preset of 15.6v. I week later I was plugged into shore power so my batteries were topped right up. It was a sunny day and the mppt equalized my batteries at 15.6 for the set 180min. I was glad to see that the mppt eventually equalized when the conditions were right.