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SkiSmuggs's avatar
SkiSmuggs
Explorer
Aug 24, 2014

Renogy Charger Settings for Trojan T-105

When I first got my Renogy Portable Solar Suitcase, I had a single 12v battery and just hooked it up. Then I started reading the manual and found that the charger had a default battery type of AGM.
After much wrestling with the charger menu system, I found where I could change to Flooded and did that. Then I had a charger fault indication of incorrect voltage. Sure enough, it had somehow been set to 24v while I was thrashing thru the menu. Not knowing what else I had done, I did a factory reset, then changed to Flooded and things were good.
But last week, I upgraded to dual Trojan T-105 six volt batteries. I remembered reading that each manufacturer had their own charging specs and went to Trojan and found the specs were significantly different than your average 12-volt.
Back to the Renogy menu and manual and found I could only change charging parameters by selecting User for battery type. I beat through the settings, changed the charging settings (out of several others) and when I tried to save it, Illegal Parameters! Fired off an email to Renogy, but went back to the manual and menu. I found the Trojan settings exceeded the default limits on a couple of other parameters, made the changes and Success! I have emailed these settings to Renogy for review, but here is what I have for now:

Over Volt.Disc: 16.0v
Charg Lmt: 15.5v (was 15.0)
Over Volt.Rect: 15.5v (was 15.0)

Equal Chrg: 15.5v (was 14.6)
Boost Chrg: 14.8v (was 14.4)
Float Chrg: 13.2v (was 13.8)

Boost V.Rect: 13.0v (was 13.2)
Under V.Rect: 12.2v
Under V.Warn: 12.0v

Low V.Rect: 12.6v
Low V.Disc: 11.1v
Discharg Lmt: 10.6v

Equa. Time: 120
BoostTime: 120

SAVE

18 Replies

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  • SkiSmuggs's avatar
    SkiSmuggs
    Explorer
    Aug 25, 2014
    I don't have a problem with your concerns because I don't know enough to know if the numbers are good or not. I will update once I get a consensus from Renogy and Trojan. However, this is from the Trojan site:

    FOR SOLAR APPLICATION

    Store and operate your batteries in a cool, dry place.
    For every 18° F (10° C) rise above room temperature (77° F or 25° C), battery life decreases by 50%.

    Charge your batteries fully after each period of use.
    Allowing your batteries to sit in a low state of charge for extended periods will decrease their capacity and life.

    If you store your batteries for an extended period of time, be sure to charge them fully every 3 to 6 months. Lead acid batteries will self-discharge 5% to 15% per month, depending on the temperature of the storage conditions.

    Monitor battery voltage and specific gravity of the electrolyte regularly to verify full recharging. As a general rule of thumb, the total amps from your PV panels should be sized between 10% and 20% of the total amp-hours (Ah) of the battery pack.

    Many charge controllers have equalization settings that you can set to help ensure the health of your batteries. Equalize your batteries at least once per month for 2 to 4 hours, longer if your batteries have been consistently undercharged.
    System Voltage
    Volt Settings 12V
    Daily Charge 14.8
    Float Charge 13.2
    Equalize chg 15.5
  • MEXICOWANDERER's avatar
    MEXICOWANDERER
    Explorer
    Aug 25, 2014
    Egads!

    Charging profiles are built upon the ratio the relationship of ampere hour capacity versus charging potential. This has to be further modified to accommodate wide temperature swings.

    Equalization is a controlled charge formula used to correct errant chemistry in cells.

    Absorbsion charge voltage limit for a 5% antimony battery on generator recharge should not exceed 14.8 at 20C

    Absorsion charge time at limit should be variable depending on hydrometer verification after a dozen or so cycles. This is critical.

    Top charge at 5% amp hour capacity to 15.0 volts as needed to reduce frequency need of equalization. Top charging should not be performed on anything but a 100% normally charged battery.

    Equalization is warranted when battery is 100% charged yet a .05 density variance exists between cells.

    I encourage the OP (or anyone else)) to telephone Trojan and discuss the OP's so-called battery charging profile with one of their application engineers.

    A fast rise to 15.0 volts or above is a lot more preferable than forcing the battery to spend hours and hours of time outside of it's voltage pay-grade window.

    I not only doubt but I can be confident that Trojan has not abandoned their specifically derived forumulas for battery recharging. They adhere to the C20 protocol which is used when a battery is recharged under ideal conditions, unlimited time.

    Some of these charge profiles I read are fit for Alice in Wonderland. Instructions configured by Tweedle Dee and Tweedle Dum...
  • time2roll's avatar
    time2roll
    Nomad
    Aug 25, 2014
    How often does it equalize? 120 minutes is good every 6-12 months. I would go shorter if on a monthly cycle.
  • pianotuna's avatar
    pianotuna
    Nomad III
    Aug 25, 2014
    Hi,

    What do you mean by RV controller? If you mean the converter--it will NOT protect the boards from over voltage.
  • SkiSmuggs's avatar
    SkiSmuggs
    Explorer
    Aug 24, 2014
    pianotuna wrote:
    Hi,

    The computer boards in your RV may be damaged by voltages over 15.4. I'd back off the equalize setting to 15.4

    Well done and thanks for sharing.

    I have a question about this. If the solar panel/charger goes direct to the battery, is the built-in RV controller affected by a 15.5v charge? I ask this because I am thinking about the GoPower suitcase with an optional trailer connector option where the charge connects to the trailer pigtail which then goes to the RV controller. I could see where a too high voltage may affect it that way. What do you think?
  • SkiSmuggs's avatar
    SkiSmuggs
    Explorer
    Aug 24, 2014
    Thanks, for the heads up. I'll see if Renogy suggests any changes, then merge them with your suggestion.
  • pianotuna's avatar
    pianotuna
    Nomad III
    Aug 24, 2014
    Hi,

    The computer boards in your RV may be damaged by voltages over 15.4. I'd back off the equalize setting to 15.4

    Well done and thanks for sharing.

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