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pirlbeck's avatar
pirlbeck
Explorer
Apr 26, 2018

Victron 75/15 and Crown 31DC130 settings.

I have a Victron 75/15 charge controller with 200w of solar and a pair of Interstate 31TMXU which are Crown 31DC130 batteries. Here are a couple of links to literature on these Crown batteries.

Crown 31DC130 info 1

Crown 31DC130 info 2

The second one lists renewable energy charging guideline.

Daily charge (absorption) 15V
Equalize 15.6V
Float 13.5

The controller has a setting for bulk charge, but I see no mention of a bulk charge voltage in any of the Crown info. Also I need a setting for the number of hours in absorption.

I also have a question about equalization. As this camper is usually plugged in when stored should I turn equalization off and just let the PD9200 converter handle it?

Thanks!
  • OK, it looks like the link above for info 1 is the one I need to use. As posted above my batteries are not a "true" deep cycle battery.

    I spent some time looking around at the different charge profiles on this charge controller. Here is a list of the 8 battery presets.

    AGM Spiral cel

    Gel Victron deep discharge (1)

    Gel Victron deep discharge (2) (This was the default setting and the one that is still selected)

    Gel Victron long life (OPzV)

    Lithium Iron Phosphate (LIFePo4)

    PzS tubular plate traction (1)

    PzS tubular plate traction (2)

    PzS tubular plate traction (3)


    Here are the settings for the Gel Victron Deep discharge (2) preset that I have selected.

    Absorption voltage -14.40 V

    Maximum absorption time - 6h 0m

    Float voltage - 13.80 V

    Equalization voltage -16.20 V

    Automatic equalization - disabled

    Manual equalization - this has a "START NOW" button.

    It looks to me like this setting should be pretty close other then needing to turn equalization on.

    Opinions????

    Thanks!
  • Inherently the 31 jar is an acid starvation design when flooded. It has an industry bad-boy reputation. The same, to a limited degree can be said of the 1275 jar - in comparison to say an L-16.

    With flooded designs, surplus acid is always superior.

    Claims without supporting kWh transactions are not valuable. I purchased a used car, 12 years old with the factory tires and battery. That must mean the OEM battery and Goodyear tires are outstanding? Maybe the 13,000 miles on the odometer had nothing to do with it?
  • Smitty77 wrote:

    Be interested to have you share your experiences with the Crown. Some reading reveals positive, and I believe one member on this forum had a 'It's OK.' comment about a Grp 31 Crown he had bought. The more info actual users share, the more we will all learn about Crown's.


    I have two Crown CR-240's, I've had them a little over a year and they perform admirably.
  • When hard nosed camping how often does the controller end up at float each day? If every day with a small battery bank, you're living right. Even once-a-week would be wonderful. Once-A-Never is a whole different animal.

    If NEVER pops up, then the bulk-absorb-float question only applies when the unit is in storage.
  • Thanks for the replies!

    Getting access to the battery fill caps is not an easy deal, so regularly checking the specific gravity or looking for bubbling cells is not going to be possible on a regular basis. The battery in the OE location must be removed from the compartment to access the fill caps and I only do that a couple times a year to check the electrolyte level. I will check specific gravity when I service it this spring. The second "add on" battery is located in the LH front corner of the bed and is not accessible when the camper is on the truck.

    Now back to the original question.......solar charger settings.

    Bulk set at?? 15V or does it need to be higher???????

    Absorb 15V

    Equalize 15.6V

    Float 13.5V

    I don't think the max amp values can be set on this controller and it is probably not an issue with only 200 watts of solar.

    Thanks again!
  • Computers, flamenco dancers and 3100 people who agree with you on a forum does not begin to equal reality.

    Unless ALL CELLS in a battery are bubbling slightly no solar on the face of the earth is allowing a full charge. Setting a charger to 1 amp then allowing it to charge day and night may allow a full charge with a minimum of bubbling in the cells. If the battery was never allowed to discharge very low amperages would do this over time. But that isn't reality.

    Is is so easy to check for bubbling at solar day's end. And dip with a hydrometer if in doubt.
  • "bulk" is the charging battery voltage up untill it reaches absorption voltage. manufacturers seems to like to use terms however they want and confuse the matter, in their quest to outmarket each other.

    I used to get crown group27's. I did noo get great life from them but was not charging them properly either and then not watering them in time.

    While the battery says commercial deep cycle, the problem is is that no flooded group 31 battery is really a deep cycle battey, compared to a GC-2 golf cartbattery, plates are half as thick, if that.

    They are marine/ dual purpose batteries no matter what they are chosen to be called by the manufacturers or retailers, and they will not last as many deep cycles as a true deep cycle battery. They are also harder to fullly recharge seemingly requiring insane voltages held for much longer to max out specific gravity.

    My most recent flooded battery is a USbattery group 31, same specs as that crown. Same casing and handle design too, but blue insted of black.

    It was petulant, and through trial and error and a lot of hydrometer dipping I found the sweet spot absorption voltage was 14.9v, for a few hours then i set float to 15.3v for the rest of the afternoon.

    Even with this regimen the SG would walk down each cycle and after about 15 I would need to set Absorption to 16v and it would take abou 45 minutes for SG to max out on all cells. Without the 15.3v float, the 16v EQ charge would take close to 4 hours before SG maxed out.

    I got close to 500 deep cycles from it before removing it from my rig. It still lives on the floor of my workshop powering LEDs and fans and is just shallowly cycled and a 100 watt panel does its thing at 14.7 and 13.7 with a temp sensor on the battery. Should probably check the water level soon.

    Get a turkey baster style hydrometer, check SG when the solar controller says it is done and goes to float. Hydrometer will not agree, bump up absorption voltage and duration until it does, or nearly so.

    The depth of your cycles will have a huge effect on what absorption voltage is required and for how long, and 200 wats of solar for 260Ah of battrey is too little if cycled below 75% SOC
  • On Bulk, suspect the same voltage as Absorb would serve you well. Amp hours would be best if coming in at between the mentioned 10 - 20% range of your batteries rating. So 13-26Amps range, if you have settings to control amp values. I'd probably start 17-18Amps, and see how that works. Bump up or down, based upon your usage and what you're seeing on recharge times. If the batteries are not outgassing too much, then bump them up to the 26Amps and see how things go. (The higher the Amps, the faster the Bulk will finish and get you into the Absorb mode. With solar, faster is better, as you never know when clouds may come in:)!).

    Be interested to have you share your experiences with the Crown. Some reading reveals positive, and I believe one member on this forum had a 'It's OK.' comment about a Grp 31 Crown he had bought. The more info actual users share, the more we will all learn about Crown's. (I looked closely at the AGM's, but due to some assistance on replacement costs, retained Lifeline's. And no complaints on Lifeline's from my viewpoint. Good company, backs their products, and helps their customers...).

    Best to you,
    Smitty

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