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. Cro...
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"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
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
