02-27-2018, 10:25 PM
Well, one would hope if they are out of stock they would not still be selling them and 'pending' charging accounts.
Perhaps I put in the incorrect Email address. Can't remember if I were drinking on Saturday when I ordered. that probably means yes.
This controller basiclly stays in Absorption voltage for 2 hours, once the solar can get the batttery there, and of course if the solar can keep it there for the 2 hours.
Whether 2 hours will be enough can make or sulfate any specific battery and battery capacity. I feel this controller is good enough for my workshop battery. I feel it is good enough for running in parallel with my BlueSky sb 2512i MPPt controller through bulk and early absorption. I would not expect it to be good enough for batteries at half their life and still seeing 50% overnight depth of discharges.
How long to hold absorption voltage is kind of tricky. a simple 2 hours can be 2 hours too little, or one hour longer than required. So many variables.
Those with flooded batteries can dip a hydrometer see if the specific gravity indicates full or nearly so. Those with AGM need to monitor amperagre into the battery at absorption voltage, not float voltage., should they wish to confirm the battery is fully charged.
Oftentimes one needs to be smarter than the controller/ smart charging source, and trick it into reseeking absorption voltage. not always possible, certainly not desirable from a labor viewpoint.
Or one can just ring the 'just fine' bell. they day when it is no longer 'just fine' can be tomorrow, or some acceptable point in the future.
i just feel it is a crime when solar wattage is avalable to hold the battery at absorption voltage, but the controller decides prematurely that everythig is just fine, when the battery wants more time at absorption voltage.
Generally the lower and sloer the rate at which solar gets the battery to absorption voltage, the less time it need to remain at absorption voltage, and the higher the amperage rate at which the battery achieves absorption voltage, the longer from that point it needs to be held.
100 amps can get a depleted battery to absorption voltage instantly, and amps will instantly start tapering, but full charge could take 6.0 more hours when held at absorption voltage.
10 amps might get the same depleted battery to absorption voltage in 4.5 hours, and then 2 hours more held at absorption voltage might be required to fully charge the battery, or it could be 4 hours more.
Better solar controllers see how much amperage the battery is accepting( not also powering loads), and have a programmable number that once it tapers to to trigger float voltage/
Some others have hours to hold absorption voltage. Some use both.
It is the duration at which absorption voltage is held, which will define battery life in deep cycle service, followed by the average temperature of the battery, and then the average depth of discharge. This assumes the battery is not drained to 20% and then left to sit for a week befire recharging. that is a battery killer far and above unideal in the other factors.
2 hours absorption could be good enough, or no where close to it.
But any recharging is better than no recharging, and for 20$ this controller shiould be a good deal, . I would just recommend those getting expensive battery banks, and wanting good longevity from them, get a controller whose absorption voltage duration can be programmed.
A digital Ammeter showing amps into the battery bank ( not just total solar output, as this ignores loads on teh dc system at the time) at absorption voltage. a 100Ah wet/flooded marine battery held at 14.7v will be fully charged when the amperage it is accepting is in teh 0.8 to 1.2 amp range, and this will change when new as opposed to cycle number 500, of one actually gets such a battery to 500 deep cycles, which would be not so common.
Perhaps I put in the incorrect Email address. Can't remember if I were drinking on Saturday when I ordered. that probably means yes.
This controller basiclly stays in Absorption voltage for 2 hours, once the solar can get the batttery there, and of course if the solar can keep it there for the 2 hours.
Whether 2 hours will be enough can make or sulfate any specific battery and battery capacity. I feel this controller is good enough for my workshop battery. I feel it is good enough for running in parallel with my BlueSky sb 2512i MPPt controller through bulk and early absorption. I would not expect it to be good enough for batteries at half their life and still seeing 50% overnight depth of discharges.
How long to hold absorption voltage is kind of tricky. a simple 2 hours can be 2 hours too little, or one hour longer than required. So many variables.
Those with flooded batteries can dip a hydrometer see if the specific gravity indicates full or nearly so. Those with AGM need to monitor amperagre into the battery at absorption voltage, not float voltage., should they wish to confirm the battery is fully charged.
Oftentimes one needs to be smarter than the controller/ smart charging source, and trick it into reseeking absorption voltage. not always possible, certainly not desirable from a labor viewpoint.
Or one can just ring the 'just fine' bell. they day when it is no longer 'just fine' can be tomorrow, or some acceptable point in the future.
i just feel it is a crime when solar wattage is avalable to hold the battery at absorption voltage, but the controller decides prematurely that everythig is just fine, when the battery wants more time at absorption voltage.
Generally the lower and sloer the rate at which solar gets the battery to absorption voltage, the less time it need to remain at absorption voltage, and the higher the amperage rate at which the battery achieves absorption voltage, the longer from that point it needs to be held.
100 amps can get a depleted battery to absorption voltage instantly, and amps will instantly start tapering, but full charge could take 6.0 more hours when held at absorption voltage.
10 amps might get the same depleted battery to absorption voltage in 4.5 hours, and then 2 hours more held at absorption voltage might be required to fully charge the battery, or it could be 4 hours more.
Better solar controllers see how much amperage the battery is accepting( not also powering loads), and have a programmable number that once it tapers to to trigger float voltage/
Some others have hours to hold absorption voltage. Some use both.
It is the duration at which absorption voltage is held, which will define battery life in deep cycle service, followed by the average temperature of the battery, and then the average depth of discharge. This assumes the battery is not drained to 20% and then left to sit for a week befire recharging. that is a battery killer far and above unideal in the other factors.
2 hours absorption could be good enough, or no where close to it.
But any recharging is better than no recharging, and for 20$ this controller shiould be a good deal, . I would just recommend those getting expensive battery banks, and wanting good longevity from them, get a controller whose absorption voltage duration can be programmed.
A digital Ammeter showing amps into the battery bank ( not just total solar output, as this ignores loads on teh dc system at the time) at absorption voltage. a 100Ah wet/flooded marine battery held at 14.7v will be fully charged when the amperage it is accepting is in teh 0.8 to 1.2 amp range, and this will change when new as opposed to cycle number 500, of one actually gets such a battery to 500 deep cycles, which would be not so common.
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