Absorption Time

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Comments

  • Surfpath
    Surfpath Solar Expert Posts: 463 ✭✭✭
    Re: Absorption Time
    NorthGuy wrote: »
    On full charges, I run absorption at 64V to the point where I belive SG is full. Takes 5-7 hours of absorption. On Nov 23 it took 6 hours 40 minutes. You can call it equalization.

    Looks similar to what you're doing :D

    Hi North,
    I'm fortunate to have pretty regular longish amounts of sunshine. In fact I haven't used the generator in 4 months (er...that's right I can't use it because it's still at the dealership broken:cry:).

    On your regular charge cycles what are your Absorb times? Are they also ~6 hours using sun + then genny?

    If on Nov 22 you charged to 71% SoC what was your SOC reading the next morning? Must have been low.

    I absorb at about 59.3V (to 59.6V) typically. This helps to slow down Trojan's or Outback's diminishing returns.

    Still don't know which bit of gear to blame. Maybe it's me ;)
    Outback Flexpower 1 (FM80, VFX3048E-230v, Mate, FlexNetDC) 2,730watts of "Grid-type" PV, 370 AmpHrs Trojan RE-B's, Honda 2000 watt genny, 100% off grid.
  • NorthGuy
    NorthGuy Solar Expert Posts: 1,913 ✭✭
    Re: Absorption Time
    Surfpath wrote: »
    On your regular charge cycles what are your Absorb times?

    Daily? Zero. It goes to 58V and stops. I look at it as not doing absorption.
    Surfpath wrote: »
    If on Nov 22 you charged to 71% SoC what was your SOC reading the next morning? Must have been low.

    Depends on the weather. They discharge more in the cold, less in warmer weather. Lately a typical nightly drop has been about 30% (200AH), so that day it probably was somewhere around 40% SoC next morning. Theoretically, my cycling is between 20% SoC and absorption, but in reality it doesn't go below 30-40% often. It only did that, may be, 5 times since September.
    Surfpath wrote: »
    Still don't know which bit of gear to blame. Maybe it's me ;)

    Definitely Trojan. I believe their batteries are designed for backup systems where you can do long charges from the grid. Not good for off-grid. Not in the North anyway. The only hope that they will last as long as advertized.
  • YehoshuaAgapao
    YehoshuaAgapao Solar Expert Posts: 280 ✭✭
    Re: Absorption Time

    I'm not off grid, but since I'm using off-grid batteries, I cycle them every other sunday late afternoon through monday mid morning (by flipping off the grid circuit breaker). I've been noticing longer absorption times as the weather gets colder.