healthy float time

mahendra
mahendra Solar Expert Posts: 177 ✭✭✭
hi .i know longer the battery stays in float is better .but how much time(hours ) is considered a healthy float time.:D

Comments

  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    Re: healthy float time
    mahendra wrote: »
    hi .i know longer the battery stays in float is better

    I'm not sure that is true. Why do you think so? Some battery manufacturers (traction batteries) recommend NOT to float their batteries.

    Anything that elevates a battery's voltage (after it is fully charged) is not good for the battery. The best reason to float a battery, in my opinion, is so that your charge controller can pick up loads without discharging the battery.

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • mahendra
    mahendra Solar Expert Posts: 177 ✭✭✭
    Re: healthy float time

    i do not have traction batteries i have 8d
  • waynefromnscanada
    waynefromnscanada Solar Expert Posts: 3,009 ✭✭✭✭
    Re: healthy float time
    vtmaps wrote: »
    The best reason to float a battery, in my opinion, is so that your charge controller can pick up loads without discharging the battery.

    --vtMaps

    Well said vtmaps, and with regard to off grid systems, you hit the proverbial nail on the head.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: healthy float time

    There is no minimum time requirement for Float at all. It is not part of recharging per se. As vtMaps said, it just allows panels to power the loads giving the batteries a rest.

    This is not the same issue as batteries that are on standby all the time and not cycled, where continuous floating can actually be detrimental to them. Some batteries are better able to handle that situation (as in those used in UPS units and telecom applications).
  • NorthGuy
    NorthGuy Solar Expert Posts: 1,913 ✭✭
    Re: healthy float time

    You do not really have any control on how long the float is.

    If there's no float, the system is probably undersized. If it is too long, the system might be oversized.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: healthy float time
    NorthGuy wrote: »
    You do not really have any control on how long the float is.

    You can in a round-about way: adjust the Float Voltage setting up to where the panels can't maintain it very long and/or increase the Absorb time. But you're right that most controllers do not have a Float time setting.
    If there's no float, the system is probably undersized. If it is too long, the system might be oversized.

    Clarification: time will vary from day to day with operating conditions. if it never sees Float it's undersized. If it's in Float most of the day every day it's oversized. Most of us don't have enough hours of good sun to suffer from that phenomenon. :D