• Load Anomalies

    **27th Feb** See https://disqus.com/home/discussion/victronwiki/victronconnect_manual_12/newest/
    The problem arose that the Load reading was incorrect and didn't seem to work. On 28th I assessed it was reading some 0.6A low so if I wasn't using much it appeared as there was no load. I disconnected the MPPT after sunset on 28th Feb and all seems OK again.

    **9th Feb** See image [histFeb9,gif] It seems as though as the current increases the MPPT becomes less efficient to a degree of 90%. 100w was used during the day of 1.21K yield though there was little load.

    **Today the 8th Feb** I recorded 240W usage from the previous day, most I expect from the late afternoon through to midnight: so maybe 8hr @ 30w more than double what I expected. So today I have noted 30w usage by 16:00 and have loaded (comp, router, led4, phone) which is Victron Connect reads as 1.3 amp. Will leave on until midnight and expect 8 x 1.3 x 12.5w or 130w + 30w for a total of 160. Let's see :)
    **23:50** consumption 130w total So 30w before 16:00 and 100W over 8 hours with computer router and led4 for 8 hours (12.5w/h :: 1A x 12.5V)

  • Absorption Time

    The most important part of the charge cycle is the absorption charge. Since the bulk charge only recharges the battery bank to an 70-80% level, the absorption charge completes the charging cycle.
    If the absorption charge is not completed fully a part of the battery plates will not cycle and are likely to become sulfated, which in turn leads to shorter period of bulk charging until the absorption level is reached. If this is done often then the battery will loose capacity and it can be quite dramatic in that after a few months it may be reduced to 50% capacity. One process to remove sulfation is to over-charge or use an equalisation voltage once the battery appears charged.

    Some chargers have a timer that allows the user to adjust the duration for the required time to return the battery to full charge. In order to set the correct time, a simple calculation is required. With the help of the 20 AH capacity, you can figure out the remaining charge required for the battery bank using the following equation:

    If the actual absorption time is significantly less than as calculated below then the likelihood is that the battery has reduced capacity.

    If a charger measures the standing voltage, for example after 12 hours of no load, it may adjust the time of absorption noting the battery is nearly fully charged. This again can be misleading as a sulfated battery not only will have reduced capacity but a higher resistance and so the voltage will appear high when there is little charge in terms of capacity.

    t = 0.42 x (C/I) and with an 80% charge

    t = Absorption Charge Time (Hours)

    C = 20 hr Rated Capacity (AH) [ex: 2 strings x S-550 models (428 AH) = 856 AH rated capacity]

    I = Charging Current (Amps) [charger output min 5% up to max 10% of 20 hr rate]

    **Example** For a single 120Ah battery charging at 12amps that equates to 0.42*(120/12) which is 4.2 hours and I doubt I reach half of that. Given that the recommended voltage is over 15v I have developed quite a problem maybe using 14.5v Oops!

    Good info on https://en.wikipedia.org/wiki/Lead%E2%80%93acid_battery :: wikipedia Lead acid battery

  • Basic configuration

    The Electric Control brings together the inputs from solar panels via terminal, where adjustments can be made, to charge controllers that feed the batteries. The main update for 2018 is the terminal blocks that allow the solar panels to be connected separately to two banks of batteries, and be connected in parallel or series and bypass the controllers to fed the batteries directly.
    [center]![control panel with MPPT](https://calstock.org.uk/media/blogs/elf/img/posts/new_electrics/elec_panel.jpg "null")[/center]

    Pages: 1· 2

  • Battery Loads

    1. Router 0.35A | Computer 0.4A | LEDs (7W 0.3, 4W 0.2, 1W 0.05)A
    * Computer charging screen battery and running 6W
    * Samsung III 5W
    * Inverter with audio amp and standard plugs 40W

    With all powered on, current draw is 1.2A: so for 8 hour is 96W is used.

    Solar panels can produce 250w per hour so in the summer one hour will provide more than double than and there is less used.

    **Feb 5th-6th** Left router on for 24hrs and 50W used
    **Feb 24th-25th** Left router and camera on for 9hrs and 70W used

  • Diary 2018

    **Feb 2018**
    **1st** 08:40 V=12.71 :: Charge at >15V from to 11:55 to 15:35
    **2nd** 02:05 V=12.69 :: 10:00 V=12.64 :: 10:25 On charge V=15.47
    **3rd** 00:40 V=12.80 :: 09:20 V=12.72 :: Charging today
    **4th** 10:35 V=12.72 :: Charging 6hr >15V
    **5th** 07:40 V=12.69 :: Charging Float 3hr @ 15.4V :: 15:53 V=14.6 Disconnect
    **6th** 16:45 V=12.69
    **7th** 06:20 V=12.64 :: 09:05 Charge :: 09:07 V=15.92
    **8th** 16:45 V=12.67
    **9th** 08:50 V=12.61 :: 10:01 Charge V=15.45
    **10th** 08:10 V=12.72 Gone to Gavin's around midday for continuous mains charging at 14.6V for a couple of days
    **15th** 08:30 V=12.86 @ Gavin's 09:30 V=12.67 with my meter. Now permanently connected to Batt 4. Which are connected to Batts 2 and 3 and at 12:30 V-15.33

    Pages: 1· 2

  • Diary 2018 :: 02~Feb

    **1st** 08:40 V=12.58 :: 17:30 V=12.7 without load with comp, router and 4w LED V=12.6
    **2nd** 02:05 V=12.71
    **3rd** 00:40 V=12.71 ::09:20 V=12.67 :: Charging
    **4th** 00:01 V=12.51 :: Charging 6hr >15V
    **5th** 07:40 V=12.71 :: Charging until 12:40 BLK/ABS/Float 2h36 at 14.5
    Changed Abs to 15.94 and Float to 15.4v
    **6th** 08:00 V=12.48 (left router on all night) :: 16:45 V=15.4 Charging 6hr >15V
    **7th** 06:20 V=12.79 :: 09:05 V=15.92 ABS (no direct sun until 9am) Used 240 watts
    **8th** 00:00 V=12.52 :: 13:30 V=14.50 @ 3A :: W=46 Y=100 :: On-line for 1 hour
    **9th** 08:20 V=12.52 :: Charged >15.4 >5 hr :: On 1.1A load for 7hr
    **10th** 08:20 V=12.67 :: Cloudy minimal charge and on load :: Moved to backup did reach ABS at new setting of 15.64V
    **11th** 00:35 V=12.73 :: 09:50 has reached new ABS at 15.64 but frequent heavy cloud and yield has dropped to 0 for a second or two.
    **12th** 00:35 V=12.73 :: 08:23 V=12.73 :: 09:02 charging @Abs at 15.63
    **13th** 00:10 V=12.81 :: 09:47 V=12.69 :: On charge
    **14th** 01:00 V=12.86 :: 09:47 V=12.74 :: 21:00 V=12.64
    **15th** 09:30 V=12.61 :: 12:30 V=15.33 :: On charge