ATS + generator = ac power + battery charge? possible?

2»

Comments

  • Wheelman55
    Wheelman55 Registered Users Posts: 232 ✭✭✭
    minisolar said:
    Thank you Wheelman. Will this one work as well?
    https://www.amazon.com/dp/B07FGFFHC6/ref=cm_sw_r_apa_i_gQM1EbQNC7XN7

    I see mentions of a tester... For the batteirs. Another device. Is that something I need as well? 
    oughta work AOK.  all you really need is voltage. 
    Off-Grid in Terlingua, TX
    5,000 watt array - 14 CS 370 watt modules. HZLA horizontal tracker. Schneider: XW6048NA+, Mini PDP, MPPT 80-600, SCP. 390ah LiFeP04 battery bank - 3 Discover AES 42-48-6650 48 volt 130ah LiFePO4 batteries
  • minisolar
    minisolar Solar Expert Posts: 158 ✭✭
    That monitor will arrive end of July the earliest and as late as mid august... I tried finding it in other places to no avail. 

    How about this one: https://www.ebay.com/itm/DC-Multimeter-Battery-Monitor-200V-10A100A300A-Current-Voltage-Solar-Power-Meter/184044878906?hash=item2ad9edfc3a:m:m2aWGshvHgFoVIE40heXsAA

    This is the wiring diagram for it. Seems odd that it needs external power? https://wxalbum-10001658.image.myqcloud.com/wxalbum/217684/20191121172436/17f66a9c382478f8f5a1edadb905e708.jpg

    If you guys think it is good I will order it asap and hope it arrives soon. 

    Bill - any thoughts on my batteries? if I should go with 4 batteries or 6? 

    Also, assuming I get that freezer I linked to. It has no drain hole which is where I was hoping to insert probe fro the thermostat to convert to fridge. I saw that others are drilling a hole in their fridge - can I do that? How likely I am to hit something? is there a place that for sure I won't have an issue to drill? 
  • BB.
    BB. Super Moderators, Administrators Posts: 33,422 admin
    The BMS needs >8 volts to run its computer... And it also needs to measure the battery voltage to figure out state of charge too--That are two functions for the battery/+12 volt connection. The shunt is basically near zero volts because it is on the ground lead (and ~0.100 volts or so maximum across the shunt terminals).

    The other power terminals are to run the BMS computer if you are running, for example, on a 6 volt battery bank.

    How much energy (WH or AH @ 12 volts) do you want to draw from the bank? And how deep of daily discharge (discharging to 50% is certainly OK for RV use... However, the (FLA) batteries take hours longer to recharge vs only using 25% of capacity (bulk and absorb times longer the deeper the discharge).

    Also, what charging current (from genset/solar) are you planning on designing for? I try to suggest that people do not oversize the battery bank (cost more, needs higher charging current, etc.).

    For RVs, the batteries generally age out before they cycle out--So deep discharging is not a huge issue on weekend RVs for 50 Weekends a year--Other than the time to charge (more genset run time if no solar).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • minisolar
    minisolar Solar Expert Posts: 158 ✭✭
    edited June 2020 #35
    I realized both those cheap monitors which seem good - don't have alarms fro low voltage which is important to me as a solar rookie. I think I just need to bite the bullet and get that $100 renogy monitor. It has programmable low voltage and alarm. Agreed? 
    https://www.amazon.com/Renogy-500A-Battery-Monitor-Programmable/dp/B07RP5B5P7

    I don't know my loads yet so not sure how much I will draw but will try to stay above 60% then charge with the generator. 
    Wheelman estimated that it will take around 10 hours to charge with my generator - my plan is to start it up before we go to bed (with the kids at 8pm haha). Then we usually get up around 7am so that will be 11 hours of charging... This should give me fully charged batteries for the day so we don't have to listen to honda. I will not run ac on batteries ever. So my biggest daily draw by far will be my (hopefully) solar converter fridge. I will need to play and learn my usage to realize when I need to plug in generator and when I can let it run by itself. 

    Which is why a battery monitor with alarm sounds good. 
  • minisolar
    minisolar Solar Expert Posts: 158 ✭✭
    I am finalizing my system and plan on doing what Macgyver outlined.. 

    What I realized yesterday is: The honda generator has a built in inverter and so let's say I hook up my generator up, with eco mode off, to my system so it feeds my distribution box and iota to charge batteries at the same time via ATS -as Macgyver outlined - then wouldn't the iota call for max power from the honda but also the distribution panel call for some power (ac [400w], fridge [300w], rv pump when activated, and so on) so wouldn't this cause the generator to feel like it is overloaded and shut off? 

    What will cause the power from the generator to be distributed between distribution panel and iota in a way so it doesn't overload and shut off? 


  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    You must use a generator that can manage 130% of the loads you apply to it.   

    Or you can use a small generator, and a hybrid inverter that has Generator Support, where the inverter takes over loads when the generator is near its limit.

    there is no way to have the iota throttle back its charging when the generator is overloaded, that has to be addressed in the system design stage, to not allow the generator to overload

    Tricky stuff, and the least expensive failure mode is simply a power outage. 
     Or you BBQ the small generator to death. Or your air conditioner dies from brownout conditions.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,