Please Explain SW 4024 AC Qualify Time Setting

MrM1MrM1 Registered Users Posts: 450 ✭✭✭
I get the basic idea,  but it is not in the manual of either the User guide for the SW or the Combox.  It is set in seconds and is the time it takes the SW to qualify AC input from the grid or a generator.  Mine is set to 10 seconds. 
What i don't understand.  Today I connected a 4000w 120v Inverter generator to the SW thru the house main panel on L1 only.  Turned off grid power,  started the generator and the SW qualified the power from the generator in 10 seconds.  The SW is able to take the 120v coming into the inverter and output it as 120v on both L1 and L2 as it is supposed to do.  And I am able to charge from the generator using the SW charger albeit at a 50% charge reduction - again as the SW is supposed to do.  So good so far.
But with the SW being powered from the generator and not drawing off batteries at all,  with a 600 W load things are good.  But the moment my well pump kicks in (a 240v 800W load),  the inverter switched to battery as though the generator or grid went down,  but only for about 10-15 seconds.   It seems the AC in from generator gets "lost" and has to be qualified again.   But the generator's RPM has increased,  and in about 10 seconds the inverter switches back to generator power and stops drawing power from the batteries.
I am guessing this is because:
1. my generator cannot respond fast enough to the pump start surge thus the SW "thinks" I lost power
2. My 10 second AC Qualify Time is causing the SW to run off batteries at the start up of the pump
So I am wondering,  What is the point of the AC Qualify Time?  Should it be set to a short time or a long time?   There is no info in the manuals about it (unless its in the SW install manual).  Could I set that AC Qualifying time to 0 and then the SW would not switch from generator to batteries and back to generator when running on generator and a large surge load starts up?   Or would that be too hard on the SW's internal contactors as it might jump back and forth from generator AC in to battery in at large startup loads until the generator is able to stabilize ?
REC TwinPeak 2 285W 3S-3P 2.6kW-STC / 1.9kW-NMOT Array / MN Solar Classic 150 / 2017 Conext SW 4024 Inverter latest firmware / OB PSX-240 Autotransfomer for load balancing / Trojan L16H-AC 435Ah bank 4S connected to Inverter with 7' of 4/0 cable / 24 volt system / Grid-Assist or Backup Solar Generator System Powering 3200Whs Daily / System went Online Oct 2017 / System, Pics and Discussion

Comments

  • MrM1MrM1 Registered Users Posts: 450 ✭✭✭
    Or maybe it would be better to set the AC Qualify Time to longer than 10 seconds to give the SW less of a chance to bounce back and forth between Grid/Gen and Battery?  So the SW would run off battery longer
    REC TwinPeak 2 285W 3S-3P 2.6kW-STC / 1.9kW-NMOT Array / MN Solar Classic 150 / 2017 Conext SW 4024 Inverter latest firmware / OB PSX-240 Autotransfomer for load balancing / Trojan L16H-AC 435Ah bank 4S connected to Inverter with 7' of 4/0 cable / 24 volt system / Grid-Assist or Backup Solar Generator System Powering 3200Whs Daily / System went Online Oct 2017 / System, Pics and Discussion
  • Dave AngeliniDave Angelini Solar Expert Posts: 4,665 ✭✭✭✭✭
    Try it
    "we go where power lines don't" Sierra Mountains near Mariposa/Yosemite CA
     http://members.sti.net/offgridsolar/
    E-mail [email protected]

  • MrM1MrM1 Registered Users Posts: 450 ✭✭✭
    OK. I just didn't want to do it if there was some electrical reason I should not. Looks like I'll have plenty of time to try it early next week. 
    REC TwinPeak 2 285W 3S-3P 2.6kW-STC / 1.9kW-NMOT Array / MN Solar Classic 150 / 2017 Conext SW 4024 Inverter latest firmware / OB PSX-240 Autotransfomer for load balancing / Trojan L16H-AC 435Ah bank 4S connected to Inverter with 7' of 4/0 cable / 24 volt system / Grid-Assist or Backup Solar Generator System Powering 3200Whs Daily / System went Online Oct 2017 / System, Pics and Discussion
  • mcgivormcgivor Solar Expert Posts: 3,074 ✭✭✭✭✭
    The likely cause is imbalance due to the 120V feed in from the generator, if the generator were 240V the feed through would support the pump without having to resort to drawing from the battery. 
    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery bank 
    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah FLA 24V nominal used for water pumping and day time air conditioning.  
    5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
  • MrM1MrM1 Registered Users Posts: 450 ✭✭✭
    So other than the fact momentary lapse for the surge and waiting for the the AC to qualify, does it hurt any thing? Is it stressful on the SW? Once it qualifies it does settle in and work fine after the start surge. 

    Good news is, I do have an inverter compressor 
    REC TwinPeak 2 285W 3S-3P 2.6kW-STC / 1.9kW-NMOT Array / MN Solar Classic 150 / 2017 Conext SW 4024 Inverter latest firmware / OB PSX-240 Autotransfomer for load balancing / Trojan L16H-AC 435Ah bank 4S connected to Inverter with 7' of 4/0 cable / 24 volt system / Grid-Assist or Backup Solar Generator System Powering 3200Whs Daily / System went Online Oct 2017 / System, Pics and Discussion
  • mcgivormcgivor Solar Expert Posts: 3,074 ✭✭✭✭✭
    The surge would likely occur every time the pump starts, so a second, third or forth cycle would replicate the first. This means the transfer relay is doing extra duty, wether it has a negative impact will be displayed over time. The better solution would be to use a 240V generator to avoid such events in the first place, it may just be me and my opinion but using half of the systems charging capacity is not the best way of doing things. Perhaps others have differing opinions, let's wait to see what they think.
    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery bank 
    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah FLA 24V nominal used for water pumping and day time air conditioning.  
    5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
  • mike95490mike95490 Solar Expert Posts: 8,380 ✭✭✭✭✭
    For under $1K, you can get several decent generators @ 240VAC.   There are few 240VAC inverter generators, and they are pricey.  Do you NEED an inverter genset ?
    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 ,

  • MrM1MrM1 Registered Users Posts: 450 ✭✭✭
    I know about the 240v generator - and no I really dont need the inverter.  But this one was bought in an rush for power for a parade float to be quite, and its all I have right now.  I don't often need it and don't expect to need it now,  it of  a "just in case" thing.   So I may keep the 240v loads off it if I have to use in in a pinch to charge,  and then go back to battery/inverter.  The transfer switch in the SW was my concern and so it may be best to just not stress it.

    I did try reducing the Qualifying time from 10 sec to 5 , and 1 and 0.  And  it does just that.  It qualifies faster,  but still does need qualifying if the 240v load comes on. So I set it back to 10 so the switching is not happening so fast and often.  I suppose I could actually go higher so that a toilet flush (and pump run) would just draw off battery and not try to switch back to AC genny for those shorter bursts. 
    REC TwinPeak 2 285W 3S-3P 2.6kW-STC / 1.9kW-NMOT Array / MN Solar Classic 150 / 2017 Conext SW 4024 Inverter latest firmware / OB PSX-240 Autotransfomer for load balancing / Trojan L16H-AC 435Ah bank 4S connected to Inverter with 7' of 4/0 cable / 24 volt system / Grid-Assist or Backup Solar Generator System Powering 3200Whs Daily / System went Online Oct 2017 / System, Pics and Discussion
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