How to tell if the grid is down with automatic grid tie battery back-up system?

BigfellaBigfella Registered Users Posts: 1
edited December 2015 in General Solar Power Topics #1

I ( and the electrician) just installed a Schneider Conext grid-tied battery back-up system in the basement with PV arrays out in the yard. I really like the system. During simulated grid down tests the switch over to off-grid battery power is 100% seamless. Their is not even the slightest indication that the switch has occurred.

This is great but how will I know the switch has occurred when I am not in the basement? Is their something I can do to too alert me that the grid is down? Alarm? Emergency light? Some sort of light that I could run up from the basement into the house?

Without knowing the grid is down I will not know to move into "off grid power conservation" mode. I could drain my battery bank and not know it until the generator kicks on to recharge the bank (at night)...and hopefully I will hear it.

I am stumped? Any Ideas?


  • Belmont SolarBelmont Solar Registered Users Posts: 26 ✭✭
    Just have some of the lighting circuits powered off of the grid, not off of the inverter
  • BB.BB. Super Moderators, Administrators Posts: 32,601 admin
    Or just power a 120 VAC relay from grid... When fails, relay turns on DC voltage to light/alarm.

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • techntrektechntrek Solar Expert Posts: 1,372 ✭✭✭

    All of my lighting circuits and most other 120 circuits are backed up via UPS so I've considered a similar solution for my own home, but I have more details, below.

    Use a circuit from the inverter which is switched via a normally-closed relay, with the relay powered by a utility-powered circuit.  Power goes out, whatever is on that relay lights up.  Either a 120 volt light, or if it is easier to run low-voltage where you need the light, plug in a 12 volt transformer.  If you drive an LED or two the low-voltage power drop won't be an issue (but you'll need to size the resistor for the LED to account for the LED's load and the voltage drop if you make a long run).

    4.5 kw APC UPS powered by a Prius, 12 kw Generac, Honda EU3000is
  • mike95490mike95490 Solar Expert Posts: 9,571 ✭✭✭✭✭
    Wait for the neighbors to knock at the door or ring your phone.
    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

    gen: ,

  • techntrektechntrek Solar Expert Posts: 1,372 ✭✭✭
    4.5 kw APC UPS powered by a Prius, 12 kw Generac, Honda EU3000is
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