Where is that bloody low voltage alarm on this old inverter?

I picked up this old marine inverter and opened it up to remove low voltage alarm but didn't find the usual black barrel with the hole in the middle. Can some one help me and point to what to pull out to turn off the annoying beeping sound? Thank you.

Please see pictures
https://imgur.com/og7wN2u
https://imgur.com/g2BEIuW
https://imgur.com/kTViohT

Comments

  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    1) have mercy on us in the boondocks when you upload a multi MB image, you could at least crop it and spare us 8 minutes of loading time.   kTViohT never finished loading.

    My bet is that it's on the panel sharing the end with the power outlet and phone jack and the multi-pin connector, it will be on that board facing the outside world.



    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

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  • Marc Kurth
    Marc Kurth Solar Expert Posts: 1,142 ✭✭✭✭
    You have me curious why the low voltage alarm keeps going off. What voltage is the alarm set for?
    Marc
    I always have more questions than answers. That's the nature of life.
  • mcgivor
    mcgivor Solar Expert Posts: 3,854 ✭✭✭✭✭✭
    edited September 2019 #4
    The warning beeper is there for a reason, either the voltage is too low due to loads being too large for the battery, or the battery voltage is low due to being depleted or both. Sure it may be annoying but its trying to tell you something which needs to be addressed, I'm sure pilots find the terrain warning system annoying at times but it can be helpful in avoiding catastrophic outcomes.


    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery with Battery Bodyguard BMS 
    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.  
    5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
  • Marc Kurth
    Marc Kurth Solar Expert Posts: 1,142 ✭✭✭✭
    edited September 2019 #5
    Let us not forget that inverters are constant wattage devices. As the input voltage drops, the current draw increases.
    I begin to wonder if the original post was done tongue-in-cheek.
    I always have more questions than answers. That's the nature of life.
  • NANOcontrol
    NANOcontrol Registered Users Posts: 260 ✭✭✭
    That warning is at a pretty low voltage.  It is there not to protect the battery, but the inverter.  Many are set to turn off at 10.5V which just happens to be near the 10V required to drive the FET into saturation for lowest heating.  I believe people should be allowed to do what they want. If the inverter has an on/off switch (not a push button) one side of the switch is always 12V and the other side powers the inverter control electronics which is only about 200ma.  Just buy a small boost converter and set it to supply 13V (switch always off), Then you can drive the inverter down to about 8V if you want.. It is your decision.
  • Marc Kurth
    Marc Kurth Solar Expert Posts: 1,142 ✭✭✭✭
    That warning is at a pretty low voltage.  It is there not to protect the battery, but the inverter.  Many are set to turn off at 10.5V which just happens to be near the 10V required to drive the FET into saturation for lowest heating.  I believe people should be allowed to do what they want. If the inverter has an on/off switch (not a push button) one side of the switch is always 12V and the other side powers the inverter control electronics which is only about 200ma.  Just buy a small boost converter and set it to supply 13V (switch always off), Then you can drive the inverter down to about 8V if you want.. It is your decision.
    Nifty theory, but a very poor idea in the real world. Consider that:
    -12v batteries are "dead" at 10.5V under load. At this point, you have removed all of the rated capacity. Going lower is akin to slamming your engine past redline on your tach and holding it there. Even true deep cycle batteries rated to go to "0%" will sustain damage.
    -A little 1200 watt inverter (for example) that draws 110 amps at 12v, will attempt to draw draw  over 160 amps at 8V with the same load. Sure, if that's what a person wants to do.....
    Marc

    I always have more questions than answers. That's the nature of life.
  • Estragon
    Estragon Registered Users Posts: 4,496 ✭✭✭✭✭
    ...and absent a lbco, the inverter would draw current on a decreasing voltage / increasing current curve until voltage is near zero, or current melts something.
    Off-grid.  
    Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
    Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
  • CrazyKGB
    CrazyKGB Registered Users Posts: 2
    Guys, its making same noise because it thinks it overheating. The fan was broken and I use "redneck fan" from another plug before I get one from aliexpress and put it in.