mike95490 ✭✭✭✭


Last Active
Solar Expert
  • Re: New build off-grid

    reconsider the cheap dorm fridge.  They are usually poorly made and not efficient,   The new, full size energy star fridges will consume less power then a dorm fridge (unless it's an energy star model
  • Re: How to size battery and panels to run my well pump.

    How about looking at a new pump?  Grunfos makes some solar pumps, run on a couple solar panels, and a fancy new variable speed pump, that needs no batteries ?

    40A locked rotor (start-up) @230V means the inverter has to supply 9,200watts and then there's going to be some power factor monkey business too.  Can't do that at 12V .

  • Re: How to size battery and panels to run my well pump.

    2 wire or 3 wire (capacitor in box above ground?) ?
    Extrapolating my experience, your pump should consume about 1,500W from the inverter, and need at least 5x that for starting
     What is your Locked Rotor Amps ?  Your batteries and inverter have to supply that for about 1 to 1.5 seconds, then drop down to 1500w

    40.5A x 230V = 9,315 watts for starting.  at least a 24V system and likely a 48v would work best,

  • Re: Rigid mounted generator engine

    My generator shed has a 12" slab that the engine is firmly bolted to.   If you can actually engineer a floating, vibration isolation mount, that would be great, but randomly trying motor and transmission mounts to see what works, will disappoint you.  My backup generator has a isolation mount, maintenance cycle calls for mount replacements every 500 hours.  At 3600 rpm it's stable, but shutdown and startup, it has oscillation nodes and flails wildly for a couple seconds as it spins through them.
  • Re: Midnite Classic 250 - Whining noise when running (?)

    The classic has 2 normal cooling fans and a 3rd "Turbo" fan that kicks in if the others are not enough,  Since you are overpaneled, I expect it to be running hot and needing the fans,
    They also use a switcher supply, which operates in the ultrasonic range, and you may be hearing that, or sub-harmonics.
    (You are not hearing RF, unless you have implants that allow for that.)