jonr ✭✭✭


Last Active
Solar Expert
  • Re: AGM Absorb voltage range and temp compensation

    I looked at a few AGMs and most were in the range 3-4mv per cell per C.  So without an actual number, maybe 18-24mV for 12V.

    One said 3.3mv for standby, 5.0mv for cycle use.
  • Re: Solar rookie seeks help with 15-amp miter saw

    If it has a universal motor, it should work to add a 15A dimmer.  This would allow a softer start and far less startup amps.
  • Re: Off grid electric cooking and opportunity loads

    90 watt compressor with COP=3 is 270W of cooling.
  • Re: charging battery bank with generator

    > what is the best way to wire my batteries for the most even charge

    However your clamp on ammeter (current in parallel batteries) and volt meter (series balance) shows is most balanced.  Start with the recommended layouts and adjust as needed.
  • Re: diesel co gen with PV assist..

    > engine will run 90 % of rated kw
    > diesel wont make any exhaust heat with light loads   

    I suggested 85% load - which isn't light.

    It is most efficient to run somewhere around (but not exactly) the rpm that provides peak engine torque.  Which requires running at much lower than the engine's peak output rpm.   And much lower than the engine's peak output.    About 2300 rpm on a Kubota 1005.  Lower rpm (like 1800) will have have slightly lower efficiency.  

    If a generator runs a Kubota 1005 at 1800 rpm (it's rated to 3000 or 3600 rpm) then it is running well below the engine's peak output rpm and at most, 52% of rated engine output.   This will be a rpm that produces low engine wear.  Keep the engine load reasonable (50+% is certainly enough) and there will be plenty of exhaust heat.

    If you actually meant that the 1800 rpm generator (not the engine) will run at 90% of rated output, then we agree.

    > If you need more heat burn some natural gas.

    I agree.  once you have enough to supply the electricity you need, just switch on your NG furnace.