On Sunday 15 April 2018 19:50:12 jeremy youngs wrote: > > In the midst of this, I would stay away from lead acid , you can > > find ev take out batteries reasonable on fleabay, I recommend nimh > > if you can find them as they require far less control than lipo . I > > have a xantrex 2 k modified sine inverter that works very well and > > has a 100 amp 3 stage charger that is top. I also have several > > surplussed apc backup uninterruptible power supplies that make nice > > clean power, I have several 3k and a few 5k supplies. 2k in solar > > with xantrex pwm charge control. I will upgrade to a Morningstar > > mppt in the future. I also have a Lister diesel I wish to use to > > drive a 555 jho alternator and regulated to 48 v . I have the stuff > > amassed and several components test but not installed, I try to > > gather a heap of parts then build. I will send a link to the Arduino > > based generator control if you are interested. > One of the things I learned about was the care and feeding of large car batteries while I was tx supervisor at one of the Nebraska ETV sites back in the 70's. When I walked in the door, there was a 335 cummalong spinning a 150kw alternator that could run the place at around half power until the tank ran dry. It had 2 large car batteries that were contactor switched to 24 volts to spin this cummalong up. But a year later those batteries were toast. On inspecting the standby charger, a 10 amp rated 12 volt charger, which had a 56 ohm 2 watt current limiter, I found with fresh batteries was boiling them dry in a couple weeks. Replaced the resistor with a 470 ohm, still gassing pretty bad, so I went up to 2200 ohms. Still some gassing. At 5600 ohms, the gassing was just about eliminated. 7 years later, I had tossed a couple big si diodes across the resistor to speed up the recovery on general principles, and had turned the voltage regulator down to keep it from boiling the batteries if it ran for and hour or more. Those batteries were then 6 years old, and spun it fast enough that it was caught and running on the 2nd cylinder to hit tdc from wherever it stopped, just exactly as if they were new batteries.
Since, I've played around with LA batteries enough to learn that each battery has its own ideal maintenance voltage, that can vary at least half a volt from the textbook. And treated right, can last the life of the vehicle or more. Back before they put the regulator in the alternator and potted it up, I made several solid state regulators that were the last (except for light bulbs) electrical component touched on that vehicle. Each one had thermal comp so it was hit on the recharge after starting, with as high as 17.4 volts when it was -25 out, but which by the time the engine compartment was up to temps, was down to a hair +- of 13 volts. I never had to add water, and it would turn an engine full of 50w cmo at 20 below as if that engine had atf in the pan. Just don't race it when its that cold as it takes 5 minutes or more to warm up that 50w cmo & get it moving. Forget and you'll hear con rods clattering to remind you. Now days of course we'd put 5w-20 in it and drop the hammer in 10 seconds. We've now motors that can go a million or more miles, but we've still stuck with a 3 or 4 year battery. Now you know who to blame. -- Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
