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Re: (ET) HL-Controller vs The E-meter



OK, I misuderstood the problem a bit...

If you bypass the HL controller and just run a full charge cycle with the factory charger/timer, does the e-meter reset and show full?

It might be that if you turn the voltage set point on the HL controller up a little higher and give it a couple of days, it would get the batteries closer to full?

And if you have the RS-232 version of the e-meter and some spare time, you could hook it up to a computer and log the data from a charge cycle (48 hours?) with the HL controller, then we could graph the voltage & current over time and might be able to see what the thing really does.


oleoranch aaahawk com wrote:
Jim, your calculations are good on paper but in real life when I use the tractor starting with a Full battery I can run for about 2 hours. This brings the battery down to about 80% DOD. With the Landis controller in the charger, plugged in all day and night when I start using the tractor the next day I can only run for about 20 minuets before the tractor slows WAY down from weak batteries. The E Meter confirms this "Battery at 0%" condition. You are correct that the E Meter is difficult to program. It takes me several tried to get is set to the tractor. R. > I think that the E-meter and the Harry Landis Controller may be mutually
 >exclusive (I say never having tried it).
 >
 >The e-meter has a lot of great features but all the programmable
 >parameters can make it tricky to use. So bear with me for a longish
 >explanation...
 >
 >When the tractor is in use, the e-meter counts actual Amp-hours used
 >(although the % remaining 'fuel' gauge is corrected based on Puekert
 >number, but that is another story). So far, so good.
 >
 >When the tractor is charging, the e-meter shows *corrected* amp-hours
 >put back into the pack. This correction is based on the "Charging
 >Efficiency" (CEF) that the e-meter calculates based on past charge
 >cycles. For instance, if the CEF is 90% then when 10 actual amp-hours
 >are returned, the e-meter will show that 9 amp-hours have gone in. I
 >won't tell you how many years of using an e-meter it took for this
 >detail to penetrate my skull.
 >
 >The CEF is recalculated with each complete charge cycle. A complete
 >cycle (or "reset to zero") requires 5 conditions to be met:
 >1) At least 10% of the batteries capacity must be used (so very shallow
 >discharges don't count)
 >2) 100% of the KWhrs removed must be returned by the charger
 >3) The pack voltage must rise above the 'charge voltage' parameter (say
 >40 volts)
>4) The current must fall below the 'charge current' parameter (say 4.4 amps)
 >5) Conditions 3 & 4 must be met for ***at least 5 minutes***.
 >
 >With a standard battery charger, the charge cycle starts off with a high
 >current (say 20 amps) and the pack voltage starts slowly rising as the
 >battery charges. As the bulk of the charge gets done, the voltage rises
 >more quickly as the current falls quickly. If the charge parameters on
 >the e-meter are correctly set, the meter sees a complete cycle and is
 >happy. Out of the box, the e-meter starts with a CEF of 90% and then
 >updates this value each cycle as it learns about the particular battery
 >pack.
 >
 >If the charger keeps going after the e-meter sees it as full, positive
 >amp-hours are accumulated, but as soon as you start driving/mowing it
 >jumps back to zero and starts counting negative as it should.
 >
 >Now add a Landis controller to the charger. As I understand it, the
 >charger no longer runs continuously until done, but rather cycles on and
 >off. On an empty battery the off time is short, and becomes longer as
 >the battery reaches full charge. So now even when all the KWhrs have
 >been returned to the battery pack, the 5 conditions for a reset may not
 >be met - particularly #5 that requires the conditions to hold for at
 >least 5 minutes.
 >
 >The result may be that the e-meter never sees a "complete" charge
 >cycle, so it doesn't reset to zero properly and it doesn't recalculate
 >the CEF. Or worse yet it occasionally does see a reset after sitting on
 >the charger for days and ends up calculating a horrible charge 
efficiency.
 >
 >Some options to get the e-meter to reset to zero on complete cycles
 >might be:
 >
 >- Make sure the 'charged voltage' is below the final voltage of the
 >charger & HLC combo; make sure the battery capacity is set correctly
 >
 >- Increase the 'charged current' parameter from say 2% to 4% of the pack
 >capacity, so the charge current doesn't have to fall off as far
 >
 >- Change the time to meet the charged parameters from 5 minutes to 1
 >minute (F05)
 >
>- Manually set the CEF (F06) - "not recommended" per the instruction manual
 >
 >Could also set the e-meter to count KWHrs in/out, which are not
 >corrected in any way (F04) and use the human brain instead of the
 >e-meter brain to track things.
 >
 >I'll be curious to hear the results of any experiments.
 >
 >
 >oleoranch aaahawk com wrote:
 > >    I have several "Landis controllers" and I had one on a tractor
 > > with an E Meter.  The E Meter keeps track of all battery functions
 > > including ah out and back in.   With the Landis controller the
 > > charger was never able to replace all the ah I has used.  Even
 > > if I let the tractor sit plug in for 2 weeks. The Landis controller
 > > is fine for maintaining full batteries for long periods of sitting
 > > but will never fully recharge the batteries if you use the tractor
 > > on a regular basis.
 > > R.
 >
 >_________
 >Jim Coate
 >1992 Chevy S10
 >1970's Elec-Trak
 >http://www.eeevee.com <http://www.eeevee.com/>
 >
 >
 >
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 >Elec-trak mailing list
 >Elec-trak cosmos phy tufts edu
 >https://cosmos.phy.tufts.edu/mailman/listinfo/elec-trak
 >

    No trees were destroyed in the creation of this E Mail, however many
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--

_________
Jim Coate
1992 Chevy S10
1970's Elec-Trak
http://www.eeevee.com