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

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?
I'd be willing to bet it does. I don't have an E-Meter on my E20, however I do have one on my Geo Prizm (300 volt system, AGM batteries, 6.6kw MagneCharger). Typically I end the charge up about .5 amps on the E-meter, and about 10% overcharge as measured by the Dolphin controller and the MagneCharger diagnostics.
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?
Yes, however then you would be overcharging the batteries all the time. You'd have to remember to go out every week to add water. At which point I would say just go out every week/month and turn the ole charger dial.
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.
Sure, but to be honest, people have been charging T105s since the beginning of time. The charge specifications are pretty straightforward: You have to charge the batteries to a certain level, then equalize them to a certain value.
I'm very aware of this since my Prizm has two strings that each have *25* batteries. These are very long strings, and since the batteries are AGM types (sealed) you can't add water to them. Ever. So if you undercharge the batteries they will fail early, and if you overcharge you will dry out the battery.
My charge algorythm is based on the Hawker specifications: Bulk charge the pack to 15 volts per battery, then take them up to 15.7 volts per pattery for 50 minutes. I have an array of ten temperature sensors and two gas sensors that will shut down if any battery gets over 100 degrees F, or if hydrogen is detected. The extra bit at 15.7 ensures an equalized pack (because the strings are so long), the cost is I might lose a bit of water each time.
For the Elec-trak, one can just charge at 15 volts all the way, with a timer to stop the charge after say 8-12 hours. One will lose some water at the end of the charge, but you can pop the tops and refill the batteries if needed. 

Chris






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/>
 >
 >
 >
 >_______________________________________________
 >Elec-trak mailing list
 >Elec-trak cosmos phy tufts edu
 >https://cosmos.phy.tufts.edu/mailman/listinfo/elec-trak
 >

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