Re: (ET) Battery charger question

[Darryl McMahon <darryl econogics com>]

Disclosure:  I sell after-market inteliligent chargers, including models 
appropriate for the 36-volt electric tractors we discuss here.

I don't see the advantage of 12-volt bank chargers for 6-volt modules. 
To my mind, you're just creating 3 sets of unbalanced charging issues. 
In the series pairs, you can get out-of-balance charging, just as you 
can with a full-pack 36-volt charger.

Unless you are charging at the 6-volt module level, and you are 
monitoring individual module voltage, you aren't really going to be 
ahead.  And frankly, if you are monitoring module voltage regularly, you 
will get the benefit you are seeking (knowing there is an out-of-balance 
module - preferably within the warranty period), and can take action to 
address it (top-up with 6-volt charger as required or replace module).

Also, if your bank charger is a battery boiler type ('equalization' on 
every charge which is meant to act at the cell level), you are still 
going to cook your batteries to an early death anyway, and generate 
gases which will eventually eat the battery box paint and steel.

Suggestion:  if you are going to use a charger you are going to connect 
and disconnect frequently, do yourself a favour and put an ET accessory 
plug on it, and dis/connect that way.  I won't put in a charger on my 
own ETs without this now.

Put the effort into charging to make your batteries last and protect 
that investment.

Darryl McMahon

On 10/8/2021 11:13 AM, joeaverage frontiernet net wrote:
> Hello again. I've been wading through the archives for many evenings 
> now. Loving all the discussions about topics relevant to these tractors.
>
> The charger in my E15 works, even the timer works and I've used it a 
> bit. I acquired this E15 (and an E12S) just about six weeks ago and was 
> only able to mow with it once this season.
>
> I also have a little silver import 36V golf cart charger that I've wired 
> up to the accessory port. It is a slow charger - only 5 AMPS but I felt 
> I might have been able to rely on it to top off the batteries over the 
> off-season from time to time.
>
> Just pop the charger on the tractor for a few hours until the green 
> light comes on, and put the charger away until next time. Except - it 
> never actually switches off.
>
> A little research reveals many buyers with the same problem. So, I can't 
> trust it completely.
>
> I had noticed discussion about better chargers in the archives but 
> nobody discussed bank chargers much in the messages I've read so far.
>
> Is there any creative way to attach a 12v x3 bank charger to the ET so I 
> that I could park the tractor, flip some battery disconnect switches to 
> separate the battery pack into 12V pairs, and then fire up a bank charger?
>
> I have supposedly two year old Crown batteries that are clean and look 
> well kept. I want to make them last as long as possible. I did clean all 
> the connections, made sure all the batteries were full of water, and I 
> have a hydrometer.
>
> The ET charger seems to work well enough but its age does worry me a 
> little. Don't want to have it fail and ruin a load of batteries.
>
> Modern chargers seem to just no longer charge if they fail.
>
> Thanks,
>
> Chris in Tennessee
>
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--
Darryl McMahon
Freelance Project Manager (sustainable systems)