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Re: (ET) Recommendations for modern replacements for the electronics?

Disclosure:  I am a distributor for Soneil chargers (based in Canada).

David Roden wrote:
On 2 Jul 2008 at 12:57, Fred Walter wrote:

I'm looking for a battery pack charger, that will go into a maintenance
mode when the battery pack is fully charged (so I can leave it plugged
in all the time).

The simplest and cheapest is a used automatic 36 volt golf car charger. Lester Lestronic range chargers are highly regarded.

I have a lot of respect for the Lester chargers, I still own several from 30 years of building EVs, but none currently in use. They have some drawbacks.

Note whether the nameplate AC voltage is 115 or 120 volts. In a ferro-resonant charger it matters. If you get a 115-volt unit and your input voltage is 120 or higher, the Lester will overcharge batteries. The primary protection on the Lester is the mechanical timer. That's acceptable if your application is daily use (like the golf carts that are the primary market), but not necessarily so good if your application is less frequent use (e.g., weekly).

No charger should be left connected all the time, no matter what the manufacturer says. Pull the plug when the battery is charged. Battery maintainers usually do more harm than good. Self-discharge is not that high on golf car batteries and they can sit for a few months uncharged with no harm.

Leaving the charger plugged in may be the best option in some cases. Leaving the batteries uncharged for a few months may do no appreciable harm, but it does not leave them ready for use. I bought my first Soneil charger for my E12 because it could be left plugged in, while the GE charger in the tractor was perfectly good. The tractor was stored at my cottage, and in that application I could not wait for the tractor to charge when I arrived. It needed to be ready to go when I arrived. The Soneil 3610SRF accomplished that on an aged pack. The bonus was the additional time I got from the pack as it improved over the course of the year. This case is anecdotal, and I can't guarantee others will get the same results.

Most battery maintainers are trickle chargers, or as I call them, slow-cookers. They produce a fixed voltage or fixed current (less common) and just drive that onto the battery continuously. The smart chargers that actually monitor the battery voltage are a different beast.

I'd prefer one that will also try to desulphate batteries.

EVERY battery charger is a desultator. That's how a battery charges. The gadgets that mutter claims about "crystal resonance" are snake oil. If they work, it's because they charge the battery! A good charger, used similarly, would work just as well. Pay no attention to the man behind the curtain.
I have a welder's power outlet available to me for charging (220VAC) if
that would help speed up the charging process with a different charger.

A Lester charger will need a 240 volt, 20 amp receptacle.

Actually, I have not seen any Lester chargers for 36-volt output that will take a 230-240 volt, 60 Hz input. I can't find any on the current domestic price list.

I have had one 96-volt output Lester that could use 240 VAC input.

The least expensive 36-volt Lester I see on the list is $345. If I'm reading the price list correctly, the Lestronics are more expensive.

The 3610 and higher current models in the Soneil line have the ability to use either 120 or 240 volt AC input (selected by a switch) in the same unit. As Soneils are compact enough to be carried on-board the ETs, this dual input voltage capability might be handy on occasion.

What motor controllers people are recommending? I've seen mention of
Alltrax, but not the model that was being used. Where can one get the
best price for one? (Keeping in mind that I'm in Canada.)

The Alltrax is a DCX300-ET. It's not listed on their website. Call them for information.

Alltrax is located in Grants Pass, Oregon. They have a dealer locator on their website.

Any other recommendations when it comes to replacing or adding to the
electronics on my electric tractors?

1. DO IT! You won't regret the change. MUCH less hassle, in my experience. I have an Alltrax and I'm very pleased with it.

2. The Alltrax works well, but is really designed for the E15. I don't know how it will perform with other GE models; the motors are different. Also, the instructions (while fairly easy to follow) are aimed at an E15.

3. If you're reasonably handy with electronics, you might also consider a 4QD controller (from England). They're really designed for PM motors, but if the ET's motor's field is energized just before you apply armature power, it acts almost like a PM motor. 4QD make controllers with brake control output. You can use that to pull in a relay that will power the field. If I were converting another ET, I might try this just for fun.

I have had enough trouble with electronic controllers in on-road EVs (including DC Power Raptors) that I am quite content with the mechanicals in the ETs. The only electronic controller that has held up as well in my experience is a Cableform Pulsomatic from the mine locomotive industry.

Hope this helps.  Good luck!

David Roden - Akron, Ohio, USA

Disclosure:  I am a distributor for Soneil chargers (based in Canada).

Darryl McMahon
Save water and your money.  The Water Saver toilet fill diverter.