Understanding regen

I’m new to this forum and have searched the “regen” posts but I need a better understanding of how it works. I have a stock 2000 and I use it in the mountainous area of Bisbee, AZ at about 6000 ft above sea level. Obviously the brakes are marginal and I will upgrade the fronts to disks. However It looks like it has regen based on watching the battery level increase on long downgrades. So here are some questions: does regen work on coast or only while braking; is regen adjustable and if so it looks like it involves programming-how do I do that?; I also note that on certain decelerations I hear the contacter open and then close when I apply the accelerator–is that normal and why does that happen? Overall the Gem handles the grades quite well and my range seems acceptable with nearly new lead acid batteries. I do charge each individual battery with separate maintainers when I am gone for extended periods and only use the antiquated original charger after each trip knowing that it will not repeat charging cycles nor level the pack.

Early t1 and t2 controllers do not have a regen brake switch as do later models.
T1 uses the start switch on throttle pedal. Lifting foot will hold at base speed within limits of motor and controller settings.
I’m not sure of effects of pressing pedal, except that it will halt regen. Possibly going into plug mode.
Plug is motor braking without returning energy to battery.
@LithiumGods has real world knowledge of this.
Programming is simple with settings plainly marked in Sentry sw configuration files.
You only need a usb to properly communicate with either the T1 or T2 controller. (Not the same protocol)
Or a handheld programmer.
What are extended periods? Less than a year, charge batteries and disconnect one end of string. If batteries can’t hold charge for a year they are junk.
This is open for discussion. Many convoluted methods are described to save batteries, and it is certainly best to keep them full. Imho kiss.

Interesting. I never could get regen to do anything noticeable on my 02, maybe the hills were the missing component.

What type of batteries are they? That original charger was only designed for flooded lead acid batteries. It can charge AGM batteries, but it will undercharge them, gels, on the other hand, it will ruin. It will overcharge them and boil the gel which will eventually kill it.

Yes, regen only works over the base speed at zero throttle. Without hills its not going to happen.
I assume that turf mode is also considered base speed, so it can hold that speed downhill.
@next2pool try turf mode to see if helps control speed. If it does, a magic magnet would in theory let you adjust for, say another 5mph.

Well damn, that’s why. I reprgrammed turf for 23 MPH, with slower acceleration etc, basically, a battery saver, ECO mode.

Road was reprogrammed for 35MPH, no restrictions on acceleration, etc.

Most of the time the 02 was in turf mode. Now it makes sense. It never went fast enough to get regen on pedal lift. Road mode was something I typically only used on a couple roads here were merging was done higher speed.

Now I need to go check the '10. I set it for moderately aggressive regen on accelerator pedal lift. That cart gets driven in binary for the most part - accel pedal is either stomped or not touched, so I see pedal lift regen all the time, even living on a pancake. I thought the auto decel regen cut in/out speed was a factory programming, be great to get the cut in/out down to around 10mph.

Do you happen to remember what base speed was on eM1400s?

Thanks everyone for the quick replies. As far as battery charging, I have conventional flooded lead acid batteries and all of the advantages (few) and disadvantages. Based on past experience with marine 48 V systems and complex RV combinations I am convinced that charging individual modules is the way to go rather than full string charging in order to prevent string imbalance and optimize maintenance of each individual battery based on its condition.
Regardless of all that I am still trying to understand the regen protocol of the 2000 version. From what I can understand from the replies so far is that the 2000 does have regen on coast or overrun but not during braking–is that correct? Also, will I get more regen if I am in Turf mode going down a long hill? Can the 2000 regen level be adjusted and exactly how does that work–is there a programmer I need to buy? Thanks again everyone !

I forgot to ask about the contacter opening after extended coast or braking and then closing again as soon as I step on the accelerator–what is that all about?

I just read a tidbit (I think it was a controller doc) that if the battery was full and on an extended downhill run, the Controller may choose to open the MC to keep the battery from overcharging.

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Or it just may be on the timer. Which would be a mistake.

How does the timer work and is that adjustable or fixed?

I’d need to refresh my memory, on what the cube timer under the dash does. I think for the dc converter…
Long time since I’ve studied a pre 2005.
The other option is in the controller logic.

The timer under the dash (upgraded early cars) is for key off accessory shutdown.

I think the MContactor is timed in/out and driven by the Motor Controller.

The McContactor?
Mmm, I’m lovin’ it.

clarity on regen, Regen on a Gem starts when you lift your foot off the accelerator pedal. The factory setting is very low but you can add more. Maximum regen for me was way too much. Jerked the car hard slowing it down. There is more regen at higher speeds and and very little at slower speeds, under 10 mph it kicks off. Later Gems have a setting that will ad more regen if you apply the brake. Never tried using it. I remove all plug braking on mine. Plug braking is hard on the controller and motor.

Interested in how to reprogram my 2013 ES to 35 mph? I am in a small town in Florida “about a thousand people” with a large flee market. The main road through town is 35 Mph with a fair bit of truck traffic. I would like to run with traffic when on that road. Any help appreciated.

Easy @bandit1 . Just get a magic magnet from @inwo. It plugs in between your motor and your controller and makes your controller think it’s turning less RPMs than it is, so it will let you go faster.

The T2 was the last of the controllers that you could set the max speed in. Later ones, like yours, which is either a T4 or T5 don’t have this setting, so you just need some electron trickery that Dave can provide.

@bandit1 , you will have a t5 controller, look at the label and see if it says fsip on it, it there a date past 2013? if so MM may not work. take a picture of label and post.

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hi why will it not work on fsip t5 controller ?

It has been recently discovered on a few T5’s that have been back to FSIP for repair that they may have tweaked some of the programming in such a way that the MM has no affect on speed outcome.

A quick look and adjustment of the numbers may be also required.

some yes, some no. But a Reprogram can release all of its potential.