does regen braking charge battery much?

[btyanke]

Just wondering does regen braking actually charge battery a noticable amount. The way i understand no chip in pds means all terrain mode and no braking. Am i right? With the small hills i will be going up and down would it be worth getting a hill chip to help charge batteries

[bigstik40]

I think the value of the regen. is mainly in the braking effect you would get, without applying brakes, while going down hills. The battery charging is a side benefit, and I suppose anything going back into your battery is better than nothing, but I don't think the amount going back into the batteries is significant, unless the hill is extremely long. Just my opinion - RAY

[Bowslayer]

I agree with the above post. Also, the Freedom chip is the one that removes the Regen braking, not the all terrain mode. I have run mine in every mode.... steep hill, freedom, and all terrain and to be honest I hated the regen braking. In steep hill mode it would throw me forward in the seat when I let off the accelerator.

[JohnnieB]

Here is a chart listing the four PDS modes along with the speeds and Regen Barking for each. (Source is Owner Manual)
And a chart showing the various J-2 configurations and the Beep-codes.

I run in either Mild Hill or Freedom. (Freedom "chip" with SPST switch in the jumper between Pins 2 & 3)

The Regen Braking in the Mild Hill mode is more like dragging an anchor chain rather than throwing out an anchor.

I don't know if the Regen Barking increases run-time much, but it does return a few amps the the battery pack.
When I finally get around to installing my 500A ammeter, I'll be able to quantify it a bit better.

[aleminx]

This is not true. My PDS in freedom mode catches me at around 18-19 and will not let me go faster than that no matter the hill. Voltage goes up accordingly depending on how hard is working to slow me down

[nickdalzell1]

All Freedom mode does on a PDS is give 19.5 MPH maximum and disables pedal up regen braking. It does NOT disable the regen limiting the maximum speed of the motor for that mode.

[CustomCurt]

it sure does save on brake parts, I have fun going full blast and hoping it stops me so i dont have to wear out my flip flop pushing the brake pedal

[JohnnieB]

Going back to the original question in this 8+ year old thread, yes regen braking does charge the battery, but how much depends on how long the regen braking is engaged and the amp flow during that time.

Now that I'm running an Alltrax XCT controller I can monitor and log battery voltage and battery amps, so I can see how many amps are being sent to the batteries and for how long it happens.

I've got my Max Regen Battery Amps limited to 90A and the max I see up to 96.8A when I lift my foot at about 25MPH and the Amps decreases down to just a couple of Amps as the cart slows. The longest duration I've seen on the data logs I've screened is about 15 seconds (probably on a hill), but most are 5 seconds or less.

On a 10 minute run in town (25MPH speed limit and a stop sign on every other block) regen braking returned about 40Wh to my 10,240Wh (42V - 245AH) battery pack.

Bottom line: Some energy is recovered, but not much. Maybe enough to offset what my LED lights use when I running at night.

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When possible, I use regen braking to slow cart to about 5MPH, or so, before using the mechanical brakes. The XCT adjusts field amps according to motor RPM during regen braking, so it is still effective at speeds under 8MPH.

[JohnnieB]

I screwed up.

The number of Wh (Watt-hours) returned to the battery pack is more or less meaningless. The meaningful information is the ratio of Wh used vs Wh returned during the trip, which is significant.

I also screwed up on the sampling rate, but that only changes the amounts, not the ratio of used vs returned.

With rare exceptions, there were 4 samples per second on the 10 minute log I calculated the Wh on. I multiplied Battery Amps times Battery voltage of each sample to get Watts and the divided by 14,400 (60/60/4) to get Wh.

A total of 294.54Wh used and a total of 29.78Wh returned, so on that trip 10.1% of the energy used was returned to the battery pack via regen braking.

I practical terms, that is akin to having 248AH batteries instead of 225AH batteries.

Of course, those numbers only apply to my specific cart, but I suspect the return for other carts is in roughly the same ballpark.