KERS experiment

[Fluffykins]

Set off earlier in my 5, fresh off the charger and 100% battery.

I selected E mode and thought about KERS. Now, I know the 5 doesn't allow one to select KERS 3 until the battery has gone down a bit but all I know is that it's "around 95%"

Well, there was me, chugging across Norfolk on country lanes, with a battery at 100% and my curiousity piqued.

I tried KERS 3 at 100% battery and, as expected, no dice.

I kept an eye on the GOM readout and tried again at 99%. Got KERS 3!

Interestingly, the retardation at KERS 3 and 99% battery is noticeably less aggressive than at a battery with a significantly lower state of charge, but it's definitely there.

So there you are.

 

[thefunkystoat]

It seems to allow selection of kers 3 at different values depending on who knows what factors I have been able to get it at 99 some days and been frozen a out until 94 on others. I would say that the effect of kers 3 doesn’t really get close to the full effect until you drop under 80%.

 

[Kithmo]

On my ZS, KERS comes back on after 3 miles of driving from fully charged. Not checked it on SWMBO's 5 yet.

 

[BarryH]

On my ZS, KERS comes back on after 3 miles of driving from fully charged. Not checked it on SWMBO's 5 yet.

That's my experience to since the BMS update earlier this year. The up date in effect shifted the 100% Available to a lower voltage range so when fully charged to 100% usable there is more head room in the battery to accept charge from KERS. At the low end of the usable battery 0% or more realistically - - - Range the battery has been dischargers deeper. There are a number of advantages to this. Firstly the more predictable KERS 3. Secondly since most users are going to fully charge more often than fully empty the battery the battery SOC (State of Charge) will mostly be at a charge level more favourable to the battery chemistry and there by more beneficial to the longevity of the cells.

 

[Petriix]

So, if the ZS allows maximum regen when '100%' charged, could you end up with more than 100% if you started at the top of a hill and used regen on the way down?

 

[JohnB]

My car seems to live in the 60% - 75% charged range and I always switch to KERS 3 when I first start. (Anyone else do the 2 fingered twitch for KERS 3 and Eco in one go?). Even then with KERS 3 it can produce different levels of braking early in a journey.

Given that KERS can easily bang 40/50 amps in (16-20 Kw) and potentially double that, I expect it's the BMS deciding on battery temperature/condition that it won't allow too much in just yet.
On very high SOC the effect will be far more noticeable.

 

[Jomarkh]

There must be a name we can give the 'eco' 'kers3' double flick ?

 

[Dt99idr]

There must be a name we can give the 'eco' 'kers3' double flick ?

We should call it 'Correct' ?

 

[m4rmite]

There must be a name we can give the 'eco' 'kers3' double flick ?

The oap flick?

 

[Petriix]

I often go for sport if I'm turning right at the end of my road as it can be a bit tight he out into the traffic. Then KERS 2 is normally ideal for the approach to the roundabout. After that I'll switch back into normal, then it's KERS 3 if I'm head down the hill. From there I'll regularly change between the modes depending on my route. Always back into sport if I find myself at the front of the queue at the lights, that acceleration never gets boring.

 

[JohnB]

The oap flick?

The "Codgers Twist" ?

 

[Kithmo]

There must be a name we can give the 'eco' 'kers3' double flick ?

 

[Stuwit46]

The tight wad double flick? I used to ”flick the KERS” I can’t remember the last time I used it, I now just keep it on 2. Probably the whe range decreases in the autumn I’ll be more aware ?. One thing for sure, after 11k miles I still forget at the roundabout a mile away from home that setting off with 100% that I need to brake earlier ?

 

[Lovemyev]

When the ZS EV has had the Jan 15th BMS update, the Regen is more linear, even when the HV battery is SHOWING 100% charged.
The buffer at the top of the pack has been increased on the latest software.
This can clearly be felt because the strength of the Regen has definitely been made available from the “Get Go”.
I am a fan of “Same Mode Steve”.
Always use the default mode of Normal and Regen level 3.
Over 18 months of driving and covering 13,000 miles, I find my right foot ? has become “In Tune” with what the car is doing.
Personally I don’t see a big advantage of “Faffing” about with different settings.
Is I am in normal mode and want max power, then “Sport” mode can be accessed by flooring the “Go” pedal.
Feathering the pedal in normal mode gives a very similar affect as using ECO mode.
Each to his / her own I guess ?.

 

[Adee]

The tight wad double flick?

Yep I think we're getting there

 

[m4rmite]

The flux capacitor flick

 

[n8sail]

Does UK MG5 default to KERS 2 or 1 every start/stop cycle? Mine stays in KERS 3 through stop/start cycles, literally never change it unless girlfriend is driving as she's apparently not very skilled with the accelerator pedal and having to modulate the pedal freaks her out. This one does default to "Normal" mode every stop/start cycle.

At 100% SOC, KERS 3 remains enabled on mine, but of course it does basically nothing to slow the car until 92% SOC, very consistently. By 90%, KERS 3 seems to be functioning full-strength. My guess is that has more to do with the very consistent temperatures (HOT) that we have here.

 

[Adee]

Does UK MG5 default to KERS 2 or 1 every start/stop cycle? Mine stays in KERS 3 through stop/start cycles, literally never change it unless girlfriend is driving as she's apparently not very skilled with the accelerator pedal and having to modulate the pedal freaks her out. This one does default to "Normal" mode every stop/start cycle.

At 100% SOC, KERS 3 remains enabled on mine, but of course it does basically nothing to slow the car until 92% SOC, very consistently. By 90%, KERS 3 seems to be functioning full-strength. My guess is that has more to do with the very consistent temperatures (HOT) that we have here.

I think I'm right in saying that it defaults to KERS2 and definitely N mode at switch on. Strange that yours is different. It seems to me that the problem with everything being software/electonically controlled these days (compared to mechanical systems) is that the number of released variants is practically limitless. This sounds like it could be a good thing but I fear the opposite is true when it comes to fault-finding and solving issues.

I found regen braking works much as you have said relative to the battery charge level as you might expect. It tends to be a bit variable though, sometimes biting quite hard and other times leaving you a bit closer to the vehicle in front than you expected. Strangely, I think it's also less effective when the air-con is on.