KERS; how to or how not to use...

[ATILKURT]

I am waiting for my order to be delivered and I have been googling about the KERS.
My question is; what if I continuously change the KERS level when driving? Is it going to damage the system?
Let's say I am on level 1 and driving fast but I see a red light or roundabout coming, is it ok to move the level to 3 to get the benefit? Or do the opposite in an opposite situation?

And how responsive is the system? I mean does it immediately starts charging the battery or is there a lag like 4-5 seconds or more?

 

[N2STY]

I would say on the MG is more of a auto set up when you start it will be in 3 if you don't fill comfortable with it you can turn it down some people turn it down for motorways so when you lift and cost it don't slow car to much
It don't work on a full charged battery as there is nowhere for the energy to go

 

[Gadget Geek]

Hi there and welcome to the forum.
Regenerative braking does depend somewhat on your driving style and preferences. Some people like level 3 and one pedal driving, where the car brakes as you lift off the accelerator. In my Kona, I set the regen (KERS) to 0 before I set off. It is more efficient when driving on the flat to let the car coast along rather than slow it down with KERS and have to use more energy to accelerate again.

As for responsiveness, when the car slows down it is putting charge back into the battery (unless it is full).

I use the different levels to moderate the speed when travelling downhill. I have a little competition with myself when travelling down Cheddar Gorge; from top to bottom I can usually get 2 miles of range back. The best I've managed so far is 3 miles.

 

[MG273]

I am waiting for my order to be delivered and I have been googling about the KERS.
My question is; what if I continuously change the KERS level when driving? Is it going to damage the system?
Let's say I am on level 1 and driving fast but I see a red light or roundabout coming, is it ok to move the level to 3 to get the benefit? Or do the opposite in an opposite situation?

And how responsive is the system? I mean does it immediately starts charging the battery or is there a lag like 4-5 seconds or more?

Changing the level of KERS while driving will not damage anything, it just might get a little annoying to keep doing it.
Generally I would say use a higher level of KERS in more stop/start driving conditions like around town as you will be slowing to a stop much more often.
Use the minimal KERS level when motorway driving or in conditions where you expect to be able to coast for longer as this is more efficient way of reducing speed.
Don't forget the system will activate KERS anyway when you get on the brake and only use friction brakes if KERS cannot slow you down enough for the amount of brake pressure you are applying. The change in KERS level is only really applicable to the amount of deceleration you get when you come off the accelerator pedal. You can still modulate the amount of KERS you get even if you are on level 3 by lifting off the accelerator pedal less (not fully). Hope this helps.

 

[Dave]

Personally, I have always left regen on the maximum with the EVs I have owned. You just need to retrain your right foot.

 

[Kithmo]

You could always use the brake pedal to regenerate kinetic energy instead of flicking the switch back and forth.

 

[Deleted member 7171]

Still driving my e208 till my Trophy LR arrives....in the pug, if don't use regen (D mode) and I use the conventional foot brake the power meter shows charge going back to the battery and at a similar level as when in regen (B mode). I guess this stands to reason as the motor is still slowing down in D mode same as it does in B mode.

Can an owner of a facelift say whether the power meter shows any regen if conventional foot brake is used please?

Cheers

 

[Dave]

Still driving my e208 till my Trophy LR arrives....in the pug, if don't use regen (D mode) and I use the conventional foot brake the power meter shows charge going back to the battery and at a similar level as when in regen (B mode). I guess this stands to reason as the motor is still slowing down in D mode same as it does in B mode.

Can an owner of a facelift say whether the power meter shows any regen if conventional foot brake is used please?

Cheers

Yes, braking with the brake pedal does activate regen. Greater than 10% regen level while braking will put the brake lights on when using L3 and braking with the acceleration pedal.

 

[seye]

I am confused by things I read about regen and automatic cruise control (ACC).

If on a motorway and using ACC and you gain on a vehical in front, does the system just ease off and maybe use some regen if the car doesnt slow enough? I read the car may actually use the physical brakes which would not be ideal

I am quite a steady driver. In my other car I use cruise and can easily moderate the speed by nudging the cruise setting, effecively manually doing what I would expect ACC do do. Brakes are never used as I am only reducing speed grradually by a few MPH and good planning means no need for them. I would hope ACC does the same.

Also, what happens if having made a safe space another car decides they want it and pull into it, which happens all too often. Suddenly the gap shrinks. What does the car do to reduce speed? Kers or brakes?

I expect to rarely use any pedals on a motorway

Picking up my ZS EV SR Trophy before the end of the month

 

[Dave]

Excellent questions ;-)

 

[Gadget Geek]

Automatic Cruise Control uses the radar to maintain a preset distance from the vehicle in front. If that vehicle slows down gradually, ACC will reduce power to the drivetrain so your car slows down also. If the vehicle in front slows down quickly, KERS kicks in and the drivetrain acts like a dynamo to use EMF (electromotive force) to resist the rotation of the elctric motor, which in turn generates electricity which flows back into the battery. Sudden decelaration will cause a combination of KERS and brakes to slow your car which is all controlled by the software.

 

[Phil Hayward]

The MG ZS EV uses the friction brakes to slow down with ACC, look at the power meter while going down hill with the ACC on

 

[seye]

So KERS for gap control , friction for speed downhill?

I would still expect reduced power downhill first with brakes only as required Ie a steep hill. Does it do that?

In a way I am glad it's not a easy answer,even though it should be. Getting clarity on operation will be great. I couldn't find this detail in the manual

 

[Dave]

With ACC the MG ZS EV with always use the friction brakes to slow the car. Regen is not used when ACC or MG Pilot is active. If ACC and MG Pilot are off then regen is used to slow the car.

The LR MG5 uses Regen to slow the car when ACC or MG Pilot is active.

 

[Slipstream]

Personally, I have always left regen on the maximum with the EVs I have owned. You just need to retrain your right foot.

Same here don't see the need to keep changing.

 

[ATILKURT]

Quite confused here. As far as I know, told by the dealer, MG ZS EV doesn't have regenerative braking, I mean regen doesn't work when u press the brake pedal (here some told it does).
It seems we also do not know if the regen hits immediately or if there is a lag like 3/5 seconds which is pretty much the time you use to press the gas again in a running traffic...

 

[Dave]

Your dealer needs to go on a training course.

It does not matter if ACC and MG Pilot are off or on, initial braking with the brake pedal uses Regen. Note that touching the brake pedal will immediately turn off ACC and MG Pilot.

However, if you slam on the brake in an emergency then no Regen is used and the normal ABS system comes into action.

There is no delay in the Regen coming on.

You need to borrow a car to try it.

 

[Gadget Geek]

Page 191 of the user manual.

When the vehicle is in a braking, over-run or coasting
state, the energy regeneration function is activated, and
the motor converts part of the kinetic energy of the vehicle into electric energy, which is then stored in the high voltage battery pack.

 

[Dave]

Your dealer needs to go on a training course.

It does not matter if ACC and MG Pilot are off or on, initial braking with the brake pedal uses Regen. Note that touching the brake pedal will immediately turn off ACC and MG Pilot.

However, if you slam on the brake in an emergency then no Regen is used and the normal ABS system comes into action.

There is no delay in the Regen coming on.

Page 191 of the user manual.

When the vehicle is in a braking, over-run or coasting
state, the energy regeneration function is activated, and
the motor converts part of the kinetic energy of the vehicle into electric energy, which is then stored in the high voltage battery pack.

As long as ACC and MG Pilot are not active ;-). This is a FACT irrespective of what the manual states.

When I need range I don’t use ACC or MG Pilot because using either of those will disable regen.

In the LR MG5 regen still works when MG Pilot is active.

 

[Gadget Geek]

As long as ACC and MG Pilot are not active ;-). This is a FACT irrespective of what the manual states.

Isn't that what the manual is saying? If the car is braking, in over run or coasting, surely the ACC and MG Pilot will be off.