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Does using regenerative braking use up any brake pads or what is the process in which this works?

If I was trying to decrease any chance of problems with the car given the warranty situation, would it be advisable not to use the regen braking?

Also, I have about 1 out of 25 times that I hit the paddle and it shows Hill 1 or 2 , but the car does not slow down or what it seems to do is not engage the regen braking. I assume this is software driven and so it is just failing?
 

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regen does not use up brake pads

if you have a high SOC (i.e 48mi) hill mode will not work as there is no place to put this energy.

I have never heard of any regen problems on the Karma, I think you are being overly cautious but to each their own.
 

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You also can't get any regenerative braking below about 10 mph (well, maybe a little at 9 mph :D). The friction brakes start blending in at that point with the brake pedal; but with Hill 1 or Hill 2 and no brake-pedal, you can notice a drop-off in the braking effect around that point. (And you can see it on the generate/accelerate meter.)
 

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Can I drive in Hill 2 all of the time? I usually do that, in stealth, and may be why my mpg is so good after 18 months but is it going to wear out anything faster?
 

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I always run in stealth with Hill 2 in place, I like the engine braking effect that it creates. Reminds me of driving my other sports cars that have a lot of engine braking capability.
 

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If you hit the paddle and it does nothing other than changing the graphic, then you have at least 49 battery miles left at that point, and there is no place to store the regen energy.
 

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I have the following question - car seems to be able to charge back to batteries up to 15 kW of energy (going downhill), however when charged by cable through charger, it maxes at 3kW. How is it possible to charge battery through regen braking at more than 3 kW? Or does battery only take 3kW and rest dissipates in heat?
 

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Your charging the battery though an on board charger which controls the the charge rate versus the regen function which bypasses the charging function
 

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I have the following question - car seems to be able to charge back to batteries up to 15 kW of energy (going downhill), however when charged by cable through charger, it maxes at 3kW. How is it possible to charge battery through regen braking at more than 3 kW? Or does battery only take 3kW and rest dissipates in heat?
The first .25G of deceleration is done through regen whether you take your foot off of the accelerator or step on the brake. Once you exceed that decel rate the friction brakes are engaged. I've seen over 90KW of regen while braking. The seamless blending of regen and friction braking is one of the coolest engineering features of the Karma IMHO.
 

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I've seen my regen braking up to 106kW. If I step on the brake real hard I see no regen because it is all hydraulic braking.
 

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Your charging the battery though an on board charger which controls the the charge rate versus the regen function which bypasses the charging function
The internal power management in the car is designed to carry a huge amount of power (up to 300 KW at full power to the traction motors) and transferring even 150 KW from motors back to the battery during regen braking is nowhere near its maximum capacity. The wiring between the external charger and the on-board charger however is typically limited to 6KW, of which the Karma can only use 3.3KW. This is one reason why it is desirable to be able to use the ICE to charge the battery while driving the car because the generator has a maximum theoretical output of 180KW and would be able to charge the battery much more quickly than the 3.3KW on-board charger from a charging station.
 

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The internal power management in the car is designed to carry a huge amount of power (up to 300 KW at full power to the traction motors) and transferring even 150 KW from motors back to the battery during regen braking is nowhere near its maximum capacity. The wiring between the external charger and the on-board charger however is typically limited to 6KW, of which the Karma can only use 3.3KW. This is one reason why it is desirable to be able to use the ICE to charge the battery while driving the car because the generator has a maximum theoretical output of 180KW and would be able to charge the battery much more quickly than the 3.3KW on-board charger from a charging station.
I should know better then to post a basic answer ;)
 

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I should know better then to post a basic answer ;)
LOL! Sorry for the nerd-out, but disabling the charging was the most unwelcome change from the road show cars to the production cars. I understand that it had positive NVH and emissions impact but charging the batteries on the run would be a very cool feature if it is ever reimplemented.
 

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LOL! Sorry for the nerd-out, but disabling the charging was the most unwelcome change from the road show cars to the production cars. I understand that it had positive NVH and emissions impact but charging the batteries on the run would be a very cool feature if it is ever reimplemented.
Oh I agree matter of fact I was talking to Lomax about that the other day . I was wondering if he had any of his old contacts from Fisker that might be able to bring that software back on line .
 

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That software in its previous state is pretty much unobtainium. Even if we managed to get ahold of it, I doubt it would play very nicely with all the current software. 8AVGMPG may correct me if I'm wrong here, but I also believe that software level was prone to coupler breaking, which none of you want, ever.
 

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That software in its previous state is pretty much unobtainium. Even if we managed to get ahold of it, I doubt it would play very nicely with all the current software. 8AVGMPG may correct me if I'm wrong here, but I also believe that software level was prone to coupler breaking, which none of you want, ever.
I don't think anyone wants to regress entirely back to that version. We just want the current software to provide an option for that specific feature. But given all that is going on, it's not really a top-priority item at the moment, at least as far as I am concerned.
 

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The internal power management in the car is designed to carry a huge amount of power (up to 300 KW at full power to the traction motors) and transferring even 150 KW from motors back to the battery during regen braking is nowhere near its maximum capacity. The wiring between the external charger and the on-board charger however is typically limited to 6KW, of which the Karma can only use 3.3KW. This is one reason why it is desirable to be able to use the ICE to charge the battery while driving the car because the generator has a maximum theoretical output of 180KW and would be able to charge the battery much more quickly than the 3.3KW on-board charger from a charging station.
300kW (150x2 TMs) is the peak output for ~10s and is more like 200kW (100/each) ~ 1 hour continuous for the traction motors. In regen it is much less than that but I don't remember the figure off hand.

The generator has a peak of 175kW/125kW continuous, but only if provided 400v and @ 5000rpm.

Because of the time bomb (coupler) Lormax mentioned the generator is limited to I think 104kW/3300rpm.

I don't think anyone wants to regress entirely back to that version. We just want the current software to provide an option for that specific feature. But given all that is going on, it's not really a top-priority item at the moment, at least as far as I am concerned.
The genset recharge was a nice feature but boy would you be pissed when you saw how much fuel it used to recharge that battery. Among other things, The ICE used is just not efficient enough to have that feature and still pass emissions. In fact I'm pretty sure that up until the BL510 release, Fisker was getting fined by CARB for every vehicle it sold because it still didn't meet its emissions requirements.
 

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300kW (150x2 TMs) is the peak output for ~10s and is more like 200kW (100/each) ~ 1 hour continuous for the traction motors. In regen it is much less than that but I don't remember the figure off hand.

The generator has a peak of 175kW/125kW continuous, but only if provided 400v and @ 5000rpm.

Because of the time bomb (coupler) Lormax mentioned the generator is limited to I think 104kW/3300rpm.



The genset recharge was a nice feature but boy would you be pissed when you saw how much fuel it used to recharge that battery. Among other things, The ICE used is just not efficient enough to have that feature and still pass emissions. In fact I'm pretty sure that up until the BL510 release, Fisker was getting fined by CARB for every vehicle it sold because it still didn't meet its emissions requirements.
What's the deal with the coupler? Is that what mates the ICE to the generator? Is this part known to fail after a certain number of hours of use?
 
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