IS THIS NORMAL FOR A LEAF?

Ingineer said:

Unfortunately there is no diagnostic system on the 12v battery that will detect a shorted cell. I'm sure you'd find out pretty quickly when your Leaf refused to go ready though!

Both the A/C compressor and the eberspacher heater are run from the high-voltage. Only the climate control fan is 12v. BTW, the heater is a 6kW unit, so it can draw up to that, it's not limited to 4.5kW.

-Phil

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Its amazing how inefficient the heater output is compared to the A/C. It always seems to take a great deal of time and power to get decent heat. Yet I always seem to be amazed at how little power the A/C is taking while blowing amazingly cold air. I would assume a regular ICE compressor takes more equivalent power from the engine that 250 watts or so.

Compressor operation is relatively efficient, even on an ICE vehicle.
That's why it is more efficient to leave the windows rolled up and run the AC, unless you are going very slowly, I think it is something like under 30 mph that AC operation versus ventilation are about the same.
See Mythbusters episode.
Unless you live in an area where you don't use heat very much, the resistance heating on the 2011 & 2012 LEAF, and also on the 2013 if you don't buy the heat pump system, is really a huge impact on vehicle range.
I have a 2011 and will continue to live with the resistance heating.
But in my opinion not having heat pump heating on an electric vehicle with a modest 21.5 kWh of usable capacity is a GROSS deficiency in 95% of the continental US.

ELROY said:

Its amazing how inefficient the heater output is compared to the A/C. It always seems to take a great deal of time and power to get decent heat. Yet I always seem to be amazed at how little power the A/C is taking while blowing amazingly cold air. I would assume a regular ICE compressor takes more equivalent power from the engine that 250 watts or so.

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The LEAF AC has an advantage over one in an ICE car in that it isn't working in a hot engine compartment. So the LEAF AC probably is a bit more efficient than the AC unit in an ICE car.

The use of a resistance heater, instead of a heat pump, in the 2011 and 2012 LEAF may have been due to the need to get the car to market rather than wait to get every last detail refined and optimized. Some late 2011s and all of the 2012s with the "Cold Weather Package" improved on it somewhat with the addition of the steering wheel and seat heaters. With the 2013 models Nissan has had time to introduce the more efficient heat pump. It is on ongoing process of improvement.

For me, the biggest failing of the early model resistance heater wasn't the fact that it is a big power drain but that there was no way to turn it off and use the CC system to blow air on the windshield to defog it. Since Nissan chose not to fix the problem with a firmware update, Ingineer came up with his own fix for the problem. The 2013 LEAF does, finally, have a "heater off" button.

ELROY said:

I was wondering what voltage the climate control system uses. On one hand, I'm sure its not 12volts powering a 4.5kw heater system. Yet on A/C, a 300 watt draw or so might only be about 25 amps or so. Does the heater actually use the battery pack high voltage with the orange wires? The a/c compressor doesn't have high voltage orange wires going to it correct? And I would assume the ventilation fan is 12volts? So perhaps the Climate Control system works on a combination of high and low voltages? Again, I would assume only the heater element would have to be high voltage.

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AFAIK, both the A/C compressor and resistive heater run on H/V. Although the compressor will often run down to 3-400 W once the car is cool, in extreme weather and/or when first cooling a hot car, the compressor will often run over 1KW. This is too large a load to run off of the 12V system.

DoxyLover said:

ELROY said:

I was wondering what voltage the climate control system uses. On one hand, I'm sure its not 12volts powering a 4.5kw heater system. Yet on A/C, a 300 watt draw or so might only be about 25 amps or so. Does the heater actually use the battery pack high voltage with the orange wires? The a/c compressor doesn't have high voltage orange wires going to it correct? And I would assume the ventilation fan is 12volts? So perhaps the Climate Control system works on a combination of high and low voltages? Again, I would assume only the heater element would have to be high voltage.

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AFAIK, both the A/C compressor and resistive heater run on H/V. Although the compressor will often run down to 3-400 W once the car is cool, in extreme weather and/or when first cooling a hot car, the compressor will often run over 1KW. This is too large a load to run off of the 12V system.

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Kind of scary...with all this high voltage running to various components besides the drivetrain...its just a matter of time before some pore technician gets electrocuted.

ELROY said:

Kind of scary...with all this high voltage running to various components besides the drivetrain...its just a matter of time before some poor technician gets electrocuted.

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I wouldn't worry too much about that; these cars are configured the same way hybrids are. The high voltage is only enabled when the car is booted up -- at all other times the battery is isolated by large relays so you only have voltage from the lead acid battery under the hood to worry about.. and as with any other vehicle that should be physically disconnected when working on the car.

The only exception to the above that I'm aware of would be during preconditioning of the LEAF, so you should treat an example in that state the same as you would one that was sitting in ready mode. In other words, not safe to work on because it is powered up.

ELROY said:

Kind of scary...with all this high voltage running to various components besides the drivetrain...its just a matter of time before some pore technician gets electrocuted.

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If a "technician" manages to electrocute himself, he isn't much of a technician. All the high-voltage is bright orange, and every single connector has an interlock that shuts down the power instantly. You'd pretty much have to cut into 2 high-voltage wires at the same time and do so without shorting the shielding. Almost impossible!

As soon as any shielding is cut and shorted to either high-voltage line, the car will detect the leakage and shut down. In the event of any crash big enough to set off the air-bags, it will also shut down.

-Phil

Ingineer said:

ELROY said:

Kind of scary...with all this high voltage running to various components besides the drivetrain...its just a matter of time before some pore technician gets electrocuted.

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If a "technician" manages to electrocute himself, he isn't much of a technician. All the high-voltage is bright orange, and every single connector has an interlock that shuts down the power instantly. You'd pretty much have to cut into 2 high-voltage wires at the same time and do so without shorting the shielding. Almost impossible!

As soon as any shielding is cut and shorted to either high-voltage line, the car will detect the leakage and shut down. In the event of any crash big enough to set off the air-bags, it will also shut down.

-Phil

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Good to know.
Kind of off subject, but if I replace the foglight bulbs with 25 watt LED units, will it trigger a bulb warning? I may possibly go with HID setup also, (prob around 35 watts each?).

I know my license plate bulb and front running light conversions to LEDs haven't caused any problem yet even though they consume less than 1/2 the wattage.

25 watts is pretty powerful for a LED unit. I wonder how bright they are.

http://www.ebay.com/itm/2x-H11-H8-CREE-SMD-Q5-High-Power-Projector-LED-Fog-Light-DRL-25W-HeadLight-White-/360575780798?pt=Motors_Car_Truck_Parts_Accessories&fits=Make%3ANissan%7CModel%3ALeaf&hash=item53f3fdc7be&vxp=mtr" onclick="window.open(this.href);return false;

ELROY said:

Kind of off subject, but if I replace the foglight bulbs with 25 watt LED units, will it trigger a bulb warning? I may possibly go with HID setup also, (prob around 35 watts each?).

I know my license plate bulb and front running light conversions to LEDs haven't caused any problem yet even though they consume less than 1/2 the wattage.

25 watts is pretty powerful for a LED unit. I wonder how bright they are.

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The OEM bulbs are 55 watts IIRC, so you should be ok at anything under that. The circuits are not supervised other than by the fuse which will blow if you overload the circuit.

Be warned that there is a lot of junk on Ebay. You may find that even though they are specifying 5X 5 watt LEDs, they may not be driving them at 5 watts. I bet they aren't, as the heatsink doesn't appear to be up to the task. Also, many of the Chinese LED retrofits don't use proper current regulation, and can fail in a short time.

-Phil

ELROY said:

Also, when sitting on my break listening to the radio I usually have it only on accessory position so no other gauges are lit up.

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As Ingineer pointed out, this is a BAD idea.
There is no good reason to leave the LEAF in ACC position.
If you are going to use 12V power for an extended period of time such as listening to the radio, you should always push the Start button twice to put in in ready mode, and then turn off the HVAC to minimize the high voltage potential power drains.
This is one of the big advantages of the LEAF versus an ICE.
With it in ready mode, the high voltage battery will keep the 12V battery charged.
As someone who has driven the voltage very low on the 12V battery in an ICE by listening to the radio for an extended period of time, and then had to jump start the ICE, that is not a problem in the LEAF. (Unless you're planning to listen to the radio for 25+ hours.)
Why would you just have the LEAF in ACC?
The LEAF does nothing to protect the 12V battery in ACC.
As reported in other posts, it doesn't do a very good job of protecting the 12V battery if you just leave it plugged in to the EVSE.
Leave it plugged into the EVSE while on a 5+ day trip, and you may find the 12V battery dead when you get home.
This is still a major software deficiency that Nissan has done NOTHING to correct.
With the current state of the LEAF software, it should be kept at a reasonable level of charge (>40%), NOT be plugged in, and if you're going to use the 12V, it should be in ready mode with the HVAC off.

mwalsh said:

ELROY said:

Not sure what GIDs are, or how to measure them, is there a thread on this?

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Gids are named after one of their discoverers, Gary Giddings, and are measured with a Gidometer, which he happens to sell build kits for. Use the trusty search engine and you'll find many threads related to Gids and Gidometers.

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Actually, I believe Turbo in AZ is the one that discovered the raw numbers, then gave garygid the info so he could make the meters. We need to change the name to TurboGids.

EVDRIVER said:

Accelerating quickly is not more efficient.

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It depends on what you do after accelerating. I can increase my m/kW h a lot by accelerating quickly, then coasting in N for a half mile.

LEAFfan said:

EVDRIVER said:

Accelerating quickly is not more efficient.

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It depends on what you do after accelerating. I can increase my m/kW h a lot by accelerating quickly, then coasting in N for a half mile.

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But you would be even MORE efficient if you accelerated slowly and then coasted.. The only way your average power consumption would be any better is if your average speed (and hence your associated drag) was low enough to offset the extra power required during your more rapid acceleration.

TLeaf said:

LEAFfan said:

EVDRIVER said:

Accelerating quickly is not more efficient.

Click to expand...

It depends on what you do after accelerating. I can increase my m/kW h a lot by accelerating quickly, then coasting in N for a half mile.

Click to expand...

But you would be even MORE efficient if you accelerated slowly and then coasted.. The only way your average power consumption would be any better is if your average speed (and hence your associated drag) was low enough to offset the extra power required during your more rapid acceleration.

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Nope, actually it isn't for shorter runs like a half mile. I've done it many times and I always gain more. Longer runs of at least a mile is where driving slow is much more efficient.

TLeaf said:

But you would be even MORE efficient if you accelerated slowly and then coasted.. The only way your average power consumption would be any better is if your average speed (and hence your associated drag) was low enough to offset the extra power required during your more rapid acceleration.

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Well, let me think about that. Certainly rapid acceleration uses extra power during the acceleration. But it uses that power for a shorter period of time. Leaving drag out of the equation for the moment, are you claiming that rapid acceleration will use more energy to reach a given speed than slow acceleration will?

If so, we need to explore why that should be true. From a thermodynamic viewpoint, that would imply additional heat generation. Higher amperages could heat the battery, wires, inverter, and motor more, so this is feasible. But assuming LEAFfan is not talking about flooring it, I would be surprised if the additional energy loss was above the rounding error compared to the energy used to actually accelerate the car.

If we can agree that rapid acceleration does not use significantly more energy, then think about the velocity curve for acceleration followed by coasting, plotted against time. Draw a line at any particular speed across that. The time spent above that line will be shorter if the acceleration is more rapid. Since this is true for any speed where you draw the line, it seems clear that the energy lost to drag will always be lower with rapid acceleration.

Ray

My latest test session was 58.5 miles with a 5.0 mile/kWh economy readout on the dash.
80 % Charge beginning
48PSI Tires.
48-65F Temps.

Mostly in town below 35mph.
About 16 miles of hwy driving 55mph at the end. (the Hwy driving didn't change my average from the 5.0)

Drove about 2 miles past the first LBW.
Took 3.85 hrs to charge. (L2 16A EVSE Upgrade)

I'm still a bit concerned that 5.0kWh driving only yielded about 56 miles till LBW.
100% charge conceivably would have only yielded about 11 more miles of driving.

So only 70 miles maybe at 100% charge to LBW.

You would think with any conceivable usable battery charge 21kwh x 5.0 m/kWh should at least yield 100 miles. I am no way near there. Even under very mild conditions.

Its almost as though I am getting pretty good economy, but the battery just doesn't hold that much? Specially considering the charging time was only 3.85 hrs.

Does this make sense?

ELROY said:

My latest test session was 58.5 miles with a 5.0 mile/kWh economy readout on the dash.
80 % Charge beginning
48PSI Tires.
48-65F Temps.

Mostly in town below 35mph.
About 16 miles of hwy driving 55mph at the end. (the Hwy driving didn't change my average from the 5.0)

Drove about 2 miles past the first LBW.
Took 3.85 hrs to charge. (L2 16A EVSE Upgrade)

I'm still a bit concerned that 5.0kWh driving only yielded about 56 miles till LBW.
100% charge conceivably would have only yielded about 11 more miles of driving.

So only 70 miles maybe at 100% charge to LBW.

You would think with any conceivable usable battery charge 21kwh x 5.0 m/kWh should at least yield 100 miles. I am no way near there. Even under very mild conditions.

Its almost as though I am getting pretty good economy, but the battery just doesn't hold that much? Specially considering the charging time was only 3.85 hrs.

Does this make sense?

Click to expand...

Great data set. 48F degrees on the battery would certainly account for a lot of loss (about 5%). But, 5% less than 21kWh is still about 20kWh, or 100 miles range at 5 miles/kWh.

You got about 70 mile range. Can you beg, borrow, buy or steal a Gidmeter? Where is your car (Phoenix?)?

TonyWilliams said:

ELROY said:

My latest test session was 58.5 miles with a 5.0 mile/kWh economy readout on the dash.
80 % Charge beginning
48PSI Tires.
48-65F Temps.

Mostly in town below 35mph.
About 16 miles of hwy driving 55mph at the end. (the Hwy driving didn't change my average from the 5.0)

Drove about 2 miles past the first LBW.
Took 3.85 hrs to charge. (L2 16A EVSE Upgrade)

I'm still a bit concerned that 5.0kWh driving only yielded about 56 miles till LBW.
100% charge conceivably would have only yielded about 11 more miles of driving.

So only 70 miles maybe at 100% charge to LBW.

You would think with any conceivable usable battery charge 21kwh x 5.0 m/kWh should at least yield 100 miles. I am no way near there. Even under very mild conditions.

Its almost as though I am getting pretty good economy, but the battery just doesn't hold that much? Specially considering the charging time was only 3.85 hrs.

Does this make sense?

Click to expand...

Great data set. 48F degrees on the battery would certainly account for a lot of loss (about 5%). But, 5% less than 21kWh is still about 20kWh, or 100 miles range at 5 miles/kWh.

You got about 70 mile range. Can you beg, borrow, buy or steal a Gidmeter? Where is your car (Phoenix?)?

Click to expand...

I'm in Southern California, Ventura County.
Car is barely of 3 months old.
Has never been quick charged or run to turtle.
I charged it last month to 100% for about 2 wks, so it should be balanced out okay.

Off Topic.
I was just driving around a Tesla Model S, P85 today.




Decided to take a video of an acceleration run with 3 people in the car total. Not bad for well over 5000lbs of running weight!
[youtube]http://www.youtube.com/watch?v=OSoWNbTKiNM[/youtube]

I have noticed some things with my range gauge which I'm not sure is normal. Today I hit LBW at 7 miles. Drove home and parked it with 4 miles remaining and 1 bar. I went out later and it still had 4 miles on the GOM. I only drove 1.9 miles miles and parked. Turned it on and next thing I know is I am getting the VLBW. 5 Batt temp bars, 50F ambient temps. Since I hit VLBW, I am going to charge it to 100% to see how long it is going to take. It says 7 hrs /23hr (120/240V). I suspect it will be significantly shorter than 7 hrs on my EVSE Upgrade + charger. Does anyone know how long it should take to charge from VLBW?

I was logging my trips on 80% charge, and it seems that it is hard to get much over 40 miles till I am on the last bar or so. Seem like 100 miles in everyday driving would have been wishful thinking, LOL.

Also, when I charge to 100%, it seems that it drops from 12bars to 10 bars very quickly, sometimes in only 5-7 miles. So compared to my chart below, the mileage increase from 80% to 100% charge will be barely a few miles more.

I am still wondering if there might be something wrong with my battery. It's just something I suspected from the day I picked up the car. (10/27/2012).

ELROY said:

I am still wondering if there might be something wrong with my battery. It's just something I suspected from the day I picked up the car.

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ELROY, the numbers you posted look perfectly reasonable. If you are still concerned about the battery, is there a chance that you could put a Gid meter to your LEAF? The recharge from VLBW to full should take somewhere between 6:45 and 7:00 hours. It's a hair over 7 hours from turtle to full on a new car, I believe.