30 October 2009

Dirty power problem?

OK, there is a new theory about the occasional problem getting the Mini E to start charging at 240 volts.  The symptom I have seen is that the car starts charging but then stops after a few seconds.  Once it starts and charges for more than 10 seconds then it was always good to get to 100% charge without intervention.  But a week ago I often had to restart charging several times to get it to keep going.  The 120 volt slow charger always worked.

Recently I have heard two reports of exactly this behavior when trying to charge from a generator.  (I need to go back and ask if this was at 120 or 240 volts.)  So maybe the AC Propulsion electronics are fussy about noise on the power line, or an imperfect sine wave from the power line, or maybe the two 120 volts legs that add up to 240 volts are not exactly the same magnitude?

Mini, is anyone looking into this?

I have not had trouble for a week now.  Then again, the static I was getting on the radio at home is gone too.  Maybe someone in the neighborhood was using some nasty power tools or a welder or something?

But this needs to be fixed before the production versions of electric cars come out next year.

25 October 2009

Brown out protection

We had a visit yesterday during the rain from Don (#364) who stopped by for a recharge. While we were eating diner, I noticed the lights dim for a second. This is not unusual during a lightning storm, but I went to peek at #364 and sure enough, the Clipper Creek box was doing its job and stopped charging for a minute. A few mintes later it restarted automatically. I had not witnessed this before.

This is a built in feature of the Clipper Creek box that goes beyond what the Society of Automotive Engineers require in specification J1772, which governs Electric Vehicle Service Equipment. The interface box (EVSE) detects brown out conditions (probably due to a lightning strike or someone hitting a power pole in the rain) and suspends charging for a random time, making it easier for the utilities to get power back up to specified voltages.

This is not a big deal yet, but when there are millions of electric cars on the road, this will be one of several Big Deals for power grid stability.

And you guys that are complaining about the empty space in the box (many on the Tesla forums) - the Clipper Creek box was designed back in the 1990s in the era of the EV1 from GM. Back then, the electronics to do all the safety functions took up all the room in that box. They redesigned the electronics onto a smaller board when this second wave of EV's started, but with the low volumes at present, it does not make sense to tool up a new casting for the enclosure when the old one works.

And I wonder if maybe the extra room in there might come in handy for the Vehicle to Grid functions that are coming, and other smart metering that can save us money as drivers? We'll see.

24 October 2009

Taking the freeway round trip for the first time

Winter is coming and although I love driving the back roads to work, the hills can be dangerous when it is snowing hard.

So for a couple days I took the freeway round trip to work to see if I can make it.  On Thursday I made it home with 10% left, but I hit all the lights and was at work (charging on the 120 volt cord) for maybe 9.5 hours.  Friday I left a bit early so I only charged 7.3 hours and I didn't hit all the lights.

Coming home on I78 into NJ from PA, the highest point is a couple miles before exit 12, around my midway point.  Knowing I had nearly 40 miles to go, I laughed when the miles remaining said 9.  It is down hill now.

Over the next ten miles the remaining range indicator went UP 10 miles as I knew it would.  I had never seen the "critically low" warning go off without charging from the wall box.  But out it went, with 19 miles remaining.  (By "critically low" I mean the warning that comes on below 10 miles remaining.)

Now I'm off the freeway.  The miles remaining gauge is not going up any more, but it is not going down much either.  For nearly another ten miles it almost holds steady.

At about ten miles from home, there is another minor peak in the Sourland Mountains, and my gauge hits zero.  I laugh again.  I know that there is about 10 miles left after zero although acceleration is limited.  But of course, the needle starts creeping back up as I regenerate my way down the other side of the Sourlands.  I got home at 3%.

Still, that is pretty tight but I know of at least 2 places of business that have let me plug in on the way home if I get in trouble.  And that 10 miles after zero is reassuring.

But I have not used the heater much in days.  We will see how long I can hold out as the weather gets colder.  

I'll talk about my secret weapon, a low tech portable auxiliary heater, in future post.  It costs only a few dollars, "recharges" in minutes, lasts for hours, but both driver and passenger need a separate one.  And you might call it Dorky.  

"Embrace your inner Dork, and let the Magic Begin!"

By the way, the shortest freeway route for me to work adds over ten miles versus the shortest back road route, but this route is still only about half on the freeway.  It ends up around 136 miles round trip and only saves 5 or 10 minutes.  I drive 55 (remember that?) and have not had much trouble from other driver since I stay in the right lane.

21 October 2009

Update on minor charging problem

I heard from #364 that he regularly has a problem starting the car after it has been off for only several minutes. The talk is that the battery pack goes into cell balancing mode or something for a few minutes if it thinks you are gone. Wait just a few minutes more and everything is fine. Can be a problem at times.

I noticed this once when I ran a short errand. The current theory is that the same thing can happen to the charging process. I usually take a few minutes when I get home and write down every number I can read out of the dash display, and some other things (see the link for "#458 Trip Log" at the right). So as the battery pack ages (I am at about 8500 miles now) the cell balancing happens more often. Two days now I have tried plugging in the charge cable as soon as I get out of the car, and both times it has charged all night. No problem.

This could be random, we will see in a few days.

Mini, any comments?

Any other drivers had these observations?

By the way, after some measurements and a talk with the good folks at Clipper Creek, I am certain there is nothing wrong with the wall box.

18 October 2009

Interior preheat

Several Mini E drivers have expressed range concerns due to colder weather in the North East and using the heater in the car. I have used an interior heater for years that I bought from Napa to preheat my cars so I don't idle them to warm them up, don't have to scrape the ice off, and don't freeze on the way to work while the antique combustion engine warmed up.

Now I use it to increase my range in the Mini E. Here is a link to something similar to what I have:

Kat's Automotive Interior Heater 120 Volts #37100 $64.45


My particular model might not be available anymore. It draws 6.75 amps, or about 825 watts, the rating is 900 watts as is the link above. I plug it in when I get up in the morning and by the time I am ready to leave the car can be pretty warm, usually over 80 degrees F. When the weather gets colder I will probably go back to using a timer to turn it on before I get up. Preheating the cabin lets me run without any heat for the first ten miles or so, and then use a lower setting than I would have.

I have added cabin temperature to my logs, as well as heater settings. The link is over to the right under "#458 trip log only". Sorry about the confusing layout of the spread sheet, I'll rearrange it someday. Recent entries are at the bottom, unlike these blogs.

Mini says they don't want accessories installed, so I have my heater sitting in a steel pan that is meant for baking bread. It holds the heater at a safe angle and allows it to be positioned such that it won't melt anything like seats or the dash board. There is a thermal cutoff switch and maybe another safety feature in mine, I hope the link I found is as well equipped but I don't know, it is just a suggestion. The instructions for mine explicitly say it should be screwed down in such and such a fashion, and I have put the required mounting in my GM car. Maybe can move it to the Mini, I'll have to check with the service guys for permission.

And don't underestimate the power of taking hot drinks on your drive to increase your battery range. Liquids are also good for your immune system during flu season. And you can often run the heater at a much lower setting.

The rain here lately has put a stop to using the recirculate button to reduce the heat setting. Others have observed this causes the windows to fog up. I doubt that using the AC and the heater would use less power than turning off the recirculate. That would be interesting to try to measure...

But I do have to make some more measurements on heater power consumption. If someone else doesn't post it first, I am going to park the Mini E in the cold with the heater on at maximum, windows partly open, and time how long it takes to draw the battery from 100% down to 30% or less. Probably at fan setting 2 to start, although I rarely have to use more than the lowest fan setting after preheating.

Was anyone besides me expecting Mini to have used a heat pump instead of a resistive heating element? Too bad, but maybe it is not practical yet.

15 October 2009

Maybe it is the wall box?

Mini E #458 came home from service today.  They said at first that maybe the charging problem was the wall box, but then they found a trouble code so they replaced the big brass colored box under the hood again, like they did a couple months ago.

Except this time we get it home and still have trouble getting it to start charging.  The charging light on the dash board blinks a couple times and then it stops.

So I suspect the contactors in the safety box on the wall have gotten crusty or something.  Turning the car down to 12 amps makes it keep charging.  Then after it has been blinking steadily for more than 12 times, it can be set back to 50 amps and it will keep going until it reaches 100%.

The portable 120 volt 12 amp charger was always a bit finicky, sometimes it would take a couple tries to get it to start charging.  For several weeks that is all we had.  When the big wall box came, at first would always start the car charging immediately and keep going.  Now it is the big wall box that is finicky.

Good to get all this ironed out before there are millions of electric cars on the road.  That is what us "pioneers" (as Mini calls us) are here for.

I heard that since contacts cannot be plated with cadmium or other nasty materials anymore, it is harder to make high current relays reliable.  Maybe I have an example.  But good relays can be made, the just cost more now, or have to sealed better, or whatever.

10 October 2009

I have continued to have trouble getting Mini E #458 to start charging from the 240 volt wall box when the battery is below 30%, which happens every work day. The small 120 volt portable charger always works, and after running it for a while I can switch to the 240 volt unit. So something is wrong and tomorrow the car goes in for a checkup.

Then something new a couple days back. My wife took the "spirit powered" Mini E to work so I could take her conventional "fire and brimstone" powered car in for service, since her dealer is near my work place. Her drive is one tenth of mine, which is as it should be. So she got home with over 80% charge remaining on the Mini E, and she still had trouble getting it to start charging. I turned the setting down to 12 amps with the 240 volt charging box and this time it kept charging, but that might be coincidence.

Often what happens is that it will start charging but then stops after the blinking charge lamp on the dash has blinked 6 times. Sometimes it will go for ten blinks and stop. But once it blinks for more than 12 times, it will keep going until the battery is at 100%.

Maybe my little experiment awhile back running the battery way down weakened some of the battery modules? We will know soon. The "flying doctors" at the dealer are good, I'm sure they will fix it pronto. And I'm sure the production electric vehicles to come will not have this issue. Which is why we are doing this, after all. For the future! (Can you tell we are having fun?)

Update:  I recently found several more blogs from other Mini E drivers (I hope I have them all linked on the right side now) and I read that several others have run the battery "below zero".  Nobody mentioned ill effects from it.  So I assume that my charging issue (which mysteriously disappeared for a few days) is unrelated.  Service appointment was postponed until tomorrow...

I drive the Mini E quite a lot, maybe too much. I have driven it about 8000 miles over 4 months. So it has started to feel like a normal car to me. And when I get in a conventional piston car again, I wonder how I ever was able to stand it. Sort of like when someone says "how did we live without mobile phones?" OK, it is silly but that is the feeling. Feelings can be silly.

Now my wife only drives the Mini E on the weekends, and she still marvels at how much more welcoming it is, and easy to drive. Yesterday she was searching for words, and said something to the effect that she feels she could do anything in this car, like drive across the corn field we were passing, since everything else is so effortless.

I was starting to wonder if I should check to see if there was something funny in her green tea until I realized that I had become accustomed to the luxury of electric drive, while she was still marveling at the difference from combustion drive.

BMW, listen up! You should investigate using electric drive EVEN WITHOUT much of a battery. Just put a generator on the engine and an electric motor on the wheels, with the smallest battery in between that you can get away with. It will sell on the basis of improved drivability alone. There is a market for this beyond the environmental nuts like us. And it will help obtain economies of scale in the electric drive train.

This is most notable off the interstate highways, and on hilly roads. Despite cruise control, a conventional car requires you to reach for the brake on downhill sections. Even with an automatic transmission, the shifting is always noticeable on hilly slower roads. Not so with electric drive. The marketing guys should use the word "effortless".

07 October 2009

Charge while eating?

I was at a restaurant recently when I was low on charge.  I noticed an outdoor outlet right next to an empty parking spot.  I went inside and asked if I could plug in, and as usual the answer was yes.

Except that this outlet was the exception, it was not working.

Reminds me of the old saw, "the spirit is willing but the flesh is weak".  Something like that.  Here is becomes "the management is willing but the maintenance is weak".  Ha ha.

I got home with 15 miles of range left.