Yesterday I inverted my Potbox (the little device that controls acceleration from the 'gas' pedal) and immediately noticed I was able to get more out of my EV. The cable now travels in a straight line to the Potbox and my hill climbing is much better. Even better too is that I now have an ammeter to gauge how much I'm asking from the controller and motor, so I can see which gear draws higher amps and thus can down/up shift to save on the power I'm drawing. It would be nice to know the motor rpms (so I could know when in fact I should shift to avoid redlining it) as hill climbing - like a gas vehicle- is better in a lower gear.
The lamentations I expressed a few days ago are less, though I still think an extra battery would help things out. Simply (but pricey) solution...
Jul 19, 2008
Jul 17, 2008
Homemade A/C system
Saw this at a local EV meeting (MAEAA) and while I'm not too concerned right now about sweating like crazy as I drive in this heat, when I'm teaching I don't really dig pit-sweat...Great instructables on it here
Good range so far, but controller overheating
So I had my first drive today to/from my new workplace. Thankfully the trip (w/ a small 2-mile side trip for lunch) only took me down to just below 50% DOD (that's depth of discharge). After some research the past few days, it seems the following things are good for your batteries:
1. It is best to charge around the 50% point, even though one can safely discharge down to 80%.
2. One should avoid opportunity charging (charging whenever you stop) as that will 'cycle' the batteries too often and lead to a shorter battery pack lifespan.
3. One should charge just after driving to avoid sulfation on the battery plates. Not really sure what that means other than the lead plates loosing the power to transfer energy due to build up of material (sulfur) on their surface.
4. Disconnect the pack after charging to de-energize it (this I need to read more on, but it makes some logical sense - the energy is not lost in heat or doesn't flow through the whole pack but becomes isolated and stored w/in each battery).
So, since my roundtrip commute is about 17 miles, my test today shows that if I gain some range here after a few more charges, I'll have guessed right that my pack is good for my range purposes - commuting to/from work while still being able to make small trips to the store, library, etc. Then, I'll charge in the afternoon/evening.
With performance though, it is another, and more depressing, story. I think my pack may be too small for the hills on Wornall road past 75th as my controller almost burned out on the way home. I think the main issue was that my controller was in the afternoon sun today (which it was above 90F today w/o any clouds) and so on the way home I again heard the 'going thermal' high pitched whine as I climbed a few hills. Also, I may have had a lurch happen in the vehicle at one point, but I'm not sure as I was taking my foot off the pedal everytime I heard the whine and coasting a lot when I could.
Not to mention, I'm spending too much time floored to get up hills as the pack get below 20%-30% DOD. Going to work it is ok, a bit hard up steep hills, esp if I hit any red lights and have to start up from a stop going uphill, but overall I had a fine ride going there. Coming home was a different story.
I'm going to try a light, breathable cover to go over the control board so as to avoid afternoon sun. I thought about a curtain, but...that's way overdetermined - an orange VW w/ curtains!?
I'm leaning towards getting another T1275 to make this a 108V system, so as to increase my power and decrease the amps I draw when climbing hills. Hopefully that may address stressing the controller, but I'm not sure, I'll need to look into it.
Driving only w/ gauges would help a lot. They should be here tomorrow or Friday. What I've been doing is constantly checking the pack w/ my multi-meter before/after every drive, as the voltage climbs a few hours after a drive and is much lower just after you stop driving. Also, I've been shifting a lot to insure I'm not going to burn out the motor or overstress the controller - but of course, the latter seems to be happening. 1st gear up to 15mph, 2nd up to 30mph, 3rd up to 40mph, 4th no more than 50mph. What I need to read up on is what gear to be in when climbing between 25-30mph.
The short of it is this: this car may be a bit heavy for a 96V system on a Curtis 1221C controller and an 8" Advanced DC motor. Probably I should have spent more $$ and gone w/ 120V pack, 1231C Controller, and a 9" motor. But, I didn't. So, I need to shed some weight, drive more strategically and conservatively, keep the car components cool by installing another fan on the controller, and making sure it stays out of the hot sun.
1. It is best to charge around the 50% point, even though one can safely discharge down to 80%.
2. One should avoid opportunity charging (charging whenever you stop) as that will 'cycle' the batteries too often and lead to a shorter battery pack lifespan.
3. One should charge just after driving to avoid sulfation on the battery plates. Not really sure what that means other than the lead plates loosing the power to transfer energy due to build up of material (sulfur) on their surface.
4. Disconnect the pack after charging to de-energize it (this I need to read more on, but it makes some logical sense - the energy is not lost in heat or doesn't flow through the whole pack but becomes isolated and stored w/in each battery).
So, since my roundtrip commute is about 17 miles, my test today shows that if I gain some range here after a few more charges, I'll have guessed right that my pack is good for my range purposes - commuting to/from work while still being able to make small trips to the store, library, etc. Then, I'll charge in the afternoon/evening.
With performance though, it is another, and more depressing, story. I think my pack may be too small for the hills on Wornall road past 75th as my controller almost burned out on the way home. I think the main issue was that my controller was in the afternoon sun today (which it was above 90F today w/o any clouds) and so on the way home I again heard the 'going thermal' high pitched whine as I climbed a few hills. Also, I may have had a lurch happen in the vehicle at one point, but I'm not sure as I was taking my foot off the pedal everytime I heard the whine and coasting a lot when I could.
Not to mention, I'm spending too much time floored to get up hills as the pack get below 20%-30% DOD. Going to work it is ok, a bit hard up steep hills, esp if I hit any red lights and have to start up from a stop going uphill, but overall I had a fine ride going there. Coming home was a different story.
I'm going to try a light, breathable cover to go over the control board so as to avoid afternoon sun. I thought about a curtain, but...that's way overdetermined - an orange VW w/ curtains!?
I'm leaning towards getting another T1275 to make this a 108V system, so as to increase my power and decrease the amps I draw when climbing hills. Hopefully that may address stressing the controller, but I'm not sure, I'll need to look into it.
Driving only w/ gauges would help a lot. They should be here tomorrow or Friday. What I've been doing is constantly checking the pack w/ my multi-meter before/after every drive, as the voltage climbs a few hours after a drive and is much lower just after you stop driving. Also, I've been shifting a lot to insure I'm not going to burn out the motor or overstress the controller - but of course, the latter seems to be happening. 1st gear up to 15mph, 2nd up to 30mph, 3rd up to 40mph, 4th no more than 50mph. What I need to read up on is what gear to be in when climbing between 25-30mph.
The short of it is this: this car may be a bit heavy for a 96V system on a Curtis 1221C controller and an 8" Advanced DC motor. Probably I should have spent more $$ and gone w/ 120V pack, 1231C Controller, and a 9" motor. But, I didn't. So, I need to shed some weight, drive more strategically and conservatively, keep the car components cool by installing another fan on the controller, and making sure it stays out of the hot sun.
Jul 15, 2008
The don't ask/don't tell policy
If they don't ask, is it deceptive not to tell? From reading forums, this seems to be the approach people take: if the insurance company does not ask if you've made modifications to the vehicle or what kind of motor you are running, don't confuse them by volunteering the information that you drive a self-converted electric vehicle.
Well, not sure if this is deception, rationalization, or just the ordinary way of dealing with bureaucracies, but a major insurance company (which we were already rejected by) insured my vehicle. So, I'm now almost legit - just a little more paperwork for registration. Inspection went w/o a glick, although the mechanic wanted to know what he should put for the emissions rating...
This morning I filled a few of the batteries w/ distilled water - after a full charge last night - and got about 15 miles on a charge while only 50% discharged. My first official test at range and discharge. Thankfully my pack is well balanced (only varied between 12.85V and 12.94V between the batteries after a full charge), though I am getting a bit nervous that the hills here are going to dramatically reduce my range and that I'll need an extra battery or two as a 96V system may not be enough over the winter.
Well, not sure if this is deception, rationalization, or just the ordinary way of dealing with bureaucracies, but a major insurance company (which we were already rejected by) insured my vehicle. So, I'm now almost legit - just a little more paperwork for registration. Inspection went w/o a glick, although the mechanic wanted to know what he should put for the emissions rating...
This morning I filled a few of the batteries w/ distilled water - after a full charge last night - and got about 15 miles on a charge while only 50% discharged. My first official test at range and discharge. Thankfully my pack is well balanced (only varied between 12.85V and 12.94V between the batteries after a full charge), though I am getting a bit nervous that the hills here are going to dramatically reduce my range and that I'll need an extra battery or two as a 96V system may not be enough over the winter.
Battle over EV insurance
We are currently trying to get this car insured, so it can be registered and inspected in the State of Missouri (aka street legal), and finding that insurance companies (Geico, Progressive [ironic], Liberty Mutual [doesn't that read 'together we are free?', State Farm, et al) are downright ignorant about insuring a vehicle that does not run on gasoline. I'm not speaking of the individual sales people (most were interested and delightfully shocked that this is possible), but the institutional rules they are constrained by.
I'll spare you the boring details, but I'm finding many suggest not telling the agent the car is electric-powered (and converted by me, not a certified mechanic), which I think is a bad idea as I don't want to get into an accident (esp. if it is my fault) and find out I'm paying for everything b/c the details weren't properly agreed to.
I can only imagine I'll find something but still, the what-if of not finding insurance makes me nervous.
I'll spare you the boring details, but I'm finding many suggest not telling the agent the car is electric-powered (and converted by me, not a certified mechanic), which I think is a bad idea as I don't want to get into an accident (esp. if it is my fault) and find out I'm paying for everything b/c the details weren't properly agreed to.
I can only imagine I'll find something but still, the what-if of not finding insurance makes me nervous.
Jul 11, 2008
A huge sigh of relief
I just climbed a relatively long incline and actually hit 45mph in 3rd gear doing so. Thanks to Tom and Bob at Vee Village (on 16th and Oak in KC) for all their knowledge and helpful work, I now not only have a re-built front braking system (complete w/ new calipers and hoses), but, to top it off, a stellar motor mount. Little did I know (another recurring theme here) that the torque of the motor was only being absorbed by the transaxles and the soft rubber 'mountpoint' of the transmission (not really load bearing or made to twist). Thus, I was not only loosing acceleration power due to my locked front calipers (creating serious wheel drag), but the full torque of the motor wasn't being utilized properly. Notice too Tom's great design in putting arms for strength from the back of the motor to the adapter plate mountpoint. These will double as a place to attach a water protection shield for the motor and control board. Needless to say, I now feel this car is roadworthy...well, almost - now I need to properly register it. Thanks again Vee Village!
Jul 6, 2008
Newsflash: Brake work improves range
So if I would have totally worked through a brake issue I ignored 4 years ago (b/c the pedal seemed stiff enough), and then re-ignored starting again in April, my initial range would have been dramatically different. Thankfully, I jacked up the front end and found out that they are rubbing quite a bit and slowing down the driving a lot. I'm breaking down and having someone look over the front brakes, calipers, and hoses since that is clearly where the problem is (from evidence of heating up wheels, noise, and severe brake pad wearing over 15-20 miles driven). I'm quite excited, as I think that what I took to be a battery/motor range issue is actually a mechanical issue.
This seems to be a pattern here - w/ my wiring issue, my range issue, my motor issue - simple solutions that I overlook in my haste to get this running....
This seems to be a pattern here - w/ my wiring issue, my range issue, my motor issue - simple solutions that I overlook in my haste to get this running....
Jul 4, 2008
Driving around
I'm thankfully noticing that my range is improving and the climbing of hills out here a bit more possible. Not that I've been unable to climb some (I never thought Kansas City, MO had hills), but I did find out that the classic high-pitched sound you hear when just pressing the accelerator should not be heard past 0-3mph. I heard it and was told that is the controller 'going thermal' (meaning almost overheating). Not good, so I've got to either shed some weight or drive more conservatively. The car needs some brake work done, so that is next. And the ratchet strap that is acting as a motor mount needs to be replaced w/ something more permanent. But overall, wow, what a fun ride. You can barely see it, but I put an oval "EV" sticker on the back of the car for identification. Already I've had some hilarious encounters w/ people wondering why they don't hear the classic VW engine noise or 'what's all those wires in the back?'.
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