This week, we kind of sort of wrapped up the Mini Cooper Clubman and are now driving it. Which is quite fortunate in that it was 9 degrees Fahrenheit here this morning – a bit brisk. Cape Girardeau Missouri is blessed with four full 3 month long seasons and the spring and fall are truly a delight. Summer and winter less so. In July it’s 100 degrees F and often 80% humidity and we fat boys suffer terribly in the heat.
But the other end of all that is December. The days are so short it is dark by 4:30PM and it can get quite cold. Not Minnesota cold, but cold nonetheless.
We do love the little sports cars. And in the spring and the fall they are deadly weapons of romantic mayhem. But in July, and again in December/January, they are pretty much useless.
We found the Canadian EV heater assembly almost useless. It seemed like a good idea in July when we installed it and Randy Holmes of Canadian EV assured us that this single element heater would somehow be adequate because it was a “special voltage”. We never did get together on what that meant or how it could be adequate, but he IS in Canada after all.
Anyway, in December, it was a joke. The show this week was delayed until Monday, largely because I wound up with a 3 hour show. So we cut the heater section and a thing on the Roving Networks instrumentation and got it down to 2. I’ll try to include those sections this next week – or sometime.
In any event, and with any level of heat, the Speedster is a seasonal toy car. Bottom line, top line, whatever line, that’s the gig. It’s great in Spring and Fall, but air conditioning OR heating a small convertible like this is a losing battle however heroically approached.
The ultimate summer and winter car is of course the Cadillac Escalade EXT. And we do have plans to convert it, but his majesty Mr. Jim Husted has taken our project of twin eleven inch Netgains and made it a career move. We’ll get them someday. And I’m not going to disable the car until we do. We already have the transmission. But with new battery announcements just around the corner, and this thing requiring a massive 67kWh pack, we’ll do that with nextgen batteries.
That leaves the Mini Cooper. We have made some encouraging progress. I guess it’s always easier the second time around. We did revise our adapter to include the magnetic pulse pickup from the original engine, and now have a fully functional tachometer, and this has awakened our DME and more importantly, our power steering. Unfortunately, when the RPM falls below 600, after just five or six seconds the power steering kicks out. The ONLY place I need this electric power assist is in parking – typically when creeping along at about 40 rpm. So I have to put in the clutch and REV the motor to get the steering to kick in. ANd I have to do that every few seconds. But it does work.
And it IS nice to have the tach work. Far from a marginal dial in the corner of the car, this tachometer is quite large and centered on the steering wheel. I found it very annoying that it lay there dead.
I actually had some success getting working with the TIMS600 controller by stealing the encoder signal input to the controller. In trying to get it to “work better” I tried several different circuits, and finally loaded it to the point the controller lost encoder input and blew up an IGBT trying to run the motor with errant information.
We had no idea how to fix it, no support whatsoever from either the manufacturer or Metric Mind, where we bought it. Victor has never actually even run one of these controllers or motors for that matter. And the company is in Switzerland and has no interest in supporting it. I found we could order one from a European EV supplier and have it shipped to the states – 12 weeks later.
So we had seen Rinehart Motion Systems PM100DX become available on David Kois web site in a package with a Ford Siemens motor. This is a 100kW controller with a 300v and 600v versions available. And they are in Wilsonville Oregon – they speak English, and in theory might support their product.
They were not too keen on the project initially. We use an MES-DEA 200-250 motor. While not unheard of, it is expensive, and problematical. RMS support for motors is achieved rather by hand – they have to manually tune the parameters to the controller – somewhat by guess – and check the results on a dyno. So we had to ship them our motor. They had to MAKE an adapter for it to put it on the dyno. And while it does give them known support for another motor, how many 200-250’s are out there? Actually a few, but not many.
In any event, incredibly they had us a controller and returned our motor in a WEEK. Not bad. Actually, it was phenomenal in this business. I dont’ think we’ve ever gotten ANYTHING in a week.
In tearing down the system, we found some pretty serious damage to the off end mount, the clutch, and incredibly the shaft coupler. The coupler was actually TWISTED and discolored. This had been machined from a solid 4 inch round billet of 4045 hardened steel.
While we were fixing all that, Matthew Hauber thought little of our mid mount “belly band” and devised a much sturdier one of steel.
We built the car back up and installed the RMS 100kw unit.
I will NOT say the installation went smoothly or that this is a device for the novice. Just downloading and installing and configuring the sofware on a Windoze notebook was a bit of a challenge. The variables and indeed the thinking behind the Rinehart is a bit different from what we’ve done before. And it required some changes to the control wiring.
For example, we had to add a separate precharge relay. The Rinehart uses this relay to precharge the input capacitors through our 500 ohm 25 watt precharge resistor. Then, IT switches the contactor on. We had previously just run the contactor from switched 12v.
While a little more complicated, this is certainly a good system and I would rate it as vastly improved over what we were doing.
Kind of oddly, the unit wants a GROUND as a brake signal for when you put on the foot brake. On all cars I’m aware of, the brake switch puts out 12v. In our case, both the throttle voltage and the brake signal derive from the DME anyway, not from the actual brake switch. But it is of course a +12v signal when you apply the brakes.
I had to build a little box with a MOSFET and three resistors in it. Basically, the drain of the MOSFET is tied to +12v through a current limiting resistor. The junction of the resistor /MOSFET is provided as the output and with the MOSFET off this will be +12v.
The source of the MOSFET is tied to ground. The 12v brake signal is applied to the gate whenever the pedal is applied and causes the MOSFET to go into conduction. MOSFETS have very low forward resistance, and indeed this was an 80 amp MOSFET I had laying around that is also quite fast. Gross overkill, but it should last. When the MOSFET conducts, the output drops to ground. And the RMS appears to be satisfied with this arrangement.
The RMS has a software startup sequence we found a little peculiar. It has the usual FORWARD and REVERSE 12v inputs. But it REQUIRES both to be at ground during startup. It THEN requires a BRAKE signal and the appropriate FORWARD or REVERSE to appear simultaneously to complete its startup sequence.
i normally just wire FORWARD to 12v, leave REVERSE disconnected, and use the transmission to backup. The advantage being that I can cycle the controller while rolling down the road – occasionally a nice function if it trips out for some reason but can be reset to operation. I’ve done this with the Curtis 1238 and a Kelly controller quite successfully. It also worked with the TIMS600, but the DME has some requirements to do a cycle as well.
In any event, we wired a single pole double throw toggle switch (surprisingly rare to find). But if you switch into forward or reverse in the wrong order, or without the brake applied, it not only doesn’t respond But it seems you have to reset it and go through the sequence again. This is NOT natural or OK frankly. If you don’t actually “know” to do all this, you’ll never get the car going and I rate it a human factors faux pas.
It probably does have some salutatory safety merits, but not many.
We did notice that they had some unused digital inputs. And we requested that they do some software changes to let us use this with a switched ground input to disable all regenerative braking. We don’t actually have this feature on the Curtis 1238, but did have on the TIMS600. And I liked it. In inclement weather, I’m a little uneasy with regen. It is only applied to the front wheels, and you have less control of your braking, and are actually braking when you take your foot off the accelerator. On ice, this doesn’t sound like a good idea. I haven’t actually tried it yet, but it would seem even a little braking action on the front wheels on glare ice, performed by the not very active action of REMOVING your foot from the accelerator, is a disaster in the making.
They revised their software to include this feature. If you apply a ground to digital input 4 it will disable regen entirely. In the video, I noted that it only disabled accelerator regen, but I’ve already gotten a firmware update fixing it.
Along the way, we’ve had four or five phone calls, a dozen e-mails, and three firmware updates. Chris Brune is very calm, very professional, not at all in the “you guys are a bunch of idiots” camp I run into so often. Very helpful and very professional.
Is this controller ready for prime time? The fit and finish mechanically is just GORGEOUS. We’re driving the car and it makes not only good power, but it feels more “appropriate” to the Mini Cooper than what we had, which was probably overkill. We’re running 340 volts now at up to 300 amps and generally under 100kw, which is what this is rated for.
My take is that it is kind of in a prototype stage. This is four or five guys, struggling for life in a kind of hostile world, with a limited market. They build few. And so the pricing is very high, and very mercurial. The unit lists for an astronomical $9500. They sold us ours for $6500. And they allude to a deal with Remy that could get them into “production’ more in the $4500 mark. So I can’t make it out. I don’t know what it is or what it might be so it’s kind of hard to talk about value. I paid it gladly.
The configuration software is plain but quite well done. It will take a little getting used to and you do have to RTFM. But once accustomed to it, I like it. I found some of the variables a little bizarre and a little immature. We have GREAT configuration options on the accelerator, and almost NONE on the braking regen for example. But it is all software and as I said, we had three firmware upgrades in a month for this project. It will certainly get there.
On a broader front, I find the 650v AC solutions simply impractical for an EV. None of the peripheral items, DC-DC converters, water heaters, air conditioner compressors, etc can work at those voltages. While Rinehart has a 600v version of this controller, we found the 300v (up to 360v) perfect for this application.
So while it felt a little like we were on the beta team, and while I would admonish that “some assembly is required” and a complete novice probably does NOT want to use this controller. But that said, I’m kind of picturing a package with a Remy or other motor, with the whole gig somewhere this side of $10K, as being quite viable. The 100kw is PLENTY of power for a 3500-4000 lb vehicle if you have no NEDRA aspirations. Obviously in a sports car it WOULD be competitive. A Speedster with this in it would just be over the edge.
I think if these guys has a few installations of this controller and an appropriate motor out there to waive the flag publicly and work out a few of the software issues, it has a GREAT future.
A very interesting aside, and part of the reason I’m so impressed with this device, goes to our heat redux. We had a TREMENDOUS amount of heat from the TIMS600 and MES-DEA motor. It was incredible. We actually used the MINI radiator to cool it and found we had to turn on the radiator FAN to adequately cool it.
Same motor with the RMS PM100DX barely gets warm. Now it IS true we went from a 375v 400AMP system to a 340V 300 amp configuration. But the change in heat was dramatic. I’m guess that in addition to being 25% smaller, this controller is also much more efficient.
And that allowed us a very interesting experiment. We SHITCANNED the Mezzier pump and BUNCH of expensive Summit Racing hose work, along with a complicated fill and bleed procedure. We took the pump output of our 4kw heater, which comes from the heater core, and routed that through the controlller first, the motor second (both are liquid cooled) and thence back to the 4kw heater bottle which feeds the heater core.
This little loop is both interesting, and very unlikely to be effective. The heater core of course has a temperature drop, winter or summer, on or off. So it SEEMS adequate to cool the drive train – of course it does in December. We’ll SEE next July.
We rewired the pump to run whenever the ignition is on. But kept the heater elements on a manual switch.
So I can drive down the road and get a very modest amount of heat from the motor and controller – more on the highway of course. And if I need more, I can turn on the 4kw heater element.
Now this is a bit counter-intuitive. Our heater doesn’t work as well as it did. It is actually HEATING the controller and motor, and the loop is bigger with more coolant in it. So it takes longer to get up to temperature. But at 8F, we are still getting a pretty warm car I would say in five or seven minutes. Previously three minutes. It’s very nice after 10 minutes.
The heater is hard set at about 65C. Of course, there IS a pretty good temperature drop across the heater core. The Mini heater is quite efficient at extracting heat from this core. So I would guess the temps coming OUT of the heater core are a good 15C below that or 50C. With good flow, the RMS is rated at an inlet temperature up to 80C. The motor frankly doesn’t matter at these power levels. So with the heater on, and after running for a few minutes, I think we’re going IN to the heater core at 65C, coming out of heater core and into RMS at 50C, and coming out of RMS and MOTOR into heater back at about 60-65C.
This very unlikely system seems to work very well at this point. It remains to be seen if it can “hold water” in the summer.
Of course, in the summer we would never have the heater element on. But with the heater fan off (or diverter to A/C) we are not going to get as much temp drop across the heater core as well. I’m hoping for 10C. With a 40C ambient, (hot day) whether or not 10C cooling will keep the controller under 80C is a big question. I’m guessing at this point that it will. But we’ll just have to test it to find out.
If NOT, we’ll have to have a summer rig with a little heat exchanger that can be cut into the loop between the pump and the controller input. This is not a hard “get well” in any event – almost trivial.
So the good news is that the Mini Cooper drives well and that it heats/cools within parameters. And actually the heater, which you would not say “will run you out of here” it is comfortable on very cold days.
And unlike the Speedster, we have all the other creature comforts. Bluetooth phone, HEATED seat warmers, Sirius Satellite Radio, windshield washers, EFFECTIVE windshield wipers (actually I think we even have headlight washers and wipers) all the comforts of home and a modern automobile.
The Mini Cooper has been a much more complicated project than we bought into and a much more expensive one. We undoubtedly have $75K in this car at this point – but I think we did better than BMW on the expense side.
Rate Rinehart Motion Systems and the PM100DX a comer. And better, with Oregon based support in English, and in our case outstanding support at that. That’s a BIG issue as we’ve learned the hard way on the 2009 Mini Cooper Clubman Electric.