Tang Zhengping and John Allen – Brothers from Another Mother

This week we begin the more pleasurable work of installing pieces and wiring them up on the 2008 Cadillac Escalade EXT.  Some mounting issues.

We installed the two Soliton1 controllers at angles above the motors much after the fashion of the old Ford flathead V8.  This allows access to all the terminals and still access to the motor terminals underneath.  We mounted the Solitons on a piece of our aluminum aircraft decking honeycomb material, and by angle aluminum to the upper mounting bolt on each of the engine mounts.  This held well enough, but allowed a little wobble.

Brain installed some brackets to tie the decking to the rear Garret turbocharger fan and to the top bolt in the transmission adapter.  This left them rock solid.

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We also mounted a Vicor Megapac in place of the lead acid battery on the battery tray.  This unit features six 5v 40 ampere cards and two 15v 10 ampere cards.  We strapped these up to produce 15 v at up to 100 amperes.  It reads right at 15.05v unloaded and our systems in the Escalade should work very well at that voltage.

We mounted the throttle body inverted on top of the Megapac using a couple of pieces of bathroom plumbing.  It is inverted so that the butterfly valve, which is not entirely necessary, can clear.  I want to retain this as it gives me a good visual indication of what the ECU is doing with the throttle, and I can reach in and give it a twist myself for test purposes.

We added a diode to the input of this device.  I’m reasonably certain this was what was causing the Chennic DC-DC converter failures – back flushing the input caps into the batteries.  As one viewer pointed out, the Vicor already has a rectifier in it so the diode should be redundant.  That makes sense, but we’re still going to use the diode.  I don’t know exactly WHAT is in the Megapac, or in what order.  I know the power goes through a fan first, which seems to work from AC or DC indiscriminately.

We are going to buffer the throttle position signal with an LM1458 operational amplifier.  We bring out the ground and the 0-5v from the throttle body, tie them to the LM1458 along with our 15v supply.  The LM1458 can operate from +/-18v. And we bring the same ground out with the LM1458 output to the Soliton throttle inputs.

By tying the LM1458 output back to the inverting input, it becomes a voltage follower.  Whatever voltage we put in, we’ll get a pretty close approximation of that as an output.  So why do it?  The input to the opamp is on the order of 10 to the 12th power ohms in impedance.  It acts as a buffer to avoid loading the throttle position signal output to the ECU.

I get a lot of comments about the parallel motors and controllers.  We tested this a year ago and it’s just not a problem.  The two motors are on a single shaft.  The outputs do not precisely fight each other.  Rather like batteries in parallel.  That current would vary between the two is first not an issue, but the load existing equally along the shaft tends to even out the currents anyway, regardless of any discrepancy between the two controllers.  It just isn’t a problem.

Brian reinstalled the air condition compressor and power steering pump on the front adapter plate of the motor.  We have not installed the belt as we want to run some motor tests without aimlessly running the pumps.

We have put transmission fluid into the transmission and connected up the fluid cooler.  It will take a bit to work fluid into the empty torque converter.

Much work remains, but we are at the part where things start to move more quickly.  The heavy work of battery boxes and motor installation and mounting are behind us.  It’s now a matter of finding cunning places for contractors, disconnect switches, terminal bars, the heater, etc and hooking them up.  We also have to devise a liquid cooling system for the Solitons.  We already have this hanging on the test bench so most of it will just be moving it.
We’ll want to add a relay and use one of the Soliton outputs to run the pump only when cooling is called for by the Soliton itself.  A welcome feature in the more recent software releases.

John Allen continues his series on his Toyota rebuild.  I’m fascinated by this rebuild as John does not appear to be a master fabricator, and he is very value conscious as to his components.  His battery heater appears to work well despite all the warnings from the armchair builders, although I admit even I cringed when I saw all those resistive wires together in his junction box.  It appears it is a gentle heat.

John failed in this video, and on multiple fronts.  His controller blew up on him apparently, and his magic number on his motor adapter appears to have been off sufficiently that when he disengaged the clutch his flywheel gouged out a fairly impressive ravine in his motor adapter plate.

So why is he smiling so broadly.  Well, he just finished his first run in the SAME Toyota that used to have about a half ton of lead acid cells in it.  Only now it doesn’t.  The result doesn’t feel like an improved car.  It feels like a DIFFERENT car.  He’s going from zero to 80 mph in better fashion than the Toyota could with the ICE engine and he still has pedal left.  Instead of a ponderous climb, it is a delightful acceleration.  And you just never get over it.  But there is NOTHING like that first roll. Ergo the EV grin even WHILE facing some major rework.  Gotta love it.

This is what its about gentlemen.  For those of you watching and planning and hesitating, you don’t HAVE to be a master fabricator.  And the personal satisfaction of making a car GO on battery power from one of these conversions is just not something I can type yourself smart about.  You have to feel it.  It is gynormous.  It’s a head rush beyond what drugs can deliver.  ANd it lingers for days, weeks, even years.

It will cause you to rip that motor that you took weeks installing out in four hours just to get it fixed and back on the road.

And it is quite universal.  Our Chinese builder of the week, and faithful EVTV viewer Tang Zhengping invested the equivalent of $1600 in ducats in his 90 mile range creation.  For those who don’t speak Mandarin, what he is saying in the video is that he built a freakin electric car himself and he feels really really good when he drives it and f*** a bunch of oil companies.

It’s springtime and I’m driving around in the ivory Speedster Part Duh we did two years ago.  It’s not just that I can’t get over it.  Every stop at Lowes Hardware, the grocery store, anywhere involves an inevitable discussion with perfect strangers that are just bowled over by the car.  When they find out it’s electric, – cranial detonation right in front of you.  The front of their head just implodes.  We’ve gained enough notoriety locally that they are becoming much more aggressive.  “Your the guy with the electric cars…right?”

I am indeed the guy.

Stay with us.

Jack RIckard

http://EVTV.me

89 thoughts on “Tang Zhengping and John Allen – Brothers from Another Mother”

  1. Jack & Brian,

    You guys have got me revved up to do a conversion. If I can ever make up my mind of what to build, I am going to pounce on it….

    I know that whatever I build, I am going to have for a while and just can’t make up my mind….

    Short List:

    Ford Model A
    VW Karmann Ghia
    VW Thing
    Smart For Two
    Custom All Aluminum Car (Should be able to keep weight under 1200lb)

    I know I want to use the AC50 AC solution so I will need a fairly light weight car.

    My heart wants to go with the Custom Aluminum car (Built Some race cars in the past), but the state and “Clean Air Force” in GA make this almost impossible to register for street use. I have been trying to work with them on the red tape before I dump the time and money onto the car only to find out that I can’t drive it. This just seems to be a complete dead…

    Any car older than 1988 exempts the car and gets these DMV idiots out of the picture…

    Any comment from any of you guys would be welcome, especially if you have converted one of these cars…

    1. I like this Jack, “When they find out it’s electric, – cranial detonation right in front of you. The front of their head just implodes. We’ve gained enough notoriety locally that they are becoming much more aggressive.” That is exactly why I drive the electric purple beach buggy. With the motor hanging out back they even get the satisfaction of figuring it out them self.

    2. The trick to get around the DMV restrictions on custom vehicles is to build the vehicle with less than 4 wheels. They then classify as motorcycles, which have the simplest safety requirements, even in mass production.

      My personal favorite is the Bug-E reverse trike. Originally designed as a lead-sled, it can easily accommodate 90-100AH lifepo4 cells. Even at the original 55Wh/mi (you’ll likely do better than that with lithium) that’s about a 70 mile range with a 4.8KWh pack.

    3. Jeff:

      Friday evening I bought a 1974 baby shit yellow VW THING for $12,000. We’re arranging payment and shipment now.

      The THING appears to have a LOT of room up front for batteries, and a decent area behind the rear seats.

      It’s a standard VW motor and we are very familiar with this mounting for the AC-50 as it is identical to the Speedsters.

      It seats 4.

      Beyond that, it is a very basic vehicle, no CANBus or hard to deal with instrument panel. Lots of room on the panel for meters and gages. Simple car.

      It suits my sense of whimsey.

      I think this would be a great build to start out with. Once you have a grip on how much time it takes, how much time you have, and what’s possible, you will probably want to go on to bigger and better things. But I think a THING is a great confidence builder at a low cost. And probably a real head turner to boot.

      Jack Rickard

    4. So, you got the yellow one… It should make a good build.

      I like the VW Thing and agree that it has plenty of room for batteries. However, I might want something more weather proof that the Thing.

      All of the CANBus stuff does not bother me. I spent most of my life developing communications protocols and gateway devices.

      I’ll decide on a car in the next couple of weeks…

    5. Jeff, I just started a second conversion project with a VW based kit car, and I kind of wish I had started with that for my first. Parts are plentiful, available, and inexpensive relative to the Austin-Healey, and there is vastly more room and flexibility for all the batteries and other bits.

      Jack, a VW Thing is very funky and cool. I remember that color with some nostalgia(?) and why most of the Things in that shade had flower stickers all over them.

  2. Level 2 plus charging:
    I know it’s not the place for a beginner to make a suggestion to the EV standards and government officials but try this:

    We have J1772 75 amp components, serious AC power is much easier to come by than serious DC power, chargers can already tell if it’s 110 or 220 volt AC input. The proposed AC/DC connector is a monstrosity.

    Let’s just kick public charging points up to 480 volts and have chargers switch from 240 to 480 just like they do now between 120 and 240. 30 to 75 amps of 480 is a lot of power and I bet it would all work just fine with the J1772 hardware. Let’s hear it for 36,000 watt AC fast charging

  3. Jack,

    I’ve been thinking for the past couple of days about buffering the output side of my DC/DC converters with a 1 or 2 Farad cap. I had the radio up pretty loud a couple weeks ago and at a stoplight noticed the needle of my tach (now showing amps thanks to the Zeva 2) bouncing a little bit off the zero. I was really quite surprised seeing my Hi-Fi is nothing but mediocre stock. It got me thinking about the 12V load and what kind of stress if any it places on the DC/DC converters. It just seems to me that smoothing out the 12V DC power demand with a cap might be easier on the DC/DC converters and help improve their lifespan.

    There are plenty of 12V caps out there under $40 for audiophiles to buffer the output of their amplifiers. Do you think there is anything to be gained by installing one of these? In my case I’m using 2 400W Chennic-like converters whose reliability and longevity is completely unknown to me at this point.

    Thanks,
    Jon

    1. Good idea! Let’s stick ’em all on one board connected appropriately.

      Seb’s already done that for some lads with a VW Beetle.

      If its parts count reduction you are after then any reliability issues will be catastrophic.

  4. It seems a good idea to integrate the various black boxes into one. Just make sure you can get at the various sections to isolate, trouble shoot and fix; else the throw-away can be big bucks. I can’t help but notice even Jack has had a few of these during his battery experiments. However, failure equals knowledge!

    1. You might take a look at the Mean Well SD-1000H-12 DC-DC converter. It is US$300 from JameCo, 72-144vdc in, 11-15vdc, 60A out. It has a couple of interesting features; remote on/off, and 12V 0.25A auxiliary output. It has a 3 yr warranty, and lists a MTBF of 32k hours (3.65 yrs).

  5. I just looked up the LM1458 op-amp you plan to use for the throttle buffer. It won’t work well. According to the data sheet the closest the output will get to ground is 2 volts. You are wanting to generate an output voltage as low as .4 volts. In order to use the LM1458 you would have to provide a negative power supply voltage of at least 5 volts to keep the output linear.

    You need an op-amp with rail-to-rail outputs like the OPA2171. There may be a better one. I will admit there is a lot I don’t know about op-amps. I got bit in one of my projects by this phenomenon.

    1. The parameter is titled “Output Voltage Swing” It shows that if your LM 1458 is powered by a plus and minus 15 volt power source your output will only swing from plus 14 volts to minus 14 volts ideally. There is a minimum specification of plus to minus 12 volts. This leaves a gap of 1 to 3 volts between the supply rail and your output voltage. When you’re powering the IC with plus 12 volts and ground your ideal voltage will swing from 11 volts to 1 volt. It will never go all the way to ground.

      The OPA2171 is a quick and dirty search for op-amps with good output current, 12 volt power compatible, and rail-to-rail operation. Digi-key’s search function is excellent for weeding out undesirables. You can use many different op-amps in this application since the frequency response is not critical. Heck the good ole LM358 might work just fine.

  6. You don’t need a rail-to-rail op-amp, just one whose common mode input range includes Vee (aka Vss or ground). The venerable LM358 dual op-amp – which you can get at Radio Shack – will work fine. Don’t forget to put some bypass capacitors across the op-amp’s power supply pins.

    I explain why I recommend an inductor for protecting the capacitors in dc/dc converters, etc., in this post: http://www.diyelectriccar.com/forums/showpost.php?p=286892&postcount=187

    You are correct that a diode will block the troughs of the ripple waveform but it will still let through the peaks. Maybe it will work, maybe it won’t – far be it from me to dissuade anyone from determining the answer to that empirically.

    1. I read your explanation on DIY and I like it pretty well. The math works out and 100 uh would indeed be 5 ohms of reactance at 8 khz.

      I’m going to order some 14 amp 100 uh inductors. I think they were $13.61 on DigiKey. We’ll see if it helps.

  7. Jeff is absolutely right, you don’t need a full rail-to-rail op amp, just one which starts close to the bottom rail like a LM358. A TS912 should work as well, only Vcc max is listed as 18V, which is somewhat close to your supply voltage of 15V. The LM358 is good up to 32V.

    1. Not my field at all but am I missing something here?

      With the single rail op-amp, (if already made) Can’t you simply re-adjust the Soliton to the new output ranges?

      Perfection? A 12V DCDC isolating converter for -12V to make a +-12V supply.

      Would be good to know if I’m talking like a fool here.

    2. I had already tested the device on the bench. I get a slightly higher output than input which is puzzling, but not in degree. 6.54 in got me 6.64 out. Offset most likely. The zero was fina.

      We’ll be running 1.65 to about 4.75 in reality.

      As to ripple, the diode isn’t really about ripple. Mr. Jenkins is talking about the 12khz or whatever ripple. I’m talking about the one time shot of full acceleration and the 40 volt drop that is then held for six or eight seconds. This is what was blowing the fuses on the A/C controller on the mini. A diode fixed it. Could the same be happening with the DC-DC converters and it not be ripple at all?

      True enough, the Megapac has a bridge rectifier in it already, I’m sure. But the Chennics likely do not and I’m not exactly sure what or in what order the Megapac really has.

      The diode will have little impact on 12 khi ripple, other than to cut off half of it.

      Jack Rickard

    3. A 1/64th amplification and zero’s down ok. I bet you are gutted.

      That back EMF/ripple.
      It has to be a very good thing to keep leads short. If only to stop electromagnetically ripping drain covers out.

    4. I liked the rail to rail discussion so well, I ordered some new OPAMPS anyway.

      Kind of hard to keep things short. Cells in rear of vehicle, motor in front. For the long runs we are using Champlain’s shielded 4/0 cable and grounding one end of the shield to chassis.

      That should keep us from rattling manhole covers electomagnetically. But no effect on ripple. I actually do have something planned. Time and space being the deciding factors. Oh, and it weighs 125 lbs. That too. But it should have a decided dampening effect on ripple if that’s a thing we need to do.

      Jack Rickard

    5. 🙂 ok I say its for sure 🙂 Ultracaps in parallel with the batteries will take part of the load , and batteries are less stressed , I did some tests measuring currents in the battery and ultracaps.

      Less stress , more LiFe 🙂

      I have the data somewere in my computer, just have to find it
      regards

  8. This issue with John’s flywheel rubbing on the transmission adapter plate got me thinking about my own installation. The kit I purchased has a taperlock bushing and a coupler that goes over the taperlock and then the flywheel bolts to the coupler. I remember watching Brian assemble one of the flywheels to the motor in one of your cars a while back and I believe there was a spacer that went on the shaft between the motor bearing and the taperlock. This spacer was used to set the magic number but additionally it would transfer the force of the clutch to the motor bearing inner race instead of the motor shaft. In my kit there was no spacer ring so all the force of depressing the clutch will be applied to the motor shaft. If the force applied to the throwout bearing and then the pressure plate is not transfered to the motor bearing then all the force is applied to the motor shaft. If the shaft does not slip then all is well. However if the motor shaft slips in the bearing the shaft will move inside the motor and compress the wave washers on the comm end of the motor. It looks like in my WarP 9 this could move as much as 1/4 inch. If this happens the carefully seated brushes will no longer be and the back of the flywheel could touch the transmission adaptor plate. I wonder if this could be the situation with John’s setup. It doesn’t make sense that it used to work before he took it all apart and now touches when he depresses the clutch unless something like this is happening. Unless the motor shaft is sliding in the drive end bearing race or the taperlock sliped there shouldn’t be any way the flywheel could touch. It just shouldn’t be able to move.

    I hope that made some sense. I am now fabricating a spacer to properly position the flywheel instead of a trial fit and measure arrangement the kit maker gives in their instructions. This will also transfer the depressed clutch loads to the motor bearing instead of the shaft so the brushes will stay in their carefully seated position.

    If the motor shaft is moving then there is high probability of accelerated brush wear.

    I will be interested to hear in John’s next installment what the solution was.

    1. I’m always saying this about BMS’s. They overheat holding back a quarter of a Watt with a piddly little resistor while the machine is whacking in kilowatts of power.

      Then they wonder in amazement when the fires begin and there is a ready ignition source next to a battery with boiling electrolyte.

  9. Hi all,
    For those of you trying to package the A123 pouch cells Bill Dube, the owner of the KillaCycle, which is sponsored by A123, has some good information in this thread http://evdl.org/archive/.

    The thread starts on May 07 with a post by Christopher Zach. In this thread Bill spells out the packaging requirements to insure long life from the A123 20Ah pouch cell modules.

    1-The cells require constant compression. He says 300lbs across the face, or about 300lbs/50sq.” = 6psi.

    2-Tabs are best welded, but if using clamps they should be clean and use a thin coat of NoAlOx. Also he thinks that countersunk bolts in the clamps will give you less trouble with loosening. You need very low resistant connections to reduce temperature issues with high power draws.

    3-Because the pouch cells swell on each charge/discharge cycle and also as they age, you need to allow for this swelling. He says to put specially-made compliant” rubber” sheets between each cell and then strap everything between ridged end plates using steel banding.

    4-He says that pouch cells need this constant compression for a long life.

    5-If you are worried about temperature you should include aluminum plates. I wonder if heavy duty aluminum foil would work.

    I am not sure where you get the special rubber, but if a mfg. can’t supply compression info, I believe that you could test sample rubber sheets over a square inch area to get the right compression of about 6psi.

    Regards,

    Dad

    1. Interesting.
      I’m of the understanding cell expansion and contraction is purely from chemical structure, not gaseous. Jack will know if A123 batteries are compressed on the cells?

      Just Googled “thin rubber sheet”, inundated.

      It’s true about countersunk bolts.

      Not sure about No-alox during assembly if the contacts have to be perfectly clean. I’d apply afterwards as anti-oxygen protection on non-cell connectors?

    2. I do not believe the cells in the A123 module are under any particular “pressure”. The cells do NOT swell during normal charging and discharging. Like the Thundersky’s they DO swell if you over charge or over discharge.

      Naolox is not a bad idea. I don’t personally like it. We use Nordlock washers instead of countersunk bolts.

      Like most of EVDL, I don’t find this type of misinformation particularly useful.

      Jack Rickard

    3. Oh Jack,

      I am sorry that you feel the need to dismiss the message because you don’t like the messenger. I don’t know your history with the many folks on the EVDL, but to dismiss Mr. Dube’s instructions as to how the MFG says to build a module out of A123 pouch cells is like not changing the oil in you ICE vehicles at the MFGs recommended times. Neither are likely to result in much joy.

      I realize that you have the money to do as you like, but some of your viewers and readers of this BLOG may not have those assets. I assure you that Mr. Dube did not pull the packaging information out of thin air. After all, he is representing A123 on the race track. Surely you must realize that he has an inside track at A123 to get sponsorship. That relationship allows him access to much more info and product than you and I can possible get.

      I hope that you and others will consider exploring his packaging recommendations.

      Thank you for your time.

      Dad

    4. Dad:

      You need not feel sorry in the least, but you assume far too much not evident. I don’t have any like or dislike of the messenger at all, although your message is so garbled I don’t know if you are referring to Bill Dube or yourself. In any event, i don’t have any particular feelings, or familiarity, with either of you.

      I do dismiss Mr. Dube’s instructions and your fanboys appeal to authority means nothing here. If we can’t duplicate it, it didn’t happen. And if we have direct evidence to the contrary, it is true we become somewhat dismissive. We have destroyed dozens of these cells, and we know exactly when and to what extent and under what conditions they swell in even the least bit. And further, we have shown on camera the results when the swelling is “contained” or “compressed”.

      If part of it is demonstrably wrong, the entire advice must be looked askance.

      That he got it from the manufacturer is almost useless information. This company, in an almost comic series of missteps has culminated in a total recall of its entire output for the past year. We have one of THEIR supposed properly engineered modules on the bench now and it is in almost all respects a sorry mess. Had we designed it, it never would have made it on camera. It is fragile, easily damaged, difficult to repair, and simply not sufficiently robust mechanically for use in a car. You can dent it picking it up with your hands.

      So again, like much of what I’ve seen in these online forums, you have a supposed and self appointed expert issuing misinformation to an unsuspecting public. I do not approve of that. If he can demonstrate it, he should do so in the same spirit of inquiry. If he simply wants to assert it with your mimicked appeal to authority, I have no interest at all.

      If that offends you, I’m sorry. I would be different but I was this way when I showed up and it has served me pretty well thus far.

      Jack Rickard

  10. Jack,

    Your DC-DC converter output is 15 volts and 100 Amps. I made a film about the very nice Soliton1 (no posting here:) but crashed it in iMovie. I tested the 12 voltage input range and found out a 10,8 to 14,something volts was working fine. Over 14,something a saw an “over voltage error” and the Soliton was not switching on for a good reason. That was with software version 1.4

    Mathieu

    1. I’ve no idea about current needs on the Soliton 12V line or any issues I might create in this thought experiment but could you drop the input voltage with two diodes in series? They lose about 0.6V each.

      So 15v-(2×0.6v) = 13.8v

  11. Me again…

    I have not really a clue about diodes. I know what they do and really like the idea of a one way street from the pack to the DC-DC converter. For my feeling the converter is the weakest part in our conversions…
    I like the design of this Semikron diode to mount direktly on my possitiv copper terminal with a M6 thread.
    Will this one work..?
    http://www.produktinfo.conrad.com/datenblaetter/150000-174999/160849-da-01-en-Schottky_Diode_SKR2F50.pdf

    Thanks
    Mathieu

    1. Mathieu,
      I dream of the vehicle which runs off mains supply voltages.

      Imagine, we can recharge using nothing more than a bridge rectifier, maybe three phase to the AC regen. Use mains light bulbs, alarm horn, household electricals etc. to save pots of money and make things simple.

      Of course we cannot use ordinary car wiring and standard vehicle components or the chassis will become live. Mains Earth leak devices would be a very good thing on such a vehicle.

      Would feeding a battery pack with rough rectified AC represent state of charge as a varying load because of the Voltage difference? The UK seems to average 235V RMS so maybe 333V peak. We would need a 335 max Battery voltage just to be almost charge safe unless it splits into two half wave rectified packs charging at 165V.

      Scary stuff for brave people but if it works…….

    2. Oh sorry, filling up this blog again..
      I wouldn’t worry about a schottky diode.

      Just use a normal power diode of at least twice the maximum power rating. One with big holes each end to bolt tabs to.

      Avoid soldered wire connections on vehicles like the plague; adding vibration is trouble.

    3. Hi Matheiu,

      It’s a good diode but I’d not use a schottky diode because a fast switching speed in my book means noise.

      The thread on the screw is 6mm. this is where the heatsinking occurs.. Is this the right polarity for you?

      I would not consider the top post to take a bolt. If you do, it will be the first time I’ve seen it done on one of these.

    1. Hi Chad,
      The video I posted was in reference to my ironic humour about his advice.

      Good to know there’s a higher rate Moores law with EV’s over fuelled and it’s making people take notice. I’d guess its a damned sight cheaper to make and operate per run over fuelled too.

      Ok, well, OCC made it; not cheaper. But kudos. They really do need to extend the fairing forward to meet the fork legs.

    2. Chad you are never wrong?

      Absolutely! You mean un-enslaved. I’m a creditor. Thousands contribute to my tax free incomes and life is great.

      I’m not quoting Romney either.

  12. Jack,

    Regarding your supposed fix for the dc-dc converter– do you all have any simulation software you could use instead of trying different things to fix this as well as other problem you have?

    I intensely use Matlab for simulations. I would think it best if you used this software as well. It might be a money saver in the long run you know?

    1. What, and miss all this fun?

      It has been reveal years since I looked at Matlab. It was very subject then to garbage in/garbage out. We run into things all the time that come from unexpected sources – often that wouldn’t be included in the simulation. So they are very prone to WHAT you simulate, and we would generally always be simulating the wrong thing.

      An example. Let’s see. We had a instant error on the Netgain Warp Drive controller that occurred EVERY time we shut it DOWN at thte end of the drive. The error was stored, and so we couldn’t bring it UP without clearing the error. The error related to the 12v supply.

      As it turned out, we had two fans connected to the 12v bus that ran any time the ignition was on. But when we turned off the ignition, these fans continued to turn and actually turned into generators. This caused the 12v bus, even though power had been removed, to gradually “spin down” as the generators decelerated. The Netgain controller would note this as a low 12v input and throw an error before the voltage got low enough to shut down the controller.

      The cure turned out to be simply to use a relay to turn the fans on and off. When we shut down the bus, the fans still turned into generators, but the relay de-energized immediately so the output voltage did not appear on the main bus.

      You kind of have to know what is going on to adequately simulate it. And you have to adequately simulate it to know what’s going on.

      Useful tool. But I would spend hours playing with it, quite entertained, but still have the same problems.

      The AC controller on the Mini Cooper is a similar situation. Unless I duplicated all the components in the controller in the simulation, it wouldn’t show up.

      So no, we mostly plug stuff in and watch it blow up.

      This does not afford me the luxury of preening and posturing as a true “perpheshunal” engineer as most of our viewers and almost the entire online forum community so loves to do.

      But it’s a lot more fun, and it makes our cars run well.

      That said, some problems haunt us for months across multiple cars until we stumble on a solution. This is usually due to having difficulty getting the problem to show up reliably and predictably. If I can’t make it break on command, it is hard to debug it.

      Jack RIckard

    2. It is a very useful tool for engineers such as myself. And the fact which you are alluding to Jack is what we in the engineering world term as back emf– electromotive force. And all motors can actually function in this capacity, not just dc drives.

      But I do understand what you are saying, but I still believe this would be a useful tool to you. As you can do all types of crazy shit with it to emulate the anomolies of which you speak.

      And it is no longer junk in junk out. Whenever you implement it correctly you put stuff in and achieve real results. It is an invaluable tool in my opinion. And could save you megabucks in the long run in blown up stuff!

    3. Cory,

      Watch EVTV long enough and you’ll understand… Jack actually enjoys blowing stuff up. He enjoys performing destructive tests and sharing the wealth of information gained by it with his viewers. It’s kind of the point of the show. He does it so we don’t have to learn the hard way. Sure, he could do things virtually, but that takes the fun out of the whole experience.

      And trust me, if there’s anyone you’re likely to run into on a daily basis with first-hand experience with back emf, it’s Jack Rickard (and the Brain).

    4. I am well aware of this fact, just offering them some helpful suggestions. As well I am more or less offering to do the darn simulations for him because see I am totally disable at the age of 36.

      I just know there is a much better way to go about it and it pains me to see the suggestion of caps or inductors when you could figure it out in under 30 mins with Matlab!

    5. “It is no longer junk in junk out. Whenever you implement it correctly you put stuff in and achieve real results.”

      These appear to be contradictory statements. The term is garbage in/garbage out, not junk. It refers to the fact that if you do NOT implement it “correctly” that that the output is only as good as you put in. And my comments were about our inability to account for and input all the necessary variables to get an at all useful output.

      Jack Rickard

    6. Netgain cooling fan motor back EMF.. Reverse flow abatement, LPF filters and suitable fusing….

      GIGO filters!

      Maybe every fusebox should have one. There’s a nice business opportunity if someone cares to sell a little extra reliability?

  13. DGS, Jack: agreed.

    I have a question on Op Amps. I am setting some long term testing of cells and have plumbed in a Junsi Cell Log 8s to monitor voltage; but have now discovered a big difference in current in the monitoring wires (~30 microamps on some, over 200 in others). Over the course of a few months this will skew the tests. Could I use an Op Amp on each monitoring wire to level this out?

    1. Hi Andy

      Many thanks for taking the trouble to respond: I am though looking for something that will log voltages unattended. Apart from the Op Amp option triggered by the last show, I’ve considered a mess of resistors plus Arduino, or experimenting with I2C devices (which I’ve zero experience of)

  14. Yes Jack, but there are ways to simulate the results you are getting. I am sorry, but me and my friends would be able to run the simulation to simulate what you are experiencing rather easily.

    Yes, this requires quite the time knowing how to use both Matlab and Simulink properly. Anyway, if you ever want this done just let me know.

    By the way this DC-DC converter that is the root of this problem– what are the specifics on it. I am assuming you are using IGBT’s to step up your voltage no? Anyway I really need to know the specifics on this device before I could offer up any kind of ‘educated guess’ to what you are experiencing.

  15. Never mind my previous question, as I just watched your new video in which you explain the purpose of the dc-dc converter. So, you basically have a chopper circuit to provide you with +12 volts from what ever battery voltage you are running. This is necessary for you to do because of all the gizmos on the Cadillac runs at +12 volts. So now I understand both their necessity as well as their purpose.

    I would still like to know what the data sheet on these say. I have done a quick google search for them, but I need the part number of them if that is not too much to ask.

  16. Cory,
    Vicor bricks. 2*(3x5V).

    Jacks problems are non-straightforward common sense housekeeping issue. Nothing of any use on a pc.

    I once attempted to use one of those pc programs to draw up an infra-red PCM transiever for helmet to helmet use between motorcycles/helmets. It crashed on me every time I ran the simulation and it certainly did not instruct us on the issues of queer interference sources.

  17. Well I have used it extensively and it always worked very well for me. I am more or less certain that all of you detractors, Jack included, have not spent nearly enough time with them, otherwise you would be using them!

    And btw, I was doing simulations for lightning, etc, so do not try to tell me how it will not work for a random event!

  18. Rather the point Cory. I’m pleased you have found a tool you are obviously VERY VERY VERY HAPPY with. I wish the two of you a long and happy marriage.

    We are not that familiar with it. SO I guess we’re not REAL engineers like a very professional you.

    A video of me sitting at a computer doesn’t exactly liven the place up. And somehow we geek along anyway.

    If you have a piece of software that is NOT dependent on its input to produce an output, you can indeed tackle perpetual motion next. I’m just naturally skeptical.

    Software eats time in learning curve with payoff on the back end. At this point, I have to see a pretty clear payoff to start the journey.

    Final Cut Pro X has turned out to be worth the investment, I must say. BUt just barely… For awhile there it sure looked like a loser.

    Jack Rickard

  19. I feel you there Jack, as I too bought a copy of FinalCut which I have as of yet to use.

    I instead tend to rely on either Movie maker or Kdenlive for its ability to accept surround sound. It was the only thing I could find which accepted such audio 🙁

    And btw, I am sitting through an installation of Matlab just now, as I have never installed it on this computer yet.

  20. How about “flatten-em” power source for VW THING? I believe its ground clearance is high enought for these Ammo boxes which could enclose A123 pouch cells, on the vehicle’s belly.

    In order to prevent pouches and terminal tabs from moving within these all-weather-conditions tight containers, excellent thermal and electric insulator material EPDM rubber could be filled in, providing a serviceable system. These sell per kg.

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