Monday 30 December 2013

EMW 12Kw Charger is Working!

I just got my charger working for the first time, well an actual charge test anyhow.
Ran the test for around 16minutes, toroid got warm ~35-40Deg so it was definitely charging, it stayed in CC stage for 16 minutes before I unplugged, temp reported on screen was 12Deg, I am using an AC desk fan whilst testing, duty hovered around 25%, this was a 10A test charge. (rose to 26.5% in ~20 mins)
Second test at 16A in & out, all seems to be working even if the sensed voltage values are not correct, charged for around 20 minutes and took my single battery box up from around 76.4v up to 78.5v after disconnecting so it is definitely charging
Superb, now it is time to start my final assembly, I won’t be able to complete it until I have addressed the voltage sensing error issue but heck at least I can now charge my battery with my own charger 
My camera ran out of battery whilst doing these tests and I have stopped to charge and upload, I also tweaked the video settings as a test of a low res 640x480 video to see if I can read the screen’s (charger & DVM) if so I will use these settings as I would be able to record a whole charge cycle (I hope)

There is still quite a bit of finishing up to do on this charger before I can fit it into the car :-
Updates *** Done over Xmas period ***
1) Pot the caps (Update:- Done used electrical silicone)
2) Secure all the plugs, hot glue gun should do it, need to buy one (Update:- Done used electrical silicone as I already had it)
3) Hot Glue the Driver board to the power board, (can think of a better way at the moment) to avoid road vibration loosening boards. (Update:- Done used electrical silicone)
4) Drill some holes in my car for ventilation of charger, due to space issues I will probably fit the fans on the outside of the charger box.
5) Change output connections for an Anderson style connector (Update:- Done)
6) Rewire my charge connections in the car to accommodate a single charger connection, I currently use 2 separate chargers to charge with, kindly borrowed from Steve of Jozztek (Thanks Steve you are a life saver) (Update:- Done)
7) Wire up the J1772 Connector in the fuel filler cap to the charger (the charger will have to be in the car for this to be done)

Monday 11 November 2013

Charger repair begins

Sunday I was still feeling unwell but decided to try and pickup from where I left off about a month ago with my charger build, Solved the display refresh issue by downloading the latest firmware release (V11) after reading the last few entries on the diyelectricar charger thread last night, luckily this latest post included the TimerOne & LCD libraries, after downloading installing libraries compiling and flashing the display issue has vanished!

Horrah, I just hope when I get to the HV tests I don’t blow another IGBT/Driver/Isolator as this charger is starting to look expensive already.

However my envy of seeing other people using these chargers successfully should keep me going ;-)
Can’t wait to charge on the go, I am currently running my EV (for around a month now) to and from work via School for my daughter I do around 25 miles round trip and use approximately half of my 10kw traction pack, I only specified 40 mile range so currently it is all looking pretty good.


I am borrowing a couple of Zivan chargers from a friend who’s EV is off the road at the moment, charging takes me around 2 to 2 and a half hours total although I have to revisit half way through to switch off one charger as I am using one charger to charge two (paired) of my three battery boxes, the other to charge the third.

I hope to get my HV cut off boards (installed in the batt boxes) to control the charger so I can simply plug and go rather than timing everything.

Test1                                                       Test2
Calibration Sequence

New alloys & tyres for better grip in the wet and brake servicing

Came down with the flu on Wednesday and took a couple of days off work as I was coughing and contagious, so I did not get to touch the car for a couple of days.

On Saturday I was still feeling s#!t but managed to drag myself to the local tyre place and get some 195/50 R15’s on the new rims I had bought last weekend, whilst I was fitting them I serviced the whole braking system by removing the piston side of the callipers and freeing up the slightly seized rams(just needed a tweak with a pipe wrench to free up the ram) the car had been sitting for a year and so the grease had gotten stiff.

Tested the car with new wheels and tyres, feels great loads of grip, they do feel heavier though and this will probably affect my range, so I may get a couple of 185/40 R15’s for the front to avoid the slight rubbing on the plastic guard at full lock.

Still need to balance them may get the tracking done at the same time although it feels pretty good.

New 15” alloys for more grip in the wet!

After driving the Beat for 3 weeks it had become apparent after the first of the many winter rains to come that now that the EV has three times the torque it had as an ICE car it was severely lacking grip especially in the wet.

I nearly lost it one morning on the way to work after I put a little too much pressure on the pedal pulling out of a mini roundabout and had to correct some serious unintentional drift (That got my heart rate up!)

At that point I decided that it was time to invest in some wider alloys, a week of searching on eBay turned up some very nice reconditioned 15” 7” wide BBS style alloys for £250, I bought these and collected them from Burgess Hill at the weekend in the EV.

Unfortunately I was pushing my range limit (Still don't have the LVC cut off fitted! SHIT!) and I had not factored in the extra 30kg of alloy that I would be carrying so I ran out of juice about 20 meters from my front door, managed to coast it the last 20 meters with the car learching from an uneven power delivery.

Took me around 5 minutes to get the car in and on charge, I was rushing to get both chargers plugged in and charging ASAP as I understand from speaking with Steve that if I take the cells too low for even a few minutes I can kill them dead (as I did with the 12v LIFEPO last week! Which is now fugged).

I think I was very lucky on this occasion as all the cells seem to have recovered fine and I gave the whole car a good full charge to make sure, checking each cell on each series bank with my widget to make sure it all looked good.

I immediately went inside to start looking at getting the LVC wired & working.

My first EV breakdown!

Ok so even EV’s are prone to human stupidity! And I surprise myself at just how daft I can be sometimes, Last Thursday after leaving work I got back to a dead EV! A quick check and I spotted the culprit, I had left the sidelights on and drained the 12v LIFEPO flat, Damn!

Checked the Voltage it was way low < 2v.
“In my infinite stupidity” I thought that I may be able to use the 12V PSU to feed current from the good Traction Pack to the 12v block by defeating the contactor! (“WHAT ARE YOU MAD!”)

Yes I realise now that this was infinitely stupid thing to do as there is obviously a limit to the current the PSU can take after all its not a battery charger but a PSU, luckily I realised my mistake when the PSU turned into a nice electric heater for a couple of minutes and I disconnected it before I blew that up!

However whilst I was attempting to defeat the contactor using my battery cable, I inadvertently (in the dark) used the wrong +ve from the twin pack rather than the one from the single pack, which would be at 155v not 220v this promptly blew the 40A fuse I had on my battery connection lead and took out the contactor at the same time, SHIT! (I am guessing that current tried to flow back into the 3rd pack?)

After checking with Steve my friendly local EV expert it appears that my thinking was not entirely wrong here and Steve replied with
“Hmm the PSU SHOULD be able to charge the 12v pack OK – I’m guessing you mean that you shorted across the contactor so as to bring full input voltage to the PSU? I used to carry a real small 12v pack in the boot with a couple of croc clips – that way, if the 12v voltage dropped below the 9v required to operate the contactor I could touch the terminals with the little pack and supply enough power to close the contactor, at which point the PSU would kick in and recharge the 12v system.

However, this is only safe if the 12v pack doesn’t go below 8 or 9v.
That will be why the PSU started to creak then as I mentioned my 12v block was sat at less than 2v for several hours killing it dead me thinks, I have since tried to charge it but I think it has given up the ghost.

So I switched the 12v battery over to the lead acid that came with the car, same small size and it is quite a good Yuasa the original from the car so that should do for now, can't afford another LIFEPO at the mo.
After driving the car home on Friday lunchtime I felt sure the lead acid was working well and gave it a good charge to make sure.

So to summarise this week I have blown a 12V £100 LIFEPO due to leaving the lights on! I blew my 12v battery charger trying to recover said 12v LIFEPO £70, and I thought I had also blown my contactor  although after my long range test drive this weekend amazingly the contactor sprang back into life and is now working normally, following my stupid mistake last week when I blew a 40A fuse I have since swapped it for a 30A and charged successfully without blowing that fuse, so I will stick with 30A on that one.

Monday 28 October 2013

Vacuum assist here we come.

Ok so I promised myself that now the kids birthday parties are out of the way and I have been driving the car with decidedly dodgy brakes for 2 weeks it was time to fix the vacuum brake assist.

I had already had an explanation of what was require by Steve as he also needed a vacuum assist on his MX5 conversion.

I had also passed this on to my mechanic who had fitted the vacuum sensor and pump, however he had fitted the sensor in line with the pump and vacuum chamber and try how I did to get the vacuum to work it would either not seem to switch on an off correctly, it either ran constantly (blowing 1 £40 sensor due to my idiocy of not fitting an extra relay to separate the motors high current from the sensors relay contact, Dummy!) or not to run enough ie. No vacuum!

After a little thought (it helps) It became obvious that because the sensor is in between the pump and the chamber it would switch off before the chamber had reached its fully evacuated state.

The solution to this was to move the sensor from the T in the pipe to the chamber itself, in fact the best spot turned out to be obviously the furthest point from the motor and there was a convenient flat point on the chamber on the opposite side to the motor tube outlet.

Of course this meant breaking down the entire hydraulic master brake cylinder, disconnecting the brake pedal from the master  cylinder and removing the whole vacuum chamber, separating the master cylinder from the chamber and drilling and tapping a hole for the sensor to screw into, luckily I had a tap and die set that had just one imperial sized tap and die, 1/8 of an inch exactly what I needed.

So after breaking it all down and drilling and tapping on Saturday afternoon/evening I cleaned up the surface corrosion around where the master cylinder joined the vacuum chamber and rust treated it with some Jenolite I had kicking around  primed it with the part 2 Jenolite treatment and once this was dry around 10:30 Saturday evening, I finished it off by slapping some black enamel on it ready for Sunday’s reassembly.

Spent Sunday morning reassembling the whole shebang and testing it, worked a treat and now I have fully functioning vacuum brake assist, however this merely pointed out that the beat has s#!t brakes! :-(

So I guess I am now in the market for some new brake pads until I can get some 15” deep dish wheels (as recommended by Brad a work colleague who knows and likes his cars) according to Brad I have 14” x 5” wide wheels/tire’s on the rear and 13” x 4.5” wide wheels/tires on the front, he has recommended I get at least 8” & 9” wide wheels for the extra grip that I am now decidedly lacking.

Update on what is left to do

1) Get the Tax disc Done
2) Repair and get my 12Kw EMW charger working.
3) Fix speedo issue
4) Test brakes properly and fix if necessary Vacuum Assist Done, better brake pads needed!
5) Fit last battery box and test PSU/DC-DC converter. Done
6) Full test of all systems, lights, indicators, brakes, windows, anything that draws current from the 12V batt whilst the car is driving around the garden. Done, PSU works treat (Thanks Steve)
7) Assuming charger is working now, fit into Ali box and test again
8) Fit charger into car and wire J1772 (there are issues here that Valery and others are trying to resolve)
9) Wire J1772 plug through an adapter to my supply at home and test all systems work as expected.

Extending voltage sense cables

Spent Saturday morning extending the Voltage sense wires into the back parcel shelf of the interior, found some new speaker cable I had laying around cut each of the 6 wires on each of the 4 banks in each of the 2 boxes in the rear of the car (third one’s in the front) and soldered an extension in each wire cutting/soldering and shrinking each connection as I went after all these are live wires to the cells.

This all went swimmingly and after re-purposing an old racer tire inner tube for covering all the wires into a neat bundle threading and zip-tying each end I now have a neat easily accessible bundle of plugs that plug straight into my battery monitor widget, all tested fine after I had finished, Job well done (makes a change!)  

The first two weeks on the road

All looking good so far, still have the brakes to sort (get the vacuum assist working) and fuel gauge to fit along with cable extensions to make all the battery bank voltage test wires available from inside the car without the need to keep taking the soft-top rear part out (several screws) and removing the engine J motor bay service panels out to get to the bank sensor wires.

Each of my batt boxes has a circuit board for each series bank of 9 paralleled cell packs which breaks out the voltage sensory wires, in effect this means that I can sense the voltage on each individual cell string of 4 series banks in each box (12 banks in all to give me the 222v I need for the motor)

So when I plug my 20 quid battery voltage sensor widget it shows me 5 voltage readings, this is because I am using 5S cell packs, each cell pack having 5 actual cells in series, hence the 5S.

However as the voltage sensor boards are all connected in series across the box what I am actually sensing is the voltage of a single string of 4 cells, 1 for each series block.

So the first voltage reading on the widget reflects the voltage of cell 1 in block 1 + cell 1 in block 2 + cell 1 in block  3 + cell 1 in block 4, the second shows cell 2 in block 1 + cell 2 in block 2 etc.

This way I can at least tell if any of 1 string of 4 individual cells in that box is low it should show and if it does not recover after balancing (something I have not even got into yet, coming very soon) then I can remove that box for further investigation and once the box is open I know exactly which 4 cells to check individually to identify a bad cell and replace it if need be.

On the road at last :-)

Well it has been a very busy few weeks since my last post and things have really moved on.
As of Monday 14th October 2013 my EV is officially on the road (if not entirely finished!) as my charger is still awaiting parts (must chase these ASAP) Steve has been very helpful in lending me a couple of his Zivan chargers to get me on the road with my full 220V pack.
My partner had a serious car accident a week last Friday (4th) and wrote off our lovely VR4 Galant/Legnum twin turbo monster, I know I have been looking to replace this car as it eats petrol like I breathe air but this is not what I had in mind, thankfully my partner Mikki and my two daughters were fine other than Mikki sustaining an air bag blast wound, the car however is fugged :-(
Check the photo below!



Anyway I took the next week off work to give Mikki a break to recover and spend some time looking for alternative transport, however this also gave me a week to finish off the Honda Beat EV and get it on the road once and for all :-)

So Friday the 11th I took it for its first proper road test, I tested the "Beat" on a run to and from my work at Sussex Uni junction on the A27 this afternoon, in the rain, wipers going lights on for only half the journey (Bottled it!) ran the fans to clear the windscreen a little and "it were great", started out with 164.5v on the twin pack and 82.5v on the single, after getting back it was 152.2v on twin, 76.2v on single, I think that is approx. 22mile round trip (would need to check the clock, which I forgot to do today!)


Spent the weekend tweaking and charging to max safe voltage (84v per pack) after checking with Steve it seems my safe max voltage is 84v and LVC should be set at 70v this gives me a 14v range of “Fuel level” i.e. 84v on each pack means full pack 70v per pack means empty pack.

It is now Tuesday 15th and I have been driving the EV to work proper for a day and a half, so far so good, managed to get me to work drop my oldest  to school and do three circuits of Sussex Uni campus with friends to demo the car (they have been waiting a year for this)  after getting home I still had 76v per batt box, just under half empty.

The devil is in the detail

So near and yet so far, I spent a while tinkering with the brakes over the weekend as the vacuum switch did not seem to come on after the ignition was switched on, and now the vacuum sensor appears to have packed up, no apparent reason why but now it won’t switch on at all.
What with that and the blown IGBT DC-DC and IGBT driver chips on my charger, I am not having the best of times with the getting the car on the road.
However my partner is attempting to get the DVLA to give me a TAX disc today (we will see just how easy this wasn't tonight)

All in all it has been a little depressing this week with the failures, still I did manage to get the IGBT’s ordered they are not cheap at £69 each, bought two as I am intending to build another charger for the second EV which we have not started as yet.

Wednesday 25 September 2013

"Electrobeat" goes for its MOT at last and passes 1st time!

So Monday night I dropped the EV down to Brent for him to make up the 12v battery plate and fasten all the HV cables to the car properly rather than zip tied to the brake pipes.

Also asked if he could find me a 12v ignition source somewhere in the front of the car and run it to the brake vacuum pump control relay, and asked if he might be able to get some of the dashboard meters working.

I had noticed a few days earlier that there was an electrical connection in the gearbox and upon asking Brent he suggested it would be the speedo terminal, great I said can you connect that as well if you get time.

I was expecting the car back by the end of this week, however when I dropped in the following evening, Brent had finished the lot!

MOT passed and all the bits done (or so I thought) so I drove away with the thoughts of a free tax disc in my hand as the next stop, and promptly noticed the vacuum pump did not appear to be operating and the speedometer was having a hard time getting a stable reading ,the needle was jumping up and down like a cat on a hot tin plate!

So there are still a few issues to resolve before I can get this on the road:-

1) Get the Tax disc
2) Repair and get my 12Kw EMW charger working.
3) Fix speedo issue
4) Test brakes properly and fix if necessary
5) Fit last battery box and test PSU/DC-DC converter.
6) Full test of all systems, lights, indicators, brakes, windows, anything that draws current from the 12V batt whilst the car is driving around the garden.
7) Assuming charger is working now, fit into Ali box and test again
8) Fit charger into car and wire J1772 (there are issues here that Valery and others are trying to resolve)
9) Wire J1772 plug through an adapter to my supply at home and test all systems work as expected.

Monday 23 September 2013

EMW Charger testing the final chapter (I hope) (Update: NOT!)

I had already completed my low voltage (12v) tests and so far had discovered a reverse orientated IC blowing a 2n2222 and possibly the IC as well, replaced the IC and transistor and carried on testing with a lot of help and guidance form Valery I found a wrong value resistor out by a factor of 10 (27K instead of 2.7K that it should have been) replaced this and completed the low voltage tests with a fair amount of confidence that it was working as expected.

So I proceeded to HV testing and things were looking good, Connecting my 75v DC 45AH battery to the AC inputs went well, All measurements checked out fine.

Apart from the spark upon connection which scared the S#!t out of me (even though I was expecting it)
Moved on to the full AC test and this also went well (initially), Input voltage was around 288V (correct for 240Vac I think, RMS?) as shown on the LCD panel, Input current was set at 10A in and out as in the notes, Output voltage was still at zero as expected.

Started the charger and the dummy load lamps (2x60w incandescent bulbs in series) lit up as it entered the CV stage with an audible click then I got the duty screen, however when the values started to change the display problem (not clearing screen as values change) reared its ugly head again, I had been working around this with clrscreen statements.

As I could not see the readings without this being fixed I pulled the plug (Bad Idea?) and disconnected the load as in the instructions.

I need to fix the display refresh issue before I can move on.

When I plugged in AC power a second time the dummy load lit immediately!

And trying to repeat the test it responded differently, it just showed the Type 1 & 2 screens and then says charging complete without showing the duty screen, I tried disconnecting the dummy load and powering on this tripped my circuit breaker!

I then tried switching it back on (load connected again and it lit up again) and seeing if I could cancel the charge somehow, whilst going through the menus I heard a snap and saw a whiff of smoke, powered off immediately.

Smell check narrowed it down to the driver board I think (defiantly not control board) no obvious burn signs, so I guess it is back to low voltage testing again?

Low voltage test failed, now it won’t even power up, the only life I get is two flashing lights on Arduino red green in quick succession and nothing else LCD is blank. (Shit!)

Removed driver board quickly and checked over the board with my nose trying to identify which component had fried and my top lip revealed that U4 was red hot, so I am guessing this is fried and possibly the A3120 as well (Valery mentioned when these go they tend to go together)

SO I have 2 problems to solve now:-

Sort the display refresh issue so I can see the readings on the screen and repair the damage to U4 the DC-DC convertor that now seems to run very hot (I am guessing this is fugged) and probably replace the A3120 that is connected to U4, I may also need to remove and test the supporting components and replace as necessary.

Placed an order at Digikey for a replacement DC-DC (U4) and a few other bits for the next charger build, enough to get free delivery.
 
AC Input showing inrush resistors in series with live and neutral
 Output Diode package in white, Input Diode Bridge in black
 Driver board showing connections (removed from HV board for clarity of photo) 
 HV power stage board showing white inductor connection and black +ve -ve inputs
 same HV board from slightly different angle showing sense wire connection
  same HV board showing other inductor connection in white hall effect sensor and output terminal
Controller board in situ

Prepping for MOT

So the final pieces of the jigsaw are to fit a couple of automotive relays.

(1 for the vacuum pump for the brakes and 1 to disconnect the PSU/DC-DC convertor when the ignition is switched off as this causes the 12v battery to drain to overnight.)

And to get the EMW charger testing completed, get the charger working and charge the 3rd (Front) battery box.

It was my dad’s 70th birthday this last weekend so Saturday evening was already booked.

I spent most of Saturday morning working out how to use 12V automotive relays and fitting both the rear PSU/DC-DC convertor cut off relay and the front vacuum assist brake pump relay, wiring it through the vacuum sensor.

I tested it by wiring the relay direct to 12V switching on the relay permanently and adjusting the vacuum sensor sensitivity down until it settled a little.

I may need to service the vacuum pump or the vacuum chamber on the car as it did not seem to hold the vacuum for very long before the sensor detected a drop in vacuum pressure and kicked on the pump again, however it did definitely respond to me pressing the brake pedal as expected and refreshing the vacuum ready for the next push. Great :-)

So all I have left to do here is find an 12V ignition wire somewhere near the front of the car and route it to the positive input on the relay so the vacuum pump only runs when the ignition is on.

However there was never a need for 12V ignition in the front of this rear wheel mid-engine beauty, so I will need to go hunting under the dashboard for an ignition feed to finish this.

The car is booked in to the mechanics to have its final fix before MOT on Tuesday of this week (24th) Brent just needs to make a battery tray from some angle iron  for the 12V  Battery and fix all the HV cabling to the body proper as it is just secured to brake pipes at the moment with zip ties.

So Sunday morning I got down to charger testing.

Tuesday 17 September 2013

Honda Beat EV takes its first drive

Saturday 14th September, got stuck into the car early on Saturday morning as Steve was planning to visit and give me a hand getting the car going, removed the throttle position assembly and took it indoors to do a full breakdown and check (on Steves advice) I can believe I did not do this initially but I guess I thought there was not much that could be done wrong here.

How wrong was I, after emailing Steve last week he had advised I took the TPS assembly out and diagnosed it on the bench to make sure It was putting out a clean 0-5V signal from zero throttle position to 5V max throttle position, plus I had a sneaky feeling that I may have put the magnets in wrong (when I got the TPS assembly from Steve it had no magnets or sensor fitted).

Spent half an hour or so re-soldering the sensor to the throttle cable to allow for better insulation of each TPS sensor wire, it’s a very small sensor, and the hole it fits into is not much larger either so it leaves very little space to insulate everything.

Wired it up to my bench PSU and gave it 5V monitored output signal and waved the sensor at the magnets, nothing not a dickybird!

I was beginning to wonder if the TPS was stuffed when I discovered that the hall effect sensor only works when it is in close proximity to the magnets so I fitted the sensor in its housing and screwed this into the TPS assembly and voila I had needle movement on my DVM, spent the next 30 minutes discovering that I had the magnets 90 degrees out of phase and one set reverse orientated, corrected all of this and I had a good signal coming out of the TPS, Time to put it back in the car.

Refitted the TPS assembly and fired up the Soliton for a recalibration of the throttle, there was no apparent change until I touched the throttle after recalibrating and heard the pleasing sound of the Kostov whirring into life

WICKED, IT WORKS! “Quick love get the camera” I shouted to my partner and here is the result.



Friday 13 September 2013

EMW Charger testing continued

Carried on testing the EMW charger after I charged the car last night with Steve’s Zivan, I checked the voltages on the A7520 and found 0V on all pins bar pin 6 & 8 which had 4.82V on them, reported this back to Valery and await his advice.

Also I removed the charger box from the boot last night after marking the final hole that needs drilling to accommodate the +ve feed to the battery pack.

I had to change this slightly as I originally thought I could connect both +ve & -ve from the battery connections on the Soliton to the charger but of course the contactor set (which is not in the boot) would prevent this so I cut and crimped an additional length of cable to give the +ve feed from the charger the battery side of the contactor set.

Steve has said he may make it over tomorrow (Saturday) so hopefully I may get the car moving this weekend.

Need to remove the Throttle Assy and diagnose on the bench to get a proper 0-5V range coming out of the sensor, I must have the magnets fitted wrongly or something will investigate tonight.

Also need to move the shunt onto the negative battery terminal and hopefully Steve can help me setup the “Large Cycle Analyst” as well on Saturday as I have not a clue what to do with it.

1st Charge (from Steves Zivan) @ 20:20 on 12/09/2013 (2 packs only @ 148V)

Borrowed Steves Zivan last night he also gave me the Cycle analyst and the Shunt (which I mistook for a fuse and put inline with the +ve before charging, DUMMY!)

Steve corrected me with a ”Fuse what fuse! You don't mean the shunt I gave you do you?” DOH!
Still as the pack was at empty I luckily did not cause any damage to Steve’s Zivan.

It responded as expected and I left it charging for 1 hour as Steve recommended that should be good for 15 miles or so.

Disconnected the Zivan and switched on the car connected laptop to Soliton and checked status, “Pack Low Voltage” messages had disappeared so I assumed I would be good to drive (Wrong)

I then spent an hour or so trying to calibrate the throttle sensor again, I think I may have the TPS mechanics badly setup or something, when I got the TPS body it had no magnets fitted and no sensor, I  bought the sensor and wired that myself (Correctly according  to datasheet AFAIK) however I guessed at the magnet orientation I am checking this with Steve now.

The TPS body I am using is from a motorcycle and has been bolted into the car by Brent the mechanic this is all fine, however when I disassemble the TPS body, the part that moves inside is a “C” shaped metal bracket with two small recesses for the magnets at each end of the “C” these recesses are just the right size to fit two magnets at each end of the “C” however I guessed at the orientation so I may have inadvertently created a confusing magnetic field for the hall effect sensor and this may be why I am getting inconsistent readings from the throttle .

I am checking this also with Steve, in fact I think I will need to get Steve over soon to give me a hand setting up the cycle analyst as well as ironing out the last few things to get me moving.

Charger Delays

Fixed the garbled screen by adding loads of CLRSCRN statements before the PRINTSTR statements, still not sure that the LM211P is not fried, but Valery thinks not (I ordered one anyway just to be sure) everything follows the test procedure normally until I get to the “Short the output terminals” section which should then do a Zero Volt calibration, instead it just skips straight to the Power config (not right)
Ok so I am progressing with the charger slowly can’t get it to do the Zero Point calibration at the moment and I have been emailing Valery for advice.
Still Steve has offered me his Zivan to charge and test the car it can’t do a full charge but if I charge it for an hour or 2 it should get the car running adequately to get it down to Brent for the final fitting and MOTing I hope.
Brent needs to weld me a 12V battery holder bracket and fit all the HV cables properly to the car (rather than Zip ties to the Brake pipes as they are now) he also needs to fix the contactor to the car.
But that should be about it, Damn it’s getting close now.
Can’t wait to see what this baby can do.

Monday 9 September 2013

12V charger Testing begins

On Sunday after the show I spent the day testing the charger, swapped out the blown 2n2222, reoriented the LM211P and hoped for the best, fired up and “It’s alive”, well the LCD panel lit and displayed the 4D systems logo, no smoke or flames so looking good in my opinion.

A bit more reading and it looks like I need to upload firmware to get it going, wired in the firmware upload switch and tried again no joy! the Arduino flashes when I connect but does not upload, remembered a jumper under the Arduino checked the Schematic and it looks like the link supplies the LCD with power, The instructions refer to using the programming switch to turn off the LCD so you can upload software, so I tried it with this jumper removed and voila it worked! YEY

So now when I power up the charger I get a screen asking me to select the battery type showing “LIFEPO” which is exactly what I should see, YEY.

However when I select the battery type it moves to the next screen without clearing the last garbling the text on screen every step just makes it worse so I will need to fix this first before I can test safely.

Fired off a message to Valery and posted on the diyelectriccar forum as well, spent the rest of Sunday prepping the +ve and –ve output cables and realized that now I have fitted the contactor the battery terminal is no longer in the boot with the charger (Dammn!) Still I put it where it is on Steve’s advice to keep the cable as short as possible that way eliminating any long live cables however now considering the charger position I will need 2 meters more “220V Permanently LIVE” cable to connect the charger to the battery otherwise I would need to leave the car on all night whilst I charged and I would be putting my charge power through the contactor set not a good idea me thinks, I will need to check all of this with Steve before wiring up.

So close I can smell the rubber burnin ;-) Two more weeks and she should be road legal :-)

Brighton Mini Maker Fair 2013

Whew that was hectic, Unfortunately the car was not road legal so I was unable to tow it to the show and Brent’s trailer needs a large truck to pull it and his was off the road for servicing.

So we printed out loads of pictures of the car, took the charger internals not quite finished but nearly complete, the J1772 lead & plug and a copper buss bar for examples and wrote up a quick synopsis of “Why You Should Convert Your Own Electric Car”

I also took my 3D printer and loads of 3D printed things as examples.

I was amazed at the response the fair was packed must have been at least 5000 people, I reckon 1000 of them came to our stand we were luckily brought indoors as we did not have the car and printing in the wind or even a breeze is almost impossible.

They put us near the door which meant we had quite a lot of natural light which was nice, some of the stands looked more like dungeons in dark and gloomy corners.

There were a lot of stands doing 3D printing but I only saw one other actually printing this does seem to be a trait of these fairs in that loads of 3D printers arrive but only 1 or 2 actually print anything on the day! MAD!

Loads of people commended me on the quality of the parts I had produced and the variation in colours and plastic types, I had ABS, PLA and CAPA/PCL on show.

Got lots of interest in the EV, Printed out a load of last minute contact sheets so I may get some feedback after the event, got invited to an EV race at Goodwood I hope that guy gets back to me sounds like fun, and lost my voice by the end of the day so all in all I think it went pretty well.

Next year I will be much more prepared, hopefully not trying to get the RX8 completed in time for the show ;-)

Sunday 8 September 2013

Burnin the candle!

The early morning’s and late nights are starting  to take their toll now, Wednesday night I loaded the two complete rear batt boxes and wired up the Soliton Jr to the IGN 12V feed and wired the Contactor (big HV relay) with the batteries not connected I turned the Ignition key to hear the gorgeous sound of the HV contactor “click” the HV relay shortly followed by the whir of the Soliton Jr fans.



ITS ALIVE (Well almost)

1st Low voltage live test complete, hurrah!

Boyed by that success and due to the failing light now summer is nearing its end I went inside to fire up the charger for it’s 1st Low voltage 12V test and ½ second in LCD came on as expected began boot up “Snap", "Crackle" – I did not wait for the POP!

Fried a 2n2222 transistor, must be a short will investigate tonight ,still looked promising there for a split second.

(Update:- checked this last night and spotted my schoolboy error, I had inadvertently reverse orientated the LM211P IC that feeds the S3 2n2222, DUMMY!)

Ho Hum, I am guessing it has fried the LM211P although it appears that the 2n2222 S3 has taken the brunt of the damage, luckily I have these in stock so I have fired of a post to the diyelectriccar forum’s 10KW charger thread to see if Valery can suggest the symptoms of a fugged LM 211P, this is so that if I replace the definitely fried 2n2222 (S3) and orientate the LM211P correctly I am hoping that I may not have fried the LM211P and it may well be still useable.

If Valery suggests the symptoms of a dead LM211P I should be able to test it and identify if I have killed it or not.

Last night (Thursday 5th) I wired the motor for series field mode clockwise orientation (not sure if it needs clockwise or anticlockwise to give forward motion through the transverse gearbox but I am taking a wild guess at clockwise due to the layout and logical look of how it is laid out. If it is wrong it’s very simple to change.

Also wired in a temporary throttle cable by twisting 2 pairs in an old shielded DIN cable I had laying around (this is definitely not good enough for actual use but I have already ordered an appropriate cable just waiting for it to arrive) basically using 2 cores twisted together to cover the potential 1A current draw (although it will likely be much less as it is only a 5V hall effect sensor probably draws micro/milli amps)

(Update:- The cable I bought turned up and is thinner than I thought So my temporary bodge is probably better than this anyway! Will check with Steve as to what is actually required for Safety’s sake)

Also the new 12V cables arrived 5 meters of each, black and red, silicone insulated, ran these through the car from front to back (in the case of the red +ve) and a short link for the –ve to chassis.
Threaded the red alongside the HV cables, both the HV cables and the 12V +ve are currently just zip fastened to the brake fluid lines in the tunnel that runs under the center down the whole length of the car, this is definitely not safe and once the car is running it will be going back to Brent for him to safely secure all the wiring looms in place properly.


Tuesday 3 September 2013

Last week before the Brighton Mini Maker Fair!

Ok, it's the big push.

Met Steve at SMD (the mechanics) on Friday 30th to get a lesson in how to wire a 220V EV battery without killing yourself.

Unfortunately the neoprene tape I had ordered was taking a little longer to arrive than I had expected and was not there on Friday so we used Gaffer tape and some foam tape I had as a temporary replacement and I wired a box (1 of 3) with Steve looking on to make sure I knew what I was doing, Steve suggested a good idea of using elastic bands to separate the banks from each other and the positives in each bank from the negatives in each bank, this way it is much easier to follow what you are doing closely double checking each and every connection you make (one wrong positive from a different bank and BANG say goodbye to a finger potentially, wiring a LIPO battery is not for the faint of heart)

Anyway after a lot of talking with Steve on how to wire the car, towed it home from the mechanics back to mine a 5 min journey, with Steve at the wheel (thanks again Steve) and by Friday at around 4:30PM the car was at my home ready for the final stage wiring!


Saturday 31st Aug

Neoprene arrived this morning so I was able to get straight down to wiring up the batteries proper, I had two wiring layout  options I went for the slightly more complicated to wire up method which would give a better end layout of the buss bars in the top of the boxes, following Steve’s advice as how to wire them (slowly checking every connection from each banded bundle wiring only 1 buss bar at a time and then insulating it completely with the wide neoprene self-adhesive tape before moving on to the next one.



Once I had done all the buss bars I moved onto the LVC/HVC cut-off boards Steve had forgotten to bring the HVC/LVC extender boards, so I picked them up on Sunday, Thanks again Steve for being available at weekends.

I also picked up a HV fuse and contactor set from Steve, Forgot to pick up the magnets for the throttle position sensor (TPS) however, my ever loving partner picked these up yesterday (Monday 2nd) as she is as keen as I to see this baby on the road.

On Saturday I ran most of the HV cables into the car and cut them to length, on Steve’s advice I cut 200mm tails from these measured cables to make the terminal connections for the battery packs, this is to avoid the need to take the lids off the battery boxes in the car in order to get them in and out of the car, obvious really.

Crimped up the terminal tails and connected them to the buss bars in the battery boxes, finished the last box on Monday evening, insulated the inside of the batt box lids and screwed all 3 lids in place.
So by Monday evening I had finished the batteries, fitted in most of the HV cable (bar the small bits that wire the motor into Series field mode) wired in the 12V battery connection from the new Lifepo 12V battery block, Damn it’s light not sure if I can charge this from a standard 12 car battery charger I guess not as it would probably damage the battery.

Wired the Live & Neutral connections (these connect to the battery side of the Soliton Jr) for the DC-DC convertor that will take the place of the alternator and keep the 12V battery charged when the car is in use, this prevent voltage drop when you switch on lights heaters or use the electric windows for example (I am actually using a cheap power supply as a DC-DC convertor as genuine DC-DC convertors are very expensive, According to Steve he has had several arguments with people over this one and although others have said this will not/cannot work, it does!) essentially you are just using it as a voltage step-down transformer

Wired the +ve out from the PSU/DC-DC convertor, Wired the signal grounds for the Soliton Jr, Crimped up most of the HV cables (bar the front battery box as the light was fading by then)
Which just leaves :-

1) Wire throttle position sensor

2) Wire the vacuum pump sensor/switch

3) Fit two rear batt boxes (will be testing with just the two rear boxes giving 148V)

4) Fit fuse between two rear batt boxes, I am told by Steve that a fuse is better placed in the middle of a pack to minimize the potential difference at any one point (to 74V in this case which is “fairly” safe)

5) Fit HV contactor, Just ground and ignition wires I think, This is the big relay that switches on the battery pack when I turn the key

6) Wire the motor in Series field mode, the motor has 6 big pins, connect them one way for series field mode the other for parallel field mode, details on the spec sheet from Kostov.

7) Find an ignition signal in the rear of the car for connection to Soliton Jr, charger, contactor etc.

I am sure there is loads more that I have forgotten, but gotta go now and get to it.

Monday 2 September 2013

CNC Heaven

Last weekend whilst I was waiting for the buss bars to be finished I arranged with Steve to move his CNC mill from his workshop to mine, I have done a deal with Steve to swap it for a decent sized 3D printer probably a Mendle 90 derivative along with support for the printer until Steve is up to speed with using it properly.

So this weekend my ever loving partner Michelle contacted a good friend of mine Simon who has an open back truck and engine lifter and armed with this we went over to Steve’s workshop on Sunday and collected the Seig KX3 CNC Mill and moved it and it’s bench and PC over to my workshop, I then spent the next 12 hours (11:30AM to 11:15PM) fixing the software problem I had caused and figuring out how to home the machine properly.

I am sure a pro would tell me how wrong I am but I figured out that by using a combination of the “offline” button and the “goto zero” button I could break the connection between the software and the machine and home the software’s work position back to zero without moving the machine at all then put the software back online and run the G code program, this way I am able at least to use the machine, however I only have a drill chuck as Steve could not find the collet chuck and I only have 1 bed clamp so I am going to need to invest in some new tools and bits for the CNC.



Started a new blog here for the CNC project as it is so coooool ;-)

http://kx3cnc.blogspot.co.uk/

Bus Bar Problems

OK I should have guessed that this would not be as straight forward as I thought it would, basically on Thursday I spent 4 hours demonstrating to Steve that I have no idea how to use a CNC machine properly, failed to get it homing to the start point of the work piece, and then in my efforts to solve this managed to break the software so that the machine was erroring through the Mach 3 software GUI, Never mind we decided to try the Bridgeport the following day.

Friday did not go any better either spent an hour searching Steve’s workshop for the correct chuck and drill bits to do the job failed here as well, decided after a couple of hours that it was best to cut my losses and get the bars drilled professionally, the real problem is tolerance, according to Steve the holes have to be a very tight fit so that the plugs and sockets will press fit and not fall out when the bars are heated for soldering.

Spent the next 2 weeks looking for someone who could do the job ASAP eventually found a company called Mach4 in the Newhaven industrial estate that was able to do it, however that day they said they were doing the job they called to explain much to their embarrassment that the machine that they were using had broken and was being repaired the following day the owner of the business Tim was not happy and explained that tit was costing them £300 per day while the machine was down and the maintenance company were aware of this, luckily Mach4 are a pro outfit and said that if it was not fixed by Tuesday (2 days after they said it would be done they would use another machine that had just finished a run of parts.

By the following Tuesday they called me around lunchtime to say the job was done and I took the afternoon off work as holiday so that I could pick up the bars and get them to Steve also I had to do the brake pads on my ICE car that were squealing.

So it is now Thursday 29th of August the BMMF is on the 7th (a week tomorrow) and I have booked Friday afternoon off work to wire the batteries and car up with Steve.

I just hope there is enough time left before the show to finish the car or at least get it roiling.

Last few weeks/days now :-)

Now things are really getting exiting, I have Wednesday and Friday off work this week (it’s Monday 5th today as I am writing this) Wednesday to spend the day with Steve making all the buss-bars for the battery pack and soldering 216 terminals onto the batteries and connecting the whole lot up.
And Friday to wire up as much of the rest of the car as we can manage in a day!

I have been in a charger build frenzy this week trying desperately to finish the charger so it is ready ASAP for testing.

Since my last charger post I have finished the final assembly of the boards and fitted all the heat sink mounted components onto the heat sink with thermal compound, made 3D printed brackets to fit the LCD panel to the lid and hold the lid on the box, drilled several holes in the box to mount it into the car and to mount the heat sink securely inside the box.

I have drilled and fitted the thermistor & wired up most of the low voltage wiring, cleaned (sanded) the whole box on the outside to improve the appearance (slightly) and sanded the lid to a shine as this is the only bit of the charger you will see when it is secured in the car.

Yesterday (Sunday) I fitted all the printed brackets to the lid after drilling out all the button holes for the controller and lined the box with some old corrugated plastic to protect against potential shorts.
AFAIK all that remains to do on the charger is wire the AC input side to the choc-bloc holding the inrush resistors, secure the choc-bloc to the inside of the box somewhere where it will get adequate cooling, drill a shitload of holes both sides of the Ali charger box to allow for inlet and outlet for cooling, fit some fat fans to draw the air through the box, these will probably be external, possibly mounted inside the engine (Motor) bay and will suck air out of the charger and into the exposed engine bay

I also need to wire up the 12V transformer and connect it to the AC input side and to the 12V input on the driver board, secure the 12V transformer into the box (more 3D printed brackets!) drill (more) holes in the box.