Last Charger Inline Fuseholder Replaced

I was about 1km into my trip to work this morning when the battery alarm went off.
Pack #3 in the boot (trunk) had it's indicator LED out so I bypassed the pack and continued to work - I wasn't even late.
At work I bypassed the VERY LAST of the inline fuseholders. Pack #3 was the last one and it visually had been looking OK (easy to see in the boot behind the polycarbonate partition) - but is wasn't - the fuse had melted it's way out through the end of the fuseholder. (For the full story click "fuse" in the Labels area on the right hand side of the blog pages - or click here.)

I was a little suspicious this morning when I saw (on the smartmeter web interface) that the chargers hadn't peaked at 2.7kW at 1AM. House load is about 250-300W so I normally see a minimum of 3.1kW.

(The mouse was hovering over the first bar for 1AM.)

Only One Fuseholder Remains - Economy Figures

I didn't post it at the time, but last Tuesday night I removed three of the last four inline charger fuseholders. I have one left and it's only there because I ran out of 4mm black heatshrink and it was the only one that looked to be in perfect condition. I'll do it as soon as the heatshrink (from eBay) arrives. With the fuseholders gone the Vogue was completely trouble free for the commutes last week.

Figures for week ending 26th July 2013
Monday: 8.84 AH for 39.2 km => 135 Wh/km
Tuesday: 6.68 AH for 31.9 km => 126 Wh/km
Wednesday: 7.20 AH for 33.6 km => 129 Wh/km
Thursday: 9.81 AH for 43.4 km => 136 Wh/km
Friday: 9.38 AH for 42.9 km => 131 Wh/km

(All battery to wheel)

As a curiosity, I usually make it to work at about 3 AH consumed - that's around 1800 Wh making the economy about 120 Wh/km (my record so far is 2.8 AH). The trip home is a lot worse and I have generally racked up over 6.6 AH by the time the round trip is completed. The difference in altitude is about 20 meters so doesn't explain it - but driving style does. Going to work I am generally not hassled by any other drivers so I can accelerate slowly and slow down at my leisure taking full advantage of regen braking. Driving home is a relentless wrestle with other road users to use as much regen as possible but not get in their way. The nett result is that driving home is less efficient. Accelerating up hills costs a heap of capacity.

My observation is that not many drivers are in a hurry to get to work, but most road users are in a hurry to get home.

I could improve this situation with more regen. At the moment it peaks around 25 Amps (battery) which is 1.25C. Headway (battery manufacturer) recommend a continuous charge current of of 1C (20A) and maximum continuous charge of 2C (40A). Perhaps I'm being too conservative. I really haven't had much time to mess around with configuration in the past few weeks.

Banana shaped fuseholders

I mentioned a post or so ago that some of the inline charger fuseholders have melted out of shape a fair bit.
This one is on Pack #5 in the boot. It hasn't failed yet - amazing! (The large flat heatshrink bit houses the two 3A heatsunk diodes that isolate the charger from the pack and the lower black wire and clump are the inline fuseholder.)

I only have three of these inline fuseholder left in the car - out of 12.

Pack #9 gave a low voltage alert about 800 Meters from home last night. I gently eased the car home and sure enough, the fuseholder had failed and Pack #9 hadn't charged much the night before.

It was 44.3 V unloaded and charged up fine with a clip-lead replacing the fuseholder.

Last "under the car" fuseholder bypassed

I didn't get to play around with the tailshaft this weekend but I did manage to crawl around under a slightly raised car and bypass the last of the hard-to-get-at fuseholders (in series with chargers). This was the one attached to pack #10 that I mentioned in the previous post. There are now only six of the unreliable fuseholders left and none of them are hard to get at.

One of the fuseholders in the boot still works but the heat has bent it like a banana.

Three more fuseholders bypassed

I spent about an hour and a half under the front of the car last night squeezing my hands up beside the inner front guard to cut out two of the offending fuseholders (packs #11 and #12), substitute a length of wire, and heatshrink the whole lot. The time was mainly spent trying to line up two pieces of wire (several times) with only one hand (tried many clips etc.) and solder with the other - while scrunched up in strange positions.

I also did the same treatment to pack #8 in the Engine Bay.
Pack #10 inline charger fuseholder is also about to fail. It's the hardest pack to get at without removing the top battery tray so I'm hoping it will hold on a week or so as I will be removing that tray to change the heater blower soon. It's marginal - if you rattle the charger wire while charging, the charger cuts back to balance mode - sigh.

So, fully charged again,  Il drove the Vogue to work today.

Vibration wise. I have now driven the car for a couple of days and the vibration is only a little bit better than it was with the M8 bolts holding the front flange in (allowing the spigot to be centered). While 90 km/h is possible, it feels the the motor bearings won't survive long. It's going to be a wet, cold weekend so I hope that I both get the time, and the enthusiasm to brave the cold and check it out further. I have my hose-clamps ready.

Timer waits for no-one - Neither do inline fuses!

I didn't drive the Vogue today - there were too many obstacles.
Firstly, last night I plugged into my wall timer and checked that is was set to auto - only to find that it had stopped entirely. The timer is a Chinese copy of the TP8A16, 16A 240 VAC timer.

It was designed to come apart, so come apart it did!

The 1.2V, 80mA/h NiMh button battery had EXPLODED.

I removed the cell and checked out the rest of the board - it appeared fine after a little cleanup.
A quick reverse engineer and I discovered that they use the battery as a 1.4 volt regulator. Without the battery there is about 6 volts at that point. The electronics doesn't like that so it didn't work. When I turned off the 240VAC, it worked for a few seconds as the voltage went down through the acceptable region. So the electonics was probably OK (amazing).

I removed the exploded cell and substituted two diodes in series where the battery used to be. It all worked fine. It only lasted about 5 seconds after mains disconnect but that would do for the night.

At least they used a 16 A relay.

I went out to the car at around 6:45AM this morning to check all was well (timer was set to start at 5AM and finish at 8AM) - but all was not well. I charge at 3 Amps and needed 6.6AH - so a bit over 2 hours required.

Battery pack #12 was indicating finished charging - all the rest were still charging as they should have been.
I checked pack #12 and it certainly wasn't fully charged - another inline fuseholder! I should have had them all changed out by now - oh well. previous fuseholder failure

Pack #12 is under the controller tray and hard to get at so I'll take my daughter's car as she is not due home until Thursday and I have to give it a full tank and wash it anyway.
That way the Vogue is also in the carport for some wiring surgery tonight. I'll try to bypass all three fuseholders under the engine bay without removing the controller tray. I'll see how I go...

Charger Mods Done

I have finished modifying all the chargers and was pleased to come out this morning to the Vogue with every pack charged and fully balanced. This is the first time all the packs have been fully balanced at the same time and will be the norm from now on.
I had yet another fuse holder fail Wednesday night sometime and Pack #1 (boot) didn't charge for my drive to work on Thursday. I bypassed it at work and charged just that pack - so it didn't stop me.

I just have to get rid of those pesky fuseholders now.

Third day as daily and Battery Alarm sounds

On was on my way home last night and stopped at a major intersection to turn right. When I got the green arrow and moved off, the battery alarm alert started. I pulled over as soon as practical and popped the bonnet. (I do not yet have my controller keypad in the cabin which tells me which of three regions in the car the alert came from). All the blue lights were still lit on the engine bay packs. I moved around to the boot - and it was LOCKED. So I turned the car off, unlocked the boot (I needed the key from the ignition) and got back in and started driving again. The alert started within 10 seconds. I stopped again and checked the boot packs. Pack #4's light was off.

At this point I should have bypassed pack #4 which would have taken all of two minutes but for some foggy reason I decided to limp the 3 km home.
I got home OK (annoyed a bit of traffic) and checked voltages on all packs. Most packs were 52.4 VDC. Pack #4 was 36 VDC. In my mind I had clearly ruined some cells.

I placed the car on charge and within a few seconds the charger light for pack #4 showed it was fully charged. Hmmm. To cut to the chase, the inline fuse from the charger to the pack was very hot and the fuse holder was melted and at a strange angle.

The diode isolator and inline fuse assemblies for the chargers.

This is the second fuse holder that has melted - I replaced the one on pack #12 about three weeks ago. These fuses only take 3 Amps but it appears to be too much for the el-cheapo fuse holder.

I pulled the diode/fuse assembly out and soldered in a fuse directly and heatshrunk it with a couple of layers. I then placed pack #4 back on charge. It didn't get hot at all after that. Pack #4 took a full 3 Amps for more than 6 hours so it clearly survived and I learnt some helpful clues.

Clue #1
According to the smart meter online monitor, the night after my 60 km day, the house drew 3 kW for an hour then 2.7 kW for 3 hours. The clue was that one charger had dropped out after the first hour (smartmeter resolution is 0.1 kW).

Clue #2
On the drive home, several kilometers before the alarm, the full pack voltage was dropping under 600 VDC regularly. I had not even seen that on the 60 km run, except under really heavy load. Now I know to pay attention.

Clue #3
No so much a clue as observation. Don't skimp on parts - especially cheap ones. I'll replace all the fuse holders as time permits and solder the fuses directly into the assemblies.

There are obviously down sides to the one-charger-per-pack system but the alert system obviously works fine. I need a reliable wireless mains power monitor for the EV outlet - the one I have is rubbish due to the non-linear power factor issue with the chargers (I think I'll crack the sender open and see what I can change/fudge).

The battery alarm drives you insane - it's very loud. I was originally concerned that you wouldn't hear it because it's up under the dash somewhere. The alarm also locks in and can't be cancelled without turning the car off - not hard to change but I'll see how it goes - It normally shouldn't go off anyway..

I am now carrying a short bypass cable and the tools to bypass a pack (and a multimeter) - the Vogue can run on as little as nine packs (I have twelve).
Yesterday's battery to wheel was 7.22 AH for 32.06 km => 132 wh/km
I drove the Vogue in again today.

Boot (Trunk) Electrics

Even though it's been a month since I last posted, stuff HAS been happening - just slowly.
The rear of the car will hold 5 of the battery packs, the mains inlet/charger sequencer (controlling the 12 chargers not coming on all at once), and the rear high-current contactor and fuses.

This is the are of the boot where the fuel tank lived. It was mounted vertically in the Vogue with the filler on top of the guard. There are two mounting points, one on the guard and one coming off the rear of the car. They uses a metal strap to hold the tank.

Here is what I need to mount.

The left hand one has a circuit breaker and earth fault relay and my logic/relay board. The right hand one is almost the same as the fuse/contactor box in the engine bay.

Since my welder person is unavailable I will build the mounting bracket from aluminium angle and lots of 6mm bolts and nuts. Step 1 - two vertical pieces of angle and some support.

Step 2 - horizontal pieces space vertically to fit the mounting holes on both boxes.

Poking the camera into the gap in the guard you can see another piece of angle to support the front mount laterally.

 The boxes mounted. I have put the dummy battery below them to check for fit. I will have to remove the cover on the mains inlet/charger controller box the get the battery pack out but that's OK.

View from the rear of the car showing the bigger picture. I have since pulled the whole lot out to weigh it and paint that area of the boot as it looked pretty gungy with old fish oil stains.

Now I know where the rear contactor box is located (I didn't really know until I did it) I can install the front to rear conduit and start the high current wiring.

The Real Fuse/Contactor Box

And here is the real one. Finished last night. This is the -ve version (for the boot). The +ve version has the contactor around the other way as the contactors are polarised.

The large cable glands on the left are for the orange traction cable, the smaller glands are for 12 V control and 600V low current.

Fuse and Contactor Boxes

One of these has to go in the boot and one in the engine bay.
I have already bought the boxes and have all the parts but I won't finalise them until I actually physically put some parts in the engine bay. The layout of the cable glands is quit critical as I don't have much room.
Anyway - this is what they will look like - clear covers too!
You can see this box on the left in the previous post with the engine bay sketch.
The real thing won't be nearly as colourful unfortunately.

More Components

We are having a new back door fitted (to the house) so I'm home this morning and using some of the time to update the Vogue blog.
I have added labels to make finding things a bit easier in the future.
I bought enough of this plastic sheeting to try as a door liner. It's pretty light which is good but it may be too light to mount the front speakers in.















It's 3 mm thick. Should be a breeze to put holes etc. in but is it strong enough?

Now to track down some kind of thin padding and spray adhesive.

I can't actually do it until we have the fabric but I can cut it to shape using the old door lining as a template.










More retrospective blogging. From eBay again!

This emergency stop switch will mount in the dash where the choke used to be. The choke is the far left-hand knob on the dash in the previous post about the dashpad.








The forward-neutral-reverse switch will mount where the generator (yes, not alternator) light used to be.






100 Amp 700 VDC fuses. I bought 9 of them on eBay (again!) about a month ago. I only need three of them but AEVA forum people have committed to take a few.

They are 110 mm long.