Vogue Almost Together again - shunt wire wrong!

The Vogue engine bay is almost back together. During the re-fit, I am using a lot more split conduit tubing than I originally installed after reading about a commercial EV converter's product that appears to suffer from "chaffed wiring" amongst other things. I've probably gone a bit overboard. There are many places where the traction wiring is now triple insulated but better safe than sorry. I'm also trying to neaten up the control wiring a bit.

The shunt wire for my chargers arrived and I find that Ni-chrome wire is just as it always was - not able to be soldered. We crimped on some pin crimps but the resistance worked out almost double what it should have been and varied under physical stress so I gave that away as a bad idea.

So - I have ordered ten 0.015 Ohm shunts from element14. I didn't really need ten as I can make up half of the shunts from two of the old removed shunts soldered together but the price break was ten.

I didn't want to use these originally as they are a bit large (lead spacing). I just have to assume that I can bend them without any problems.
I was really annoyed to see that that element14 have dropped their free shipping on any internet order so its probably the last time I'll use them. It's not that much of a detour for me to go past another electronics supplier on my way to work.

Controller Tray Rivnuts Installed

I replaced all twelve of the M4 nuts and bolts on the controller tray with M4 Rivnuts last night. It meant drilling out the 4mm holes to a fraction over 6mm. The last two were a pain as I managed to chip the leading edge of my 6mm cobolt drill bit. Anyway, now the two charger stacks and the Fuse/Contactor box on the tray can be removed easily. I have added the daughter board to 8 of the chargers so only four to go. The low current setting varies from 230 to 350mA across the chargers I have modified so far (I want 180mA) so I hope my new shunt wire arrives soon.

Rotor in, Motor in

I have re-installed the rotor back in the motor, fitted the shaft encoder and re-fitted my IP65 spray can lid. The only silicone I had was the high temperature stuff that I used on the heater core. That worked nicely.

I'm glad border adhesive is useful for something (weight). After the huge trouble we had stripping it off my daughter's bedroom wall we swore we would never use it again.

Since I had to wait a day for the silicone to set, I turned my attention to the chargers and controller tray. I am going to drill out all the 4mm holes and use M4 rivnuts so that I can get stuff off the tray without having to remove it (the tray). I ran out and bought a 6mm cobolt drill (for stainless steel - it works really well) and tried to use a manual method to insert the rivnut - no good. I'll take the tray to work and see if I can use the tool there. So the tray is in the boot of the Super Snipe.

The blue circles are some of the 4mm holes - the red is a 6mm hole I have drilled out.
The DC-DC block (still on tray) is another matter. It's held on with M6 bolts through the bottom from inside the case (nuts underneath). It isn't impossible to get off without removing the tray - just difficult.




As of Sunday afternoon, the motor is back in the car.
It took me and William about an hour of messing around with a jemmy bar and many blocks of wood to get the rear of the motor to a height where I could get the Jack under it. From there it was relatively easy.

I have about half the chargers (six) left to modify. I have to change the current shunts in all the chargers to finalize my modifications for two current settings - 3A and 180mA. I have ordered some shunt wire but it's not due for a week or so. I can still finish installing the controller tray since the rivnuts will allow me to install the chargers afterwards.

Daughter board for current switching shown circled.

My two spare chargers (where I tested this modification) didn't need the shunts changed - they were 12 milliohm. The twelve chargers in the car appear to have anything from 6 to 9 milliohm shunts which makes the low current setting too high - hence the shunt change.

The modification allows the charger to charge at 3 Amps then, when the current drops to less than 300mA, the charger switches to 180mA Constant Current - which is the value that the rudman regulators (cell bypass resistors) in my packs are set. It'll means that charging the car is a set and forget operation - which is as it should be.

The Rotor is back!

I just picked up the rotor from Precision Balancing.

The motor rotor in the boot of the Super Snipe.

Before balancing the rotor balance was 7.43g (grams) out at 18 degrees and the other end 14.4g at 191 degrees.
After balancing it is now 0.550 at 328 degrees and 0.532g at 320 degrees.
It sounds a lot like it was statically balanced originally.
They also balanced the coupler after balancing the rotor - it'll need painting again (I'll probably stuff the balance!). You can just see the shaved part of the coupler on the top (red thing on end of rotor).
This will make a big didn't make any difference - now to get it all back together.

Motor Is Out - again

I stripped the engine bay on Saturday, went for a day trip to see a relative in Shepparton on Sunday, and removed the motor on Monday (today). I decided not to remove part of the finished interior to use the "rope trick" to get the motor off the jack.

Picture from July 2010

Instead I had two helpers use a wooden pole to hold the rear of the motor cradle up while I slipped the jack out. I load tested the pole with my weight before trying this. They indicated that they don't really want to help put it back in the same way (It wasn't easy). The red arrow is pointing at the pole - picture taken just before I went inside to fetch Laurel and my daughter's boyfriend to help (no-one is safe!).

Picture today (11th Mar 2013)

Since never got around to taking a picture of how I increased the IP rating of my little shaft encoder I took the opportunity this time. I had siliconed a spray can lid over the encoder - see red arrow. The black steel ring, also siliconed up, has a small gap in the silicone at the bottom to allow condensation to drain. (Blue arrow points to silicone around spray can cap).

I had to remove the spray cab lid again and was pleased that the silicone, which was past "use by" at the time (getting a bit jelly like), held on nicely. I'll use fresh stuff this time.
Shortly after this picture was taken I took the rotor out. It's in the boot of the Super Snipe now.

Driveline Vibration Identified

Last night I removed the driveshaft and ran the motor with coupler still attached. The vibration kicked in at 2000 RPM (50 km/h), faded a bit as the speed increased then kicked in again at 3800-4000 RPM (100 km/h). I removed the coupler and ran it again with exactly the same result.
The vibration was no-where near as bad as with the tailshaft - but quite definitely present and at the same speeds that I am getting the vibration with tailshaft attached.
So the motor is apparently the root cause.

I spoke to Jeff at Precision Balancing (who made the driveshaft) this morning and he asked where the motor was made then indicated that he does lots of Induction Motors for higher speed and the nominal rotor balance is only ever "just enough" for their nominal running speed - in my case 1500 RPM. There was some complication to do with a language barrier around the time I was discussing rotor balance with Qin Wei (the motor manufacturer in Taiwan) - only that they indicated that it would be fine to 4000 RPM..

So I'll strip the engine bay, drop the motor cradle, remove the motor then remove the rotor and take it up to Jeff. He also warned me to check the bearings for a speed rating. They are NSK bearings but I'll have them out anyway when the rotor comes out so I'll check.

Moral - balance those rotors.

A point here is that this probably wouldn't be a problem in a FWD where the motor was hard coupled to the gearbox. The rubber mounts in my case allow some movement that appears to be amplified by the tailshaft.

More on the Drive Shaft

I had Laurel run the driveshaft up to 50-60km/h while I crawled under the car yesterday morning. I placed a hand on the underside of the motor then down under the diff. It's definitely coming from the end near the motor.

Here is a annointed picture of the front of the driveshaft and motor coupler.

Also, to clarify. I understand that the driveshaft can not be on a 0 degree angle from the motor. In the previous post I actually did not measure the drive shaft angle. I was using the motor angle as a reference to try to get the differential pinion angle the same (diff and motor flange faces aligned). Either way, it seems the diff pinion angle is not the culprit.

In search of the Drive line vibration

I placed the Vogue on axle stands on Sunday and removed the rear wheels.

I measured the angle of the motor, so close to 0 degrees that it didn't matter. Then I measured the differential pinion angle. I did it two ways. The first was to place the level across the back of the diff flange. It calculated out at around 2.3 degrees. Then I used a trick I read about on a hotrodders forum. You align the tailshaft so the uni is pointing straight up and place a socket on the needle roller cup. The socket has to be the largest you can fit without it riding on the circlip. Then place the level on the top of the socket. That came out at just over 2 degrees as well.

We placed the jack under the front of the differential and jacked it until the pinion angle went to 0 degrees - the springs took it up easily. I thought I would have to loosen the U bolts (axle to springs) but it wasn't necessary.

Then we ran the drive system up to about 50km/h, noted the vibration (which I had hoped would be gone) and slowly released the jack - no change.
It was the same at 100km/h. Laurel thought it was a bit better but I was going for complete cure.

My next guess is the pinion bearing (somewhere in the middle of the night this occured to me). I quickly crawled under the car this morning and tried to give the pinion bearing a rattle - I grabbed the diff flange and wobbled it up and down with all my strength.
It felt totally secure - no give at all.

I'm now at the stage where I'm ready to find a good drive shaft specialist and give them the problem.

Pack #2 fixed

I built a new BMS monitor board, cleaned the underside with an aerosol cleaner for PCBs (at work) and sprayed it with a copper and brass laquer I had at home. Pack #2 is reassembled and back in the car.