Archive for April, 2010

Real drive into work

Thursday, April 22nd, 2010

Interesting drive.  Naturally I was unable to gather stats on the drive in, as the RS232 connector came loose.  *shrug*  Time for duct tape.  🙂  The drive home was successful, in that I was able to gather data.  It also showed that I have some transaxle noise that needs looking at before I drive much more (Calling Dr. 914!)

So for those who are statistics fiends:

Current: min=-48a, max=123a

Voltage:  min=330v, max=368.5v

Torque: min=68.6nm, max=120nm

I’ve attached the spreadsheet with all the data, so you can analyze it to your hearts content:  InitialDriveHome

Oh – the current at freeway cruise was between 75 and 80 amps at 350v.

Full charge!

Tuesday, April 20th, 2010

I returned from my business trip to Bangkok (long story in itself) to find two boxes waiting for me – the replacement DC-DC converter and new cables for the BMS.  It took me about 4 hours to replace the DC-DC converter and the 4 cables, but well worth the effort.  The DC-DC converter works as advertised, providing 13.5 volts. The new cables eliminated the intermittent communications problems during charging.

Proof is that the batteries are now fully charged.  I can see the car quivering with excitement in the driveway, begging to be driven.  I think I’ll do that today.  🙂

BTW, EV Components has been great during all of this – providing excellent customer support and fast shipping of new parts.


Tuesday, April 6th, 2010

Ok, so some tweaks on the pedal parameters make a HUGE difference.  I was able to get the accelerator to behave “normally”, and was able to get the regen to work with the brakes.  Acceleration is good – better than the 1.8 liter engine. Braking is GREAT!  Dang, I sure don’t need those high-priced brake upgrades now.  🙂

So now I get to do some fine tuning on the pedal, and it will be driving like a REAL car.  😀  I was able to pull only 90 amps, so I know there is more to push through.

Seriously, though, I was able to get up to 30 mph in first gear with no trouble, although there is a lot of vibration at 5k rpm, so I will have to pull the motor and balance the flywheel.  *sigh*

So now I am waiting for the replacement DC-DC converter (previous one sadly fried due to operator error) and some cable components so I can rewire the BMS circuits.

The BMS works fine except for banks 5, 6 and 8.  Oddly bank 7 is fine, but I will rewire it also, as it uses the Cheap Cabling.  Hopefully this will take care of the communications errors with the BMS.

Alive again

Saturday, April 3rd, 2010

Ok, so in the process of trying to “optimize” the driving experience, I made a few mistakes.  Fortunately, I’ve been able to fix almost all of them. The regen circuit now is activated by the brake lights, so the car now drives just like a car.  Very cool.

While I was fussing around in the controller compartment, I tried to get the DC-DC converter to work.  However, this resulted in me frying my DC-DC converter (fortunately, this is an relatively inexpensive mistake).  The good thing is that EV Components has more of them.

I’m hoping to get the tachometer working tomorrow.  I spent about 3 hours getting a neat circuit put together that will drive some indicator lights.  One is the “ready” signal and the other is the “fault” signal – both from the motor controller.  Since I know I’ll want to see these lights while driving and while testing, I set it up so there are two of each lights – one set in the dash and one set near the motor controller.

Radio Shack was my friend, as was Tim Kutscha for his diagram.  Naturally, I didn’t do it exactly his way, but that is the fun of all of this. This version uses 2 resisters – one for each input and 4 transisters – one for each light.  The box has 12v ready LEDs, the other lights are the more usual incandescent lights.

The circuit is inside this box:

Das Blinken Lighten

Circuit for showing "Ready" and "Fault"