In which we visit The Discovery Museum
Got the beauty out of the garage a week and a half ago and started prepping for an April 24 visit to the wonderful Discovery Museum in Acton MA for a moment in their vacation week and Earth Day programming.
A little diagnostic journey was necessary, as the controller was shutting down as I drove. In these days of microcontrollers, it wasn't so hard to figure out. The Daly BMS told me the important part from its error log, all accessible by their iPhone app through a Bluetooth connection: The range of allowable voltage difference within the pack had been exceeded. Sure enough, I could see cell 24 (which is actually three smaller cells in parallel within one of the Hyundai modules) had sagged compared to its brethren by about 130 mV.
The fix *could* come from the BMS with an estimated six days of charging, as the model of BMS on board can only equalize in charging cycles. (Not on discharge, let alone as the pack just sits, in the form of "active balancing.") Best choice was to bring the voltage of that cell up separate from all. So I built a little charger and ran it off an on for about two days to bring 24 up by 120 mV. I watched it carefully. Stuck the landing. Now, all 24 cells were within 15 mV of each other. Some time on charge took care of the rest.
A couple of errands on Thursday, and I felt comfortable making the six-mile trip over to the Museum. (Plan B was trailering. I left plenty of time so I could get back to the house and get the flat-bed. Don't want to be late for the kids!)
It was a lovely day! I am always impressed by the staff at TDM, and grateful to be in their wonderful orbit.
Time to revisit the "stuff I should do"
list:
- cooling fan for the motor - yes, now that it's
getting warmer. I might do some kind of air scoop
- instrument gauge for the X1 controller (ordered) - turns
out it was incompatible. They were good about giving me
a full refund, etc.
- transmission oil check and, if needed, easy way to
check/fill - checked and topped-up twice. I measured
amounts; It's a slow leak. I still want to make some
kind of a sight-glass setup
- current-measurement rectifier (so you can see regen!) -
can't do with a simple rectifier as the voltage is too
low to forward-bias a diode. I have an old Triplett
meter, though, that swings both ways (so to speak) that
has the same 2" mounting diameter
- main-pack connection to "fuel gauge" (only the 12v
is connectable rn) - done, and nicely, too, I might
add. I put a little multi-turn pot on the wire so that
you can tune the output to the meter
- rear bumper and sheet metal from Eddie - been in
touch!
- badges - need speed nuts/clips; gotta replace the
front panel "latch" with something more sophisticated
- 3D print headlight trims - done, and they're pretty
good. Need to prime, sand, prime, paint
- more data on power consumption - still adding data
in the book
and, in other news,
- got new seat upholstery from misterfiat in
GA. Nice! Done the backs temporarily. Work in progress.
- fixed the front right blinker.
- lubed up the turn signal mechanism on the stalk,
solidified the ground.
- speaking with Nicolas C in France about a couple of
parts, He's going to sell me a roof frame. Need one,
because last Sunday morning, for Cars and Coffee at The
Hut in Sudbury, I got rained on pretty good.
- still need to replace one wheel hub; the stainless
hubcap won't latch
-
At Cars and Coffee, The Hut, in Sudbury, May 2026. Rainy start when no rain was in the forecast, but it was a great turnout and, it seems, the inaugural monthly event!
It's so great to have the car up and running. I'm savoring.