Belktronix Blog
I created this page with a dual purpose, one of which was to remind me what my day to day duties consist of as a
hardware manufacturer. The other was to give a glimpse to the viewer what's going on here as well. I hope to update it
at least weekly.
6/12/09 Extreme past few days (link below for older blogs) Worked on stabilizing the torque pulley on the dyno (might
need bearings soon). Done with tracking down a timing issue (skew) that was causing problems at higher gen amps
(instability and loosing the torque grip on the generator). Thanks to Rex for helping figure out where the problem was.
Now I can handle all a 500A controller can dish out, that controller is heading out (local split system customer). What a
relief, I was starting to look for other load options but figured that too much progress was made thus far, likely its a bug
somewhere. Reworking the dyno for another BLDC motor wasn't inviting (no motor support plate requiring extensive
work) Onward to more amps, with the 800A controller next in line. I can also test the dual charger during dyno rests.  
Always more to do...time for some rest.
Where's the rest of the blog?
Right here
Thoughts? Ideas? email me here
6/16 Finally some positive results after all this testing. After testing to see if there was a overflow problem in the
micros, and testing various circuit blocks, everything seemed to check out ok. While checking other parts of the
controller, the realization came into view. I accidentally had programed over my golden chip and the skew problem
returned. That caused my generator to loose grip again. Once I re-calibrated the control to the clock, the skew was
back to minimal. I confirmed it with another > 500A dyno run. I changed out the current sensors on the generator
(more power) and rescaled the micro to handle the lower output of the sensors. I got to 700A this afternoon on the
800A controller! I also hooked up the dual charger to the pack, and powered it up for a brief recharge. So more to do,
but progress is being made on the dyno! I'll update the dyno page soon to see its new look. Back to work!
6/17 Sooo close! I got to 750A before I heard the belt skip a tooth (sounds like a bang with a shockwave). I looked
over everything once again, and it looked like the lower pulley on the generator was off. So I shimmed the bottom of
the motor/backplate to try to get it more square with the backplate. I checked the top pulley and it looked real close to
true. The belt got chewed on one side so there's something off I need to fix. I tried to preload the belt with more
tension, but the dreaded pop noise came again, at a lower current. Its reminding me of the limits I faced with the move
around under load and decided to look right and found the load cell support beam was flexing under load! I have to
come up with some sort of brace to transfer the load from the right to the left side, hopefully that will help share the
flexing. I may need to use angle on the right side if that doesn't work. Had a weak battery show up in the pack so that
one was swapped out. I updated the dyno page, albeit briefly.
6/18 Another hot day working on the dyno, in 110F temps. I fabricated a long L bracket to handle the flexing of the
right vertical underneath the torque sensor. Got that all reinstalled in by noon. Got to make a brief run but the belt was
still going to the edge of the torque measuring pulley. When it got to the edge, string was flying as it cut the belt edge
off before I could back off the throttle. I drilled and tapped a hole to allow adjustment on one side of the pulley beam.
trying to guess the numeric loss, I got close enough to be ok with it. I ran it again to high amps (wasn't looking at the
meter, but the dyno structure) I looked down the top of the structure and watched it twist under load. At least I
succeeded getting rid of the beam flex, it just moved into the entire structure. Bummer! More thinking to do...probably
bolt in L plates between the verticals, secured to the backplate. Be sure you bolt these WarP motors down real good!
6/19/09 A few degrees cooler in the shop today, I managed to swap the top and bottom crossbeam sections of the
dyno with rectangular 1x2 tubing to give it better structural support, and it helped lesson the twisting on the center
section. With all that, I still only managed to get to 750+ amps (long enough to see the meter) before the belt did the
dreaded -BANG- noise again. It sends a mechanical shockwave through the air that travels into bone. All this is
starting to have secondary effects, the belt seems to be longer than when I first installed it (much more slack to
remove). I ordered a input currents during charging. More to do...Back to work...  
6/20 FINALLY, a 795A dyno run with the new controller!!! I am now able to test to full current. I think part of the belt
jumping teeth was due to (
top secret info hidden) the belt. I did a brief push with the potbox plunger to the floor and
watched the amps climb up on the fluke without the dreaded -bang- from the belt jumping teeth. I need to finish up the
enclosure (possibly a new case layout with the 24V tap by the heatsink instead of the bottom of the case, and some
need to purchase the high end belt or just get a new one to stretch out. I have a day trip to Nevada today for a visit to
my folks, so I'm planning for more fun when I get back...Starting a web page for the New 800A system
here.
6/21 Today I squeaked in some dyno time and took some data with the Warp 9 and the 800A controller. I'm shy of my
rating (5-10A) so I have a little re-calibrating to do. I updated the Warp DC motors web page to show the dyno results.
The Warp 9 produced OVER 200ft/lbs just shy of 800A! Not at all bad, anybody have a Warp 11 laying around to play
with? I'd like to see what that one would do at the same current. Anyway, I have to re-layout the controller cover and
rescale the current limit. Then its time to get more of these made for existing customers.
6/25 With covers changed out for the new terminal spacings and orientation, both the charger and controller
enclosures are done. Templates for the charger and controller covers were created, along with one for the IGBT /
Diode mounting provisions, speeding heatsink fabrication. After the current limit was re-calibrated on the controller,
another dyno run yielded 830 Amps around 750RPM. On the generator side, it felt the Amp difference and began to
loose grip around 1KRPM. More work to do there, hopefully in a few weeks with the new control system, it will be able
to handle the Warp 9 at any RPM. When time permits, I want to see at what RPM the duty cycle hits max at 500A and
800A. Things will be quiet for a few days while I test out the remaining components for the kit and get the first 800A
system ready for shipment. Parts for the remaining kits in the queue were ordered today. Component prices seem to
generally on the rise with higher volumes dropping lower. Unfortunately, the good pricing tiers are at higher volumes
than I use. Got to go plan out the work schedule for tomorrow.    
6/28 Busy on finishing the build for Rob's system and moving the other ones in the queue along.
Yep, its screaming hot out in the shop! It reached 120F at only 2pm today (left gauge), causing
me to retreat into the lab. I think the birds and bugs are taking the day off, hopefully along with
came back, I nearly burned my hand picking up the socket wrench. Can't imagine working day
after day outside in this heat, there's no relief, even in the shade!
7/7 Can't get a email through to Rob to let him know his 800A system shipped today! Well, hopefully he'll stop by and
see it shipped. Visited a customers EV site today and learned a weak crimp can be like a weak battery. The crimp tools
that come with the crimp lug kits usually don't do that good of a job crimping the wire inside the barrel of the lug. The
better crimp. The second thing I learned is you need at least a voltmeter for the pack in the car, otherwise you really
don't know what is going on with your traction pack. The customer's pack dipped to the LVP threshold in the Vehicle
Integrator, 28V down on a 144V pack. Catching up on paperwork today and planning out the next assembly task.
7/11/09 I forgot what was involved with shipping internationally. I did manage to find an online tool to help with filling out
the NAFTA form so that helped out. I had to make a phone call to their staff to get the proper export code for an
electric vehicle kit. I'm glad someone treaded there before me, so the form was done. I'm segmenting the installation
manual for amp and battery (or cell) specifics, just to get rid of the multi-title usage to make it more user friendly. Also
heatsinks over the next few days to keep the build on track. Building up some sub assemblies to finish out the current
build schedule. More to do!
7/14 Things will get a little quiet on the blog for the next few days as I build up 800A controllers for current customers.
I've managed to transfer some hardware from a larger to a smaller water cooled cold-plate that was built months ago
(only 340A of it) and powered it up in the lab. Passing that brief test, I will try to get some dyno time on it this week to
see how the temps look while pumping amps. The forecast is hot for the week, so shop time will be the am hours.
Plenty to do, so back to work. (I never got to post this due to an emergency trip to Nevada)
7/17 Unfortunately my plans for the last few days came to an abrupt halt with an emergency call Tues evening from my
daughter. She was staying with Grandma and my brother and they just got their food at a local restaurant when my
mom had a seizure. She's back home now from a 2 day stay at the hospital, and I think we may finally have an
explanation for her broken arm that happened in her sleep some months ago. I think that's the only way you can break
something and not immediately feel it. Surprisingly, it wasn't considered at the hospital the first time around, this 2nd
event may have been avoided altogether. My mom had driven them both to the restaurant just 15 minutes earlier!
Hard to imagine if that happened while driving, the outcome may have been much different... Thank God it didn't
happen that way. As you can imagine, I've got a bunch of catching up to do!  
and closing in on the gate drive PCB assemblies, still have to build up the drivers. Have some small order parts to
locate, either the mfgr changed the part number, or is discontinuing it. This occasionally happens when part volumes
aren't high enough to move into ROHS, so they get cut from the product line. I'm hoping this isn't the case, otherwise
things might get difficult finding equivalents. In the optocoupler arena, the specs might be the same (breakdown,
current, gain) but when it comes to switching, things get vastly different. Purchased some additional stock parts to
finish up the build. More to do, but its late, time for some rest.
7/26 Expecting cabling to arrive early this week to finish up the controller build. I hope to be on the dyno by the end of
the week testing 800A controllers and shipping out the first part of the kits to waiting customers. The weather forecast
is grim, with 115F expected for the valley this week, I sure hope they're wrong. PG&E's been loving me with 4&5 tier
billing so I'm testing out an old power saver circuit I built 3 years ago on our furnace blower, its yielding a ~25% power
savings (620W vs 820W). I only have 1, so eventually I need to build more to save some money on the electricity bill
for other AC motor loads. Maybe that too will become a product eventually. More EV stuff to do, back to work.
7/31/09 Power cable arrived, along with more parts. Have internal wiring to complete today and tomorrow, then its time
to do some lab current calibration, then onto the dyno. I found some brackets while at Sandy's electronics in Reno a
few weeks back, and thought I could use these for something... Well, I found out just what to use them on. I had to
rework my gate driver boards, I thought I soldered the brackets on correctly, and they looked good when mounted until
I thought of how to wire it up, the brackets would be in the way! So a bit of rework removing the old brackets, and
getting the new brackets soldered up and its all fine now. More to do, its back to wiring!
8/3 I got 1 800A controller wired up and ready to lab test with 2 more to get wired to this point. I got to try out a
hydraulic lug crimper that I bought recently. It crimps in a hex pattern instead of the other deforming method (D shaped
plunger) that I'm accustomed to. So while it looks a little funny, it looks to be a good crimp. I also started to do the
micro revisions that normally come with building up new hardware. Rerouting wires, making things more streamline
from a production standpoint (including making small tooling). The easier it is to build, the better. Summarizing the
documentation is also part of the plan. Each time I build one up, I make sure all the doc's are up to date, this way I
minimize any chance of error in the process of things. There's more to do, back to work!
8/8 With 3 800A controllers wired up, its time to lab calibrate the current sensors. This test runs them into the stator
coil as a load (practically a short) and setting the max current the controllers can produce at WOT. While running the
water cooled setup the other day on the dyno, the pack had a few batteries tripping LVP after 5 minutes at 340A motor
amps. That pack is over 10 years old (previously used in UPS backup for a few years) so I'll have to swap them out
with a set of 155Ah backup batteries I've got. One more Vehicle Integrator to build up and when the calibration is
complete for these few, its time to start shipping them out. There's more to do, back to work!
8/10/09 Started to get set up for calibrating the controller current on the lab pack, found a battery that was low, so I
started a recharge on it and then on the remaining pack. Since this is a low duty pack, I only have zeners which cap a
few hours of charging I came back to find acid had leaked out. I found the top battery puked and ran down 3 of the
batteries until it puddled on the floor. What a mess, I'm surprised that happened on a fresh AGM. With that cleaned up
and the pack charging again, hopefully it will be done enough to test tomorrow. Back to work!
8/11 After charging the pack for a day, I came in to do some calibration
work, only to find another puddle of acid below the pack. Bummer! I got
busy with the water/baking soda to neutralize the mess. By spraying the
battery tops I was able to locate the leaky ones by the fizzing activity.
While wiping them down I noticed what seemed to be a sparking coming from the battery top (the dark lines just below
the sticker). It looked like something was welding inside cutting through the plastic! I've never seen anything like this! I
Hawker Genesis mounted this way, so I figured it would be ok with these. WRONG! Looks like I can't mount these
vertically. Now I've got to make something horizontal tomorrow AM and get the testing on track. Back to work!