Saturday, January 20, 2018

Reverse Engineering the TEC-06 Serial Protocol

When I'm reviewing hardware, I always look around to see what I can find about it on the internet (beyond the 500 pages selling some version or another).  For the TEC-06 I reviewed last week, I came across a helpful hint on BangGood about how to make the non-serial version of the hardware a serial-enabled version - along with some links to the software that talks to it.  Given that (and the tools in my office), I set out to reverse engineer the serial protocol, because, well, it sounded fun.  And a serial enabled battery tester is a handy thing to have around, if you want to do some data analysis or logging.


With a New Year's Day afternoon, I sat down and started hammering on the problem.  A few hours later, it was solved.  I've got the serial protocol totally worked out, spent a bunch of time wrapping my head around some bizarre issues, and figured I'd share the process here, for those who want to undertake some similar proceedings in the future.  I even published the software to talk to it from Linux!

So, if you want to read about some serial protocol reverse engineering starting from not very much, read on!

Saturday, January 13, 2018

TEC-06 Serial Battery Tester Review & Analysis

A few months ago, someone commenting on my TEC-02 review asked what I thought of the TEC-06 tester - and I had nothing useful to offer, because I didn't have one in my office to play with.  But, I do enjoy reviewing small electronics, especially if they're related to batteries!  And this one looks like a nice unit, at least on paper.  It supports up to 15V/3.5A/16W, has two useful operating modes, and is rumored to have serial support, if you sniff about on the proper pins!  And I do enjoy new gizmos!

Well, about $15 on eBay later, I had a shiny new TEC-06 in my hands, ready to play with.


Is it any good?  Yes.  Yes, it is.  Why?  Read on!

Saturday, January 6, 2018

2018 Resolutions

Ah, the New Year's Post.  Resolutions for the new year, because we happen to be at the overflow point in our day numbering around the sun.  By March, we'll remember to write 2018 on checks (other people still use those, right?), and statistically, most of us will have forgotten the resolutions.  But, it's still a tradition, and one I'm going to put to some good use.  I'll call this a bit more "public planning" than "resolutions," because I prefer the first term to the second, but the difference is probably splitting hairs.


I wrote up my thoughts on 2017 last week, and this week builds on those.  Much of what I tried in 2017 worked very well, and I intend to continue working on those things.  So keep reading to see what 2018 might bring!

Saturday, December 30, 2017

2017 Reflections

I ended my 2017 roughly as I started it: On an ancient tractor, moving snow.  But, at this end of the year, the tractor is mine, and I've worked on it enough that it's running quite a bit better!  And I can take pictures of it from above!


Another year, another trip around the sun, and time for more reflections and resolutions.  Since I have more interesting projects going on in my life now, I've decided to break the end of year into two posts - an "end of year reflection" and a "resolutions and plans going forward" post.  This week is the reflections, and next week, to start 2018 off, is resolutions and plans.

Saturday, December 23, 2017

Solar Shed Part 17: More Insulation, and Cutting Foamboard Cleanly

Winter is here - and that means an excuse for more shed insulation!  I've added under-floor foam insulation as well as a nice set of window plugs this winter!


If you're not familiar with my office, I took a Tuff-Shed and insulated it fairly well.  I've got rock wool in the walls and ceiling, plus a complete (and gap taped) layer of 2" foamboard inside that.  Then my walls.  It's well insulated - on top, and in the walls.  But the floor is totally un-insulated (because the shed was delivered whole), and my windows aren't particularly well insulated either - they're double pane windows, which is awesome, but a vinyl framed double pane window is very, very poorly insulated compared to the ~R23 of my walls and ~R30 of my roof.

So, being me, I set out to solve these problems and document how the solutions work - as well as some potential gotchas.

Under the floor is tricky - I only had some small access holes.  I went with a local foam insulation provider to blow foam in.  The window gaps are easier - I can just build myself some nicely insulated plugs.

So, read on to see what I did, and how it's been working!

Saturday, December 16, 2017

Building a Cheap Extended Run Tank for my Kipor/McCulloch Inverter Generator

One of the most interesting things about my solar powered office is that the entire office is a machine, it's a very obvious machine, and I don't have an instruction manual for operation.  It's something I'm learning as I go - and last winter involved an awful lot of learning.

Last winter, I ran my generator a lot, which means I had to refill it a lot.  I learned, early, that I lack a gas can suited to filling my generator.  All the new EPA legal stuff is awful to actually use (seriously, EPA, consistent gas spills on the ground aren't better than some gas vapors in the air), and I tended to make a mess with any can I used, because my generator doesn't let you see the gas level through the strainer, and by the time you can see it, you'll overfill it by the time the nozzle drains.  Annoying, wasteful, and I wanted a better solution for this winter.

An extended run tank solves this problem for the most part, but those kits are seriously expensive - a good chunk of what I paid for my generator.  Forget that.  They're simple enough.  I built mine for about $35 (I had the tank laying around).


Curious?  Keep reading!

Saturday, December 9, 2017

Tesla's $0.07/kWh Megachargers look entirely reasonable!

At the start of last year, I did some back of the envelope math on electric long haul trucks.  And, recently, Tesla announced one.  We don't have exact numbers ("Under 2kWh/mi"), but their numbers are compatible with what I came up with last year (1.43kWh/mi).  I expect they'll come in slightly under that (my money is on 1.3kWh/mi), simply because they don't have significant cooling drag to deal with, and can improve the aerodynamics slightly over a big diesel on that alone.


What I want to talk about this week, though, are the Megachargers.  Which, I assure you, are not the latest enemy for the Power Rangers - or the lastest "Mash all of them together" big robot thing.  They're the devices that will cram 400 miles of range into the trucks - in half an hour.  Oh, and for an energy cost of $0.07/kWh.  For megawatt class charging.  I know my way around power rate schedules, but that's iffy from grid power.  Does it pencil out?  If it doesn't, how can they make it?  How feasible is this, really?  Keep reading to find out!