trigen control system

[mobile_bob]

well after bread boarding the system and getting the unit to go through the prechecks and
then going through the autostart sequence go from low idle ~1000rpm and then step to 1800rpm
and back again without a hitch i figure it is time to take it from concept to a panel

a couple years back i happened upon some nice control boxes from large genset used on a barge.
they have all the requisite gauges, and were loaded with a bunch of electronics that i decided to strip out
and install my system in its place.

the box is very nice, UL listed and the door is sealed very well

here are some pics of the layout, the lower section of the front cover will be reworked to have an E/stop, and other
switches needed by my system along with a manual override, the mid section now covered with duct tape will have
the LED panel yet to be constructed so that there is a visual indication of what the unit is doing along with fault indicators.

there is an anderson plug to get 12dc into the case, and will also have a db9 connector externally accessible so that i can connect
my laptop and watch the program step through all the possible scenario's, and be able to alter the program on the fly to suit what the end use will be.

i have to rescale the amp meter and the generator voltmeter (2 large gauges up top) the amp meter should be easy with the appropriate current transformer, the voltmeter will take a bit of doing, but i have a plan for that.

inside so far i have the top terminal strips to connect the outside world, the box came with those nice rubber sealed fittings,
below the terminal strip is a 12 + 2 fuse panel, below that are the ISO automotive relays SPDT, and under that is the balmar mc612,
the empty space on the right will have two of the controller relay boards and the two micro controllers will be in the general vicinity
(however i might mount them via the db9 in the front cover, not sure yet).

the gauges are some nice units, the smaller are by VDO and the larger by compton instruments

fun stuff, but boy does it take a lot of time

bob g

[Henry W]

That is a nice panel Bob.I am thing of putting some type of control on the portable kubota genset.
At least an idle selonoid to run the engine at 2000 rpm for start up and a shut down selonoid for key shut down and emergency shut down.

And then I have to think what else it should have. I don't want to put to much it the controls for this setup. I would rather keep the cash for the new permenant CHP project.

Henry

[mobile_bob]

this is the prototype of my engine autostart module, it will do the following (at least)

1. power up self test all systems

2. control glowplug relay, and  preheat times

3. intiate startup, starter motor, water pump/fan relays and other ignition only power requirements

4. set low idle, and high idle speeds

5. power up balmar

6. control refrigeration compressor clutch

7. control st head contactor.

and monitor the logic bus from the master controller which will tell this controller when to start and for how long to run, what to power st head, 48 volt alternators, refer compressor, and in what combinations or proportions.

i like the way i have it set up so far, because i can plug in my usb to serial port to the controller and watch the program execute, and make changes as necessary on the fly down to millisecond level (which is more than good enough for my purposes).

in the pics i have a paper face on the front of the panel, it is only for bench work, the final will be replaced with a transparency
which will have the lettering printed onto it, then it will be sandwiched between the main face and an outer layer of lexan which will form the bezel. this will protect the lettering and give it a nice clean look.  the LED's are countersunk in from the back of the face
so they look like they are part of the face rather than the more common poking through look.

these pictures are a work in progress, the unit has been cycling through the 8 outputs all evening and will continue to do so
for several days while i manhandle and beat on it in an effort to get 'er done and work out the kinks

comments welcome

bob g

[mobile_bob]

more pics

the lettering meaning is only for purposes of spacing, so i can work out the template in openoffice
which turned out to be amazingly easy to do.

the words used likely will be different as will font and maybe color

the name of the unit will occupy the larger part of the face at the top, which should make for a nice finishing touch

bob g

[mobile_bob]

loosely assembled with the face bezel covering the transparency legend/lettering

the picture was taken at an acute angle so that there would be no glare and to limit
the reflection from my camera phone, viewed straight on the lettering lines up well with the
LED indicators.

getting close to mounting in the cabinet, making all the connections, and the fun will begin!

bob g

[mobile_bob]

for those that are interested, a cost breakdown of the materials

1 parallax bs2 microcontroller  25bucks  (bought 10 of them at this price off ebay a couple years back)
they cost about 50 bucks new and is the most expensive part of the system.  there are far less expensive processors
if you either know the programming language or want to learn it, but i find the parallax support and programming to be
very intuitive and easy to learn,, so i would pay 50 bucks for a microcontroller and get excellent support and ease of programming
as the compromise.

1 relay board, this too i got off ebay, at 15 bucks each you get the pc board, all the components, and it takes about an hour to solder
together, including solder iron warm up time, and getting organized to do it,, a second board could be done in about half the time.
in my opinion this is a very good price. the relays (8 of them) can control up to 10amps at 240vac so they can directly control some loads and certainly be used to control whatever load one wishes if they are used to drive larger relay/contactors.

1 micro controller pc board, it is the little bugger with the quarter in the picture, they sell for 5 bucks and come with everything but
the processor, take about 20 minutes to solder together and have an area on the board for prototype work,

the lexan/plexiglass was cheap from the scrap pile at my local plastic's outfit, about 2 bucks if i recall

the programming software is a free download from parallax, the interface cord comes as either a db9 pin serial for connecting to your puter, or as a usb to db9, both available from parallax

so for about 50 bucks i have a controller that can control 8 outputs and read 8 inputs, many of the outputs and inputs can do more than one function depending on programming, so the ability to do some pretty complex things can be accomplished quite easily

the puter can also be used as a link to monitor the controllers function in use, in my case i can see the controller step through the processes i have it programmed to do,, in plain english and not some weird and hard to understand computer language.

once programmed i can sit at the laptop, watch the processes operate and if need be alter the processes on the fly in real time, change the program and reload it into the microcontroller (which takes a few seconds) and continue tweaking it to get the results i want.

many folks have asked "why do you want something so complex?" first of all it is not at all complex once you get into understanding it, and ... in order to get the efficiency possible from a cogenerator, along with accurate control of battery bank charging, cooling, and scheduling/load management this is about the best way to assure everything gets done, day in and day out.

i know me, and i know my family members, if left to do all the load management myself, keep on top of battery charge management, etc,,, there will be days (likely many days) that the unit would be running unnecessarily or days the batteries would
be ran flat. the former is costly now but the latter can be much more expensive later.

fwiw, just thought i would put the info out there for those that might be interested

bob g

[mobile_bob]

if i ever get this system built it will likely be my last

my physical limitations are reigning over me large.

spent a about 3 hours getting this much done and tested, it is the intermediate panel between the controller
and the trigen, still have several components in the lower half to get positioned properly and connected.

i am seriously considering just buying a small condo and saying the hell with it, the mind is still strong but the body is
unwilling to participate.

bob g

[vdubnut62]

Wow! you sure do nice work. If I tried this it would look like Rube Goldberg built it. Or worse.
Ron

[sailawayrb]

Very nicely designed and implemented Bob G.  Some pilots like the new glass displays for annunciation, command and control.  I still like the dials and switches.  Are you sure that you are not an engineer?  

Bob B.

[mobile_bob]

thanks guys for the kind words

no i am sure i am no engineer, i just got to where i can spell it right,,, i think?

there will be a set of toggles on the front panel, to set the system to manual, with an on/off/on momentary switch for glowplug
and start, a switch of turning on the pump/fan, another for the balmar regulator (although i am considering a reostat for backup field
control of the 48volt alternator) and whatever else is necessary to make the system functional in the even the 2012/13 solar flare takes out the control system.

i am definitely getting an appreciation for those that build this sort of thing professionally and just why they get to be so complex, once you get started in design it is so easy to add features on paper and before you know it, it takes on a life of its own.

the problem comes in taking it from paper to hardware, sure is a lot easier to draw a wire than it is to make room, cut, crimp, fit, loom, test and troubleshoot the damn things.

another frustration is poor quality parts, i got another fuse block on order, soon as it gets here this one is going to take flight as far as i can throw the damn thing. its just hard to imagine being able to make something of such poor quality even if you try hard to do so.

hopefully by the weekend i will feel like getting back into the weeds on this project,

bob g

[BioHazard]

I'm starting to wonder if bob isn't a robot. Think about it...has anybody actually seen him?!  I say the chinese government planted him here to sell their engines. 

[mobile_bob]

mwahhahahahaaaa

bob g