Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.

Messages - BruceM

Pages: [1] 2 3 ... 199
Petteroids / Re: PETTER - PAZ1 - New project
« on: June 14, 2024, 01:02:20 AM »
What a beautiful photo of your recently restored engines! 
I look forward to seeing your progress on the 50cc motorcycle as well.
Best Wishes,

Listeroid Engines / Re: Hot Water Circulator Max Temp Rating.
« on: June 02, 2024, 06:08:57 PM »
 Powder Monkey has an ideal, keep it simple application for thermosiphon tank cooling in that he is running 8 hrs a day in a no-freeze location.  No antifreeze needed and the long time for getting up to temperature and potential increased carbon build up are not a problem for his application.

My application was for short runs, typically 30 minutes. (Pump water while running washing machine, or pump air for the shop, or a 30 minute bulk charge of my battery bank.)   I also have the issue of sub zero temperatures in winter which also make the tank method a poor choice ($) as ajaffa1 wisely notes.  I opted for the thermostat and a (exhaust induced draft- no fan required) radiator with thermosiphon flow because of my  anticipated short run times and a design goal to not require generator operation when operating the air compressor compressor only.  (I could not find affordable cast iron radiators here in AZ or I would have used one with a thermostat.)  I have further reduced de-coking labor by adding a water/methanol feed system.  I keep waiting for the cold idle knocking sound which used to signal time (at 200-300 hrs) for de-coking but now it never happens. 

The perfect cooling system for the CS is application and location specific.  (And the desires and design goals of the builder/designer.)  XYZer created a lovely portable CS design for thermosiphon and fanless oversized radiator with convection only air flow. Standard automotive style cooling setups with pump and fan can be more compact and lighter weight while also being quite practical and economical.  Cujet's portable twin CS design is one outstanding example.

Best Wishes,
Bruce M

Listeroid Engines / Re: Vibration Sensor prevents Flywheel launch
« on: May 19, 2024, 12:46:02 AM »
A floor mounted, EMT frame with wire mesh cage might be a good solution for my 6/1 setup.
Thanks for the good idea, Cujet.  I hope your move goes smoothly! 

Listeroid Engines / Re: Vibration Sensor prevents Flywheel launch
« on: May 17, 2024, 08:28:00 PM »
I agree, Cujet.  One safety weakness of my engine shed design is the shaft on the IP side which drives the ST-3 is unshielded.  Less of a concern since I mostly do remote starts, but still, the risk of clothes being grabbed by the shaft at a moment of thoughtlessness or instability is something I'd like to correct.  I had a PVC drain pipe with cap cover over it at one time but it was friction fit relying on some electrical tape and didn't work out long term.

I wonder if you or some others have already come up with a nice solution.  Your high quality workmanship is always inspirational!

Everything else / Re: DIY single axis solar "tracker'"
« on: May 17, 2024, 08:09:02 PM »
More photos.

The geometry of the actuator mounts is a bit different for the +60 to -25 degree, SSW facing racks (pre-existing manual seasonal tilt), vs the new +-60 degree "summer" rack.  I prototyped these in wood in my shop to come up with the right geometry, and also to test the Arduino Nano, RTC, and accelerometer modules.  The accelerometer- ADXL345 is adequate in accuracy since a few degrees of error matters little for PV positioning.  I have the software repeatedly re-read and re-position as movement and stopping vibration causes errors.  Still, the hourly repositioning takes only a few seconds.  By not hunting and striving for perfection, the linear actuator life will be hugely extended.  I even intentionally avoid using the actuator's limit switches, since their life is limited as well.

Dark clouds mean nothing to this system-  it always has the panels in a reasonable position, waiting for the sun to peak out.  The overnight position can be whatever you prefer.  I choose a position that is suited for stormy high winds from the SW.  I have not added a very high wind sensor, yet, since that adds something to fail, and I think the existing mechanical design  is good for my situation. One issue I found was that using numbered drills to get very tight tolerance on the actuator pin holes was important to reduce play.

Everything else / DIY single axis solar "tracker'"
« on: May 17, 2024, 07:49:42 PM »
Per Ade's request, here are some photos of my DIY single axis tracked arrays.

I have revised all my racks to (3) 2 inch, 0.10 thickness square tube rails for greater stiffness, having retired my original 800W rack and badly snail trailed 175W solar panels.  It was designed for seasonal tilt only with thinwall 1.5 inch rails and wasn't long enough for the 325 to 355 W surplus or used panels I can get locally for very cheap.

This is all part of my custom inverter upgrade, now with sufficient power to run my 1500W home cooler plus have enough power left over for all my other activities. The cooler works by chilling water for my in floor heat system, and that project was previously reported on here.

Under the solar panels you will see two aluminum boxes.  One of these is the Arduino Nano plus Accelerometer board for panel angle sensing, plus real time clock module and H-bridge board for driving the linear actuator.  The second box is unrelated to the tracker, and shorts out one of the 5 panels when there is excess voltage for the current load.  This pre-voltage regulator allows my simple custom linear PV current regulator to handle the new larger capacity input. The linear PV regulator uses 7 IGBT transistors, each with an op amp current sensing driver to evenly share the total current load.  My battery bank is nominal 125VDC, 10 100ah "marine" (lead calcium) batteries in series. 

The entire tracker system is powered by one very small 12V panel and a small AGM battery which is located 1.5 foot below grade in an 8 inch section of round galvanized duct with cap about 12 inches above grade.  The trackers are timed so that they all do their hourly movement staggered in time a couple minutes apart, keeping the max current demand to about 2 amps.  The real time clocks and tracker program of the Nano with specific data table for the individual array orientation are set via laptop and USB cable.  The manual motor drive cable can be used any time by just unplugging the 4 wire auto trailer plug at the Arduino tracker control box, and plugging in the manual cable.  Once the
Arduino is plugged in it checks current position versus table position for month and time of day, and motors the panel to the proper position.  The real time clock has a lithium cell to keep date and time when 12V power is removed.  As you can see in the photo of the tracker box internals, there is zero custom hardware, it is just wiring up of off the shelf components. There is no heat sink required for the H-bridge controller at the puny power levels (2A of 12V) required.  The Nano board provides the 12V to 5V linear regulation.  While the Nano is sleeping, power draw of the whole thing is < 5ma, if the Nano power indicator LEDs are clipped. 

The PV rack mechanicals are pretty simple and derived from older my seasonal tilt rack design.  I'm using 1/2 brass rods with steel split pins as the unlubed pivot points, with stainless steel washers to reduce pivot drag. Many here are very skilled in practical mechanical design  and will come up with there own solutions.  I am pleased with the results here.  It is very solid and does not bounce in the wind, and easily supports my weight and bouncing on the rack with very little movement.  I did all welding myself with my now 3 12V marine battery DC stick welder (with galvanized sheet strip resistor) and 3/32 6013 rods. It was a challenge but I did get the hang of it. MIG would be much better suited to the 0.10 inch wall square tube. 

At present to develop the data table needed for month, hour and position, I used a solar calculator service online to get the plots of sun azimuth and elevation for my location.  I built a scale model with digital inclinometer, and would set up the sun angle and azimuth pointing to the properly oriented scale solar rack, and then eyeball the best tilt angle of the array, reading the angle from the  inclinometer.  A very tedious process.  I then convert via table the angles to accelerometer units. 
A better solution would be to have a program which does this all for you given rack orientation and range of tilt, GPS coordinates and spits out the actual text data table to be inserted in the Arduino Nano program.  I have not done that as my programming skills are now quite diminished.

Having operated this for about a year, (the summer rack for a bit less) I am quite pleased with the cost, performance and reliability.  One design idea I have is to tilt up a version of the summer rack to say 45 degree inclination (I have a south facing hill handy) to do a "winter rack".  This would add to winter day performance but if the drive was changed to +- 90 degrees via gear motor and chain drive, it could also futher increase sunrise/sunset power all year.

I keep watching battery technology and may someday change to LFP or one of it's successors as prices continue to fall and performance continues to improve. 

Best Wishes,
Bruce M


Listeroid Engines / Re: Vibration Sensor prevents Flywheel launch
« on: May 17, 2024, 05:00:23 PM »
I'll try to collect some photos for this soon. 
One thing to note is that if you either have lots of batteries or are grid tie (grid as battery), tracking makes little economic sense in that there is less power (and time) at lower sun angles. In these cases, ground racks with seasonal tilt (adjusted twice a year) will get you almost as much sun harvest with the simplest, most reliable possible setup.  i used the seasonal tilt method for more than a decade despite being off grid with a modest battery bank.  Because I already had tiltable racks, I was able to experiment with adding single axis tracking on the cheap to my existing racks.

When you are off grid, with a modest battery bank size, it can save fuel and/or battery replacement cost to extend PV direct power (through the battery but no draw on it) to earlier and later in the day.  That is where single axis tracking on a budget can pay off, especially for the non-winter months.  In the month prior and following winter solstice,  well oriented fixed panels will do nearly as well, as the azimuth range of the sun is limited, and the elevation range of useful power is also much restricted.

My two older racks  face SSW.  They now tilt from 60 degrees up from horizontal to -25 degrees from horizonal (northerly) to catch early sun in spring through fall. (This is a central eastern Arizona mountains location.) 

My newest 1700W rack is oriented N-S tilt axis, and tilts from East 60 degrees to West 60 degrees.  This one provides great early, mid and  late day power spring, summer and fall.  +-60 degrees is about the max you can do with a linear actuator...more than that requires a chain or gearbox drive ($).  New 2 inch x 0.1 thick square tube steel plus angle stock and 3 inch x 0.25 angle posts for this was about $550. (Same as seasonal tilt.)  Arduino tracker/and linear actuator about $160. 

For me, this means power for electric cooking, laundry, and power for tools (compressed air or other) much earlier and later in the day, most of the year while having a smaller, cheaper battery bank.  it does not make sense to do this where you have a bigger battery/grid tie.

Bruce M

Listeroid Engines / Re: Vibration Sensor prevents Flywheel launch
« on: May 16, 2024, 01:18:47 AM »
Thanks. Cujet.  I just did an oil change and service and moved the compressor pulley inward 1/4 inch against of the off side gib key. With the new split ring collar now I'm feeling more secure. 

 The Picaxe monitor also shuts down if there is no air compressor or generator load for 10 minutes.  That has been very valuable for my memory problems.

There's now plenty of cheap, useful hardware not for the Arduino that lets you just hook up modules instead of doing your own PCBs.  I did a solar tracking project a year ago using them. I use the Arduino Nano with ADXL345 3 axis accelerometer and DS3231 real time clock module for a recent single axis PV solar "tracker".  Plus a BTS7960 H bridge for controlling a 12V linear actuator. The accelerometer lets you measure the angle of the solar panel, so I have the real time clock wake up the Nano (with LED's removed to save power) every hour, reposition the panel to the designated angle for month and hour, then go back into sleep to save power.  I have 3 single axis tracked PV arrays which have been doing the daily dance for a year now.  Nice to not need any active sun tracking, just a sealed box screwed underneath the rack.  If anyone here needs such a thing I'll make a post about the details. Very cheap and mechanically simple, unlike 2 axis...  I was not a fan of trackers before, but this about $130 per 18 foot rack using this actuator:

Having much more PV power early and late in the day is a nice luxury. It was a fun low budget Arduino Nano project.

Best Wishes,
Bruce M

Everything else / Re: Current limiting device
« on: May 12, 2024, 05:55:02 PM »
Hi Veggie,
I always enjoy your interesting and well done projects!

I do concur with CS6_owner.
Without more info on the system, it is hard to see the value in reducing the draw on the 24v battery to 800 vs 1000W via dropping resistor since roughly half the savings are wasted as heat.  But do drop me a note if you'd like to discuss it in more detail.

If the specific model inverter is doing MPPT, adding a dropping resistor may do the job, but as CS6 points out, you then have added an expensive power eating and heat generating element so that battery draw will still be perhaps 900W while the inverter is stuffing 800W into the grid.  You may also achieve the desired result by adding resistance in the AC output feed, again, depending on the inverter design; it will see line voltage getting too high and may back off- or for some designs may just shut down, thus thwarting your plan.  The specifics of the inverter design matter and it can be hard to find such detailed design info. 

Calculating resistance is as simple as ohms law and there are plenty of online calculators.  The problem is that the specific characteristics of your inverter's mppt circuit or output voltage regulation scheme matter.  You will be at something under 40 amps on the 24v side or under 4 amps if on the 230VAC side. If the MPPT circuitry would cooperate appropriately with a drop of 4V, the R=V/I or 4/40 or 0.1 ohm and the needed wattage is 4x40 or 160W minimum (better 250 to 300W).
Here's and adjustable one ($33 US):


Since there is no guarantee of how this may work out with your inverter I would consider testing with a coil or length of  steel fence wire before popping for a power resistor.  Here's a calculator (select iron):

A battery jumper cable to make the steel fence wire connection will allow adjustment. Plated wire will change the value somewhat.  A milliohm meter would help.   I use both 3/16 mild steel rods and galvanized steel strip resistors as adjustable current limiter for my 36/24V battery powered DC stick and scratch TIG welder.  I used the 3/16 rods for initial testing, good data is available online for mild steel wire resistance.  SInce your 24VDC side is at only 40 amps, not the 160 amps of my stick welder, you should  be fine with roughly 7 foot of 1/16th inch steel wire for brief testing.  One useful trick is to measure the resistance of a longer length, minus the meter lead resistance, so you can get a reasonable estimate for your needed roughly 0.1 ohms. 1/10th of the length that measures 1 ohm, for example.

If I was trying the resistance  on the 230V AC side (roughly 4 amps), and was shooting for say a maximum of 15V rise,  that would put my target resistance at 15V/4A or 3.75 ohms at 60 W (better at least 100W).  Adjustables are handy for this and not hideously expensive.


As CS6_owner points out, choosing an inverter with a programmable set point may be the easier and cheaper solution unless you have the spare time to experiment.  There are microinverters that are designed for 350-400W, 24V nominal solar panels. Perhaps a couple of those in parallel...

Best Wishes,
Bruce M

Lister Based Generators / Re: Time for generators
« on: May 12, 2024, 04:32:49 PM »
The internal wiring appears first rate.  Pity you have to mess with it.  It will be a chore to document well enough to remove and reinstall.  I hope the PVC wire insulation is still in good shape so you won't have to rebuild the wiring harness as well.

Lister Based Generators / Re: Time for generators
« on: May 10, 2024, 05:35:05 PM »
Fantastic work.  I love that old tech three phase head. Readily maintainable, reliable.

I applaud the shrink tube color coding.  I have also found that banding with label maker tape- sometimes with a tab for text has held up very well and makes future repairs easier.  The aggressive acrylic adhesive stays secure, so far for 10 years plus.  I can get 4 lines of text on the 1/2 inch wide yellow tape. No other tape has been able to do that, thus my appreciation for colored shrink tube where the color codes can be added to the wiring diagram.   I am trying to do much better on documentation for my tech projects due to failing memory. 

Thanks for sharing your outstanding work!

Listeroid Engines / Re: Vibration Sensor prevents Flywheel launch
« on: May 01, 2024, 06:51:23 PM »
Low frequency current loop was often used for long distances to teletypes in the earlier computer days.  This one is 5V but would work the same at 3 or 12V drive with the right current limiting resistors. 

I applied it here with opto isolators to avoid problems with lightning caused shifts in DC ground levels between two separately (PV plus 12V battery) powered buildings.  You really want to use either optoisolators or better, fiber optics for long runs.  This is too long for plastic optical fiber, 300 feet is about the practical max for POF.   Mulitmode glass fiber is good to over 1500ft but I didn't want to spend that much (connectors and transmitters/receivers are a bit spendy) where it isn't really needed.

No boost is needed and this loop worked fine with only 5 milliamp current pulses.  I didn't need to go higher (which is what you'd do for better noise immunity). Current loops on twisted pairs are quite immune to common mode noise.  I didn't go faster than 600 baud as this was asynchronous serial - no data clock, and I was NOT using crystal oscillators, just the internal RC oscillators. Soft slow edges at 600 baud also means no EMI. 

Listeroid Engines / Re: Vibration Sensor prevents Flywheel launch
« on: April 28, 2024, 04:20:07 PM »
I think you hit the nail on the head, Bob.  The daily temperature swing here is 30-40F in the high desert of Arizona. My off side gib key is held in by the pulley for the air compressor. The split collar "insurance policy" will go on the generator side as soon as it arrives. 

I hope your new home will be a boon for your and your wife's health and happiness.

Best Wishes,


Listeroid Engines / Vibration Sensor prevents Flywheel launch
« on: April 27, 2024, 05:23:48 PM »
My off grid Listeroid has served me well for 16+ years.  It gets less use now that I have expanded my PV system and designed an ultra low EMI inverter which does almost all the AC power generation now.
It still serves as air compressor when I need more air flow, often combined with the inverter powered air compressor.   

I implemented some serious idiot proofing (I have impairments related to MS and epilepsy.) when I installed it 400 feet over a small hill from my homesite. A site chosen for sound, before I found out about the lovely sound of the CS series which does not need such a distance or a hill.  I added remote starting and shut down, and monitoring of oil (high and low levels), temperature, rpm and vibration. It can still be run entirely manually.  I used the Picaxe 40X2 pin Basic running PIC chips to implement this, which predated the now prevalent Arduino. The control panel in my shop communicates to the Lister engine shed via a couple pairs of a 450 foot run of CAT5 cable, using a simple opto isolated 600 baud asynchronous serial current loop.

Wednesday of this week I was running the Listeroid for some Gast 1UP based yard trimming, and it shut itself down showing a vibration fault.  On inspection, I found the red vibration sensor indicator showing.  The flywheel tapered key was on the floor against the North wall, and the (unloaded) generator side flywheel moved outboard from the engine about 2 inches. The flywheel had rotated on the shaft about 1/4 inch at the key- and this had caused the imbalance before the flywheel walked outboard all the way off the shaft.

This happened after 16+ years of running, and that flywheel key had never been removed.  I had neglected to add a 2" split collar to block the key to this side...something I will be adding later today.

This is the second time that my idiot proofing has paid off.  Once before it caught a low oil situation.

How I missed this key loosening on my monthly service and manual start and why it did so after 20 years is a mystery.  But I'm glad I had been ambitious about monitoring of this remote but highly valued engine.  It could have been a very expensive and dangerous disaster if the flywheel came off the running engine and through the wall of my shed.   

For a vibration sensor I used a surplus industrial mechanical vibration sensor unit that uses a magnet and spring, and have it adjusted to JUST not trip during the normal start up vibration. Cheaper new sensors are available now but this one, bolted to the cylinder just below the head did the job nicely.

Idiot proofing saved this idiot.

Don't trust your flywheel keys.  Put on split collars!

Best Wishes,

Listeroid Engines / Re: Knocking, now what?
« on: February 17, 2024, 03:36:58 AM »
I just got caught up on this thread.  Wow, 38AC sure nailed it.  Bravo on your troubleshooting and persistence, Hugh. So glad it worked out.  I hope you can find a small machine shop nearby who can help with your custom key project.

For Christmas I got myself a cheap TIG torch, filled my former nitrogen bottle with argon and taught myself some beginner level scratch start TIG.  Added a new tap so I could use just 2 batteries plus the sheet metal resistor of my direct battery DC stick welding  TIG likes the lower voltage better.  Tried some silicon bronze brazing with it too- easy and quite fun.  That's what I'd use to build up the top edges of your keys, I think. 

Best Wishes,

Pages: [1] 2 3 ... 199