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Messages - BruceM

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Listeroid Engines / Re: Import of Listeroids - Food for thought
« on: January 22, 2022, 03:11:13 PM »
I tend to digress.  Thanks Butch for the clear eyed assessment.
I think the India parts for Lister CS types will continue to make them viable working engines for a long time. 

Listeroid Engines / Re: Import of Listeroids - Food for thought
« on: January 22, 2022, 07:31:12 AM »
Don't hold your breath.  Mark Cherry came up with a method of using a low compression platinum wire catalyst "smart plug" and then proved that high water alcohol fuels could even be burned with it. They burn at a lower temperature and thus have virtually no nitrous oxides or other pollutants.  He called it smartplugs.

He got no takers but a Darpa one fuels forward program funding for some work.
There was zero interest in his development by any engine manufacturer.
I built a version based on his patent for a 2 hp Honda 4 cycle outboard I converted to run on methanol, for my West Wight Potter sailboat. It allowed me to remove the magneto/spark system and just use a 2V battery for starting only.  I had to modify the carburetor and raise the compression, but with that, it ran quite well.  Methanol takes about twice the fuel flow volume for the same power as gasoline. 

Mark's work with high water content alcohol and other fuels used a modest current to heat the platinum element.  He also used that DC current to the platinum elements in later work to provide ignition advance for acceleration. 

A good idea, even with working hardware, independent test data, etc. was not enough to overcome institutional resistance to change.  Concern about pollution is only a marketing game. 
There's zero chance the EPA will let non-compliant diesel engines be sold as alcohol only burners. 

Everything else / Re: Generator Enclosures
« on: January 21, 2022, 09:24:29 PM »
+1  A serpentine or folded air path with carpet or foam or acoustic absorbing materials is common to may successful sound control enclosures I've seen for industrial applications.  Sound pressure waves can only propagate well around the blocked direct path by bouncing, so this greatly reduces the area and improves the effectiveness of the sound absorbent materials.  Serpentine is highly effective as it spreads the sound wave energy in many directions as it reflects from the curved wall.

General Discussion / Re: one of the early members has gone to the lord
« on: January 19, 2022, 04:12:00 AM »
I only knew Quin from his early Listeroid rebuild pioneering and posts.  They were always something I enjoyed and appreciated as a retired engineer (EE/CS).  He was exceptionally capable and wrote like a professional.  After reading his obituary I  wish I'd been able to meet him and know him better.  Quin had some serious breadth and depth of knowledge.
I'm saddened that his retirement was way, way too short.

Everything else / Re: Lithium cell balancing
« on: January 09, 2022, 06:14:08 PM »
Thanks for that link, Tanman. 

It seems the Leaf modules are 2 series by 2 parallel cells , so he's reconfigured at the module level to a 48V nominal system, so roughly 7 modules in series.  Getting to use the intact modules is a big help.  Apparently the other batteries he's using have similar low voltage modules.  Leaf modules are designed to be connected to a BMS and I have found other efforts to replace that BMS.  The lack of cell level BMS and poor thermal management caused LOTS of Leaf battery failures, thus lots of used ones for sale.

It's very surprising to me that he's found the cells exceptionally well matched after 48 months with zero balancing other than the full voltage limiting by the PV charge regulator at the 7 series module level.  He is fuse limiting each 48V string to 30 amps or 1440 W; he mentions that for his system, 10 amp fuses would be sufficient, so he's only charge/discharging at below 10A or 480W per pack.

I agree with Will Proust on this.  He's a young enthusiast, not an engineer,  but his technical information is usually quite good.  His website is also a good resource for those interested in learning about and using Lithium batteries.

I think most non-EE, non-electronics savy folks would be better served with the packaged 48 or 24V battery systems being sold for server racks.  Proust has some good evaluation videos on them.

For safety I'd sure want cell level high/low voltage monitoring and disconnect protection; and with that usually comes some sort of low current passive balancing.   If you don't have cell level voltage monitoring, when one of set of parallel cells dies as a short (which seems the most common reported failure mode), all the other cells in the 7 module (14 cell pairs) series string will be overcharged and this can lead to a thermal runaway and fire with lithium ion cells. 

It is encouraging that some of the automotive packs are designed with low voltage modules. Once LFP (greatly reduced fire hazard) automotive modules/blades are more available, at good prices,  it might be something I'd be willing to switch to. 

Best Wishes,



Everything else / Re: Lithium cell balancing
« on: January 09, 2022, 08:33:18 AM »
This video is unfortunately lacking in legitimate technical information, nothing about what he's doing for BMS/cell balancing, or how he divided up the high voltage packs.  Seems he's set up for a nominal 48V inverter/battery bank, but that's not clearly presented either.  He states he has only put this battery bank together a week ago; so has zero meaningful experience.

His diagram showing Volt and other battery packs in parallel is wildly misleading- the stock packs are high voltage and must therefor be reconfigured to a nominal 48V, if that is what his Magnum inverter is designed for.  I don't know the voltage of the stock battery sub-assemblies of cells are; he has left out all the useful information.

Everything else / Re: Lead acid battery bank confusion
« on: January 09, 2022, 12:26:26 AM »
Reconfiguring the cells for a 24V or 48V setup should be an interesting project.   I look forward to seeing your progress!

There are some decent, inexpensive add on BMS/balancer  systems available.  I'd suggest doing that.  Cheap insurance since the Lithium ion cells are ruined permanently with over/undervoltage. The BMS would disconnect charging on single cell overvoltage, disconnect load with single cell undervoltage.  Important for fire protection as well. 

One gotcha to avoid;if you use a cheap MPPT PV regulator that is buck converting from a high voltage PV array, it is wise to use either a BMS with voltage rating above the PV voltage, or add an overvoltage crowbar or disconnect to prevent a failed PV regulator from connecting the PV high voltage to the battery's BMS.  The MOSFETs in the PV regulator normally fail shorted from input to output, and in a buck converter that means it's a full on. This causes an overvoltage failure, full on short of the BMS overvoltage disconnect so full PV power was connected to the battery.  This is not conjecture on my part, but a reported failure including photos, with a brand new lithium pack worth over $5K destroyed.  The alternative solution is to limit PV voltage to the rated max voltage of the BMS disconnect.

Everything else / Re: Lead acid battery bank confusion
« on: January 07, 2022, 05:23:33 PM »
Hi Tanman,
I'm not familiar with the Prius Plus battery packs and their BMS, but note that they are high voltage (>200V)  batteries that could not be directly used with standard off grid 24 or 48V input inverters and PV charge regulators.

Have you found a home power system that is directly compatible and interfaces to the BMS system so you can monitor battery pack health and balance?  Rebuilding a new battery with the old cells to make a lower voltage battery with a new BMS would be possible but is a significant technical effort.

Lithium Iron Phosphate batteries are more appealing to me due to much better fire safety.  There are some server rack LFP battery systems that are more home power system suitable; they have a built in BMS and are directly compatible with 24 or 48V input inverters and PV charge regulators.

Best Wishes,

Listeroid Engines / Re: 18/1 build up
« on: January 03, 2022, 06:00:45 AM »
Great build, thanks for bringing us along, Butch!
It's a monster but makes sense to me than a twin CS if you need a bit more juice than an 8/1 can swing.

Listeroid Engines / Re: reluctant to start
« on: December 31, 2021, 04:28:44 AM »
Glad you got her going with some savy heroics, Hugh. Well done, and no ether.  I'm a glow plug fan myself.
I did try some 5W-30 synthetic oil one winter; it made a big difference in cranking speed, and hand crank force required when the temps got to -17C.  I ran enough hours then to warrant a thinner winter oil.

I'm forecast for a couple nights around 0F (-18C) in a few days.  With luck it will be sunny and I won't have to start the Listeroid.  I used it this cloudy morning for laundry, it did a remote start without complaint.  At 0 F, I must walk over the hill and unstrap the air compressor and ST-3 and start it bare to warm up, then restart with belts on. The glow plug is a big help in cold weather.  The GAST 4AM with rubber roller just doesn't have the torque needed for cranking at 0F with the air compressor is a 3 cylinder model and is very stuff at 0F. 


Lister Based Generators / Re: Help with 41.25 KVA Lister generator
« on: December 29, 2021, 06:03:04 AM »
Good point, Mihit, he didn't mention any load and I missed that. 

Generators / Re: 5 KW "ST" acting up & down
« on: December 26, 2021, 10:24:33 PM »
+1, Its a genset rpm variation. Intermittent belt slip might also also be a cause of the frequency change. 
The ST head with stock harmonic excitation will vary voltage with rpm change. 

You will sometimes get bogus frequency readings from an ST head due to the "harmonic hump" distortion of the waveform caused by the harmonic winding in the single phase ST heads.  It will show as a frequency way, way off from 60Hz nominal so is quite unlikely in your case, Steve.  It varies wildly between units.  Another good reason to have one of the cheap hand held digital oscilloscopes in your tool kit.  Seeing a waveform can really help with troubleshooting all kinds of things.

Best Wishes,

General Discussion / Re: Would this work ?
« on: December 26, 2021, 06:04:28 PM »
Yes, I adjust welding current with a massive strip resistor made from cut galvanized steel.   I use a big  gapped 1000W toroidal transformer core choke as an arc stabilizer, which helps greatly.

It works great in warm weather but in winter, the batteries output is a bit low and I'm running too cold a weld unless I warm them first.  In summer it will do 1/8 rods in 6013, or 3/32 7018. I can weld thin wall steel (1/16) with 1/16" diameter 6013 rods, but it is very tricky to maintain an arc and avoid burn through.

I'm interested in experimenting with TIG with the same gear,  but my health has been poor so I've put that on hold.  My though was that direct DC TIG with argon would be better for me- less fumes than the coated rods, assuming I can maintain a steady DC arc.   DC TIG welding of aluminum is possible with Helium.

General Discussion / Re: Would this work ?
« on: December 26, 2021, 01:10:19 AM »
I concur with Cobadog; as long as the smart battery charges (switching power supplies) are isolated type supplies, then yes, each can charge batteries that are connected in series. An isolated supply (aka transformer isolated) means it acts like a separate power source, like a separate battery.  It does not matter that the battery being charged may be at some elevated DC voltage relative to earth.

I use 3 smart chargers to charge my direct battery powered DC stick welder.  It uses 3 batteries in series, 2 are 12V, one 6V. The 6V is golf cart type, much larger capacity and a much higher (2A) float current.  The three smart chargers connect with the batteries still connected together in series.  It works fine.  It also trickle charges just fine on three small linear power supplies that I run whenever I've got my main battery bank inverter on.  Again, the trick being to have transformer isolated supplies so each can float to the right voltage level relative to the others.  Just for a thought experiment, if I was to take the welder ground cable, and connect that to the +120V battery bank, they will all still charge just the same as they would when either grounded at some point or floating (no earth reference at all).  This is a bit of a head bender, but if you work with transformers or batteries a lot you get used to it.  Some experimenting with small batteries and chargers on the bench will help.  Even if the battery is negative relative to ground, it works.  So "it's all relative" applies here.

You can also do the same thing with PV, though with lots of copper wire cost and some losses.  For example, you can charge four 12V batteries in series (48V) with four 12V PV panels, and 4 PV charge controllers.  The batteries could be different sizes and types, and as long as you don't use more amp hours than the smallest can safely handle, it will work fine.

With higher voltage strings, it becomes impractical to manage the number of charge current carrying wires and chargers.  The Rudman type shunt regulator design approach then becomes appealing since it lets you charge similar batteries in series with a single charger.

I hope this helps.

Best Wishes,

Everything else / Re: Lead acid battery bank confusion
« on: December 25, 2021, 06:38:56 PM »
Hi Scott,
I stand corrected.
In the attachment I see the method of reducing charge current to less than 1 amp via insertion of a 150W bulb in series, triggered by a 120VAC powered night light sensor to switch in a 150W light bulb in series with the DC charging to limit current when a battery regulator is lighting up. For higher DC voltages this least expensive via a solid state, DC relay or a low side MOSFET switch triggered by a photodetector in this case.  They have two 5V, 5W zeners in series on each 12V regulator, which increases doubles the shunt current capacity to 10W, with the lamps acting as both current indicator and current limiter.  Crude but effective.  If you wanted this to work with the inverter is off or fails, then an alternate circuit for light detection should be used.  It is a rather novel means of opto isolation without using an opto isolator IC.

The light level to trigger the night light will be critical, and it is an all or nothing switch to very low charge current, which will cause an on/off oscillation when there is a  load say half the PV capacity being applied while charging, but for a simple demo it will work, with some care about stray light and visibility of each regulators light to the night light. 

This is the essence of how the Rudman type battery shunt regulators work- the regulator signals for current reduction when the battery is being regulated. 

I hope Tanman will accept my apology for highjacking his thread, and I hope he gets his battery situation sorted out.

Best Wishes.

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