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My fix for Listeroid light flicker

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Yes, it's cheaper to buy your own cells, cheaper yet if you get seconds or derated used cells.

The price I gave is an estimate  for a good priced, prebuilt 100AH 12V battery. 

Will Prouse keeps reviewing cells, BMS units, prebuilt batteries, rack mount setups.

While a young enthusiast, and thus optimistic on new technology reliability and longevity, his reviews and material are technically competent.


Very neat looking research facility

After scouring the Web regarding light flicker with generators, I can see that this is a VERY common issue.
As BruceM noted, the majority of these issues are from using LED lights which are very sensitive to tiny changes in supply frequency.
Regarding engine speed and the number of cylinders, I did not seem to matter.
I found many articles where 3600 rpm screamers were still causing lights to flicker. But again, most cases were when the user had LED bulbs installed.
In other examples, 2 and 3 cylinder Kubota's were involved in flickering lights.
So, before you go changing voltage regulators, generator heads, and engine speeds, first try swapping out LED's for standard incandescent bulbs.

What about appliances such as modern gas furnaces with low voltage DC control boards, or Televisions and Computers?
Are most of these appliances immune to high frequency fluctuations in Hz because they rectify to DC and their DC voltage regulators can smooth out the ripple ?

Note: What I mean by high frequency fluctuations in Hz is the frequency bouncing between say 58hz and 61hz  5 times per second due to 650 rpm Lister power strokes.
          Perhaps enough to mess up an LED, but does it matter to appliances with DC control boards?


most of the appliances, tv's and such have switch mode power supplies that can take in a wide variety of voltages. they then rectify, chop up and transform to some higher voltage, transform and rectify to whatever voltage(s) their design calls for,  so unless the incoming waveform is outside what they have designed to accept, they do a good job of making it work for their uses.

if i had an issue with flicker, i might consider strapping on an alternator, and a battery, and then feed a small inverter, large enough to cover my lighting and sensitive to flicker loads.

or i might use a step down transformer to bring the st head voltage down to something in the 12 or 24volt nominal range (rectified) and feed that into an inverter to output to my flicker sensitive loads.

another option would be to see if i could feed the st power into a ups such as an old apc unit, the output of which is steady clean pure sine wave that could certainly power any flicker sensitive loads.

all of these options have their level of complication, and their attendant loss of efficiency, but some are good enough to consider.  taking a 10% hit in efficiency on relative light loads, such as lighting might not really be much to be concerned with?  certainly less than taking the same 10% hit on heavier loads?

i mean i wouldn't think of trying to do such a system for motor loads, or resistive loads, that generally have no issues with flicker.

all this based on my wanting or having to use a single cylinder and st head,

if i were to design a unit based on the flicker issues, i might start with a clean sheet approach and maybe start out with a different approach to the problem all together.

bob g

Hey Veggie, Incandescent bulbs have heat persistence of the tungsten elements-  more with higher wattage as its thicker wire.  This is why larger wattage incandescent bulbs have less flicker.  My mains and fast reacting AVR are OK on 250 watt incandescent heat lamps but 60 watt incandescent bulbs are still bothersome to me. 

Some  LED bulbs have a regulated switching power supply in the base which will eliminate flicker IF there is adequate capacitance to store some excess energy to ride through the lows; thus some electronic persistence as there is virtually no persistence of the LEDs.  The problem is that the space is so tight that adding capacitance is hard to do.  So what we mostly get are minimalist LED bulb electronics designs that work adequately on grid power or inverters but have visible flicker on generator power.

I found some LED bulbs with SMPS in the base (I took them apart.) with full SMPS that operate well on my 120VDC (126 to 146VDC). I suspect they would not show any flicker on generator power.   I didn't use them as I couldn't tolerate the quality of light or the radiated emissions.  Alas, I just looked and cannot find them in my shop.  I think it was an older Phillips design.  Avoid any LED bulb which is marketed as "dimmer compatible" for generator power as that is going to be a flicker monster. 

With a bit of effort in finding a model of LED bulb with a true SMPS in the base,  it should pretty much eliminate the flicker on generator problem for those who tolerate the unnatural light spectrum of glowing phosphor (white LEDs are really miniature fluorescent lights; they have a dab of phosphor over a UV LED.

Bob, I concur, starting from scratch is the best way. Much efficiency, simplicity, and reduced home power EMI can be gained by having a single high quality SMPS for providing regulated DC to all home/office lighting fixtures.  You can even use some of the stock cheapo LED bulbs; some will often operate on say 160VDC or other DC voltage.  This gets you the advantage of eliminating regulating circuitry in bulbs, a common failure point, and allows for the best energy efficiency.
A couple companies in the US promote such systems for commercial/office lighting systems, but I don't think its really caught on. 

I expect most LED bulb power electronics are operating below 75% efficiency, and have 0.6 or below power factor.  The single regulated DC supply for all lighting addresses approach that, and of course would also eliminate generator flicker.



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