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 Post subject: Re: Tuning the Motor using the Neon Bulb
PostPosted: Wed Mar 02, 2011 2:45 am 
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oh thanks, I had no idea, I even thought the goal was to discharge the battery in 20 hours, hence the C20

I am now discharging the batteries with the proper resistance, but less than half an hour they are discharged

and another fact, the battery may have 12V, but when we add this charge voltage falls too low, I usually turn on a lamp 6V to achieve an appropriate brightness for the lamp

wishes


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 Post subject: Re: Tuning the Motor using the Neon Bulb
PostPosted: Wed Mar 02, 2011 6:20 am 
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We are off topic here so maybe you should start a new thread in the batteries section.

Yes C20 is about discharging in 20 hours. If you have a 12v 10Ah battery and we want to discharge that in 20 hours we divide 10Ah by 20h to give the discharge rate. That is 0.5 amps.

We then choose a load that will draw 0.5 amps and time how long it takes to discharge. If the battery is in reasonable condition it will discharge in 20 hours + or – 10%.

If there is a big difference there is a problem with the battery.

Lead acid batteries slowly shed material from their plates, if half this material has gone you will have half the capacity. Drawing power at a higher discharge rate will cause more material to be lost.

If you battery has only 1/10th of its rated capacity I would use a smaller amp draw till it recovers as the plates that are working may suffer further damage but for charging I would use the C20 charge rate and drive the voltage as high as it will go when charging.

Can you check the specific gravity of the acid? You may need new acid if it is too low.


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 Post subject: Re: Tuning the Motor using the Neon Bulb
PostPosted: Tue Jun 07, 2011 5:40 am 
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Hi All,
I just joined this group two days ago, great to see a lot of like minded people.

And now my query about a predicament I have.
I have two 120 mm and one 50 mm fan. I modified all of them and got one big and the small one going straight away. The second big fan is causing a headache with the tuning. When it runs it does not generate the radiant energy, hence no neon glow. When it generates some it slows down and stops. I cannot find a sweet spot where it stays running and generates radiant energy.
Did anybody come across something like this?

The small fan runs at 2150 rpm, the big one only at 350 rpm, that is where its sweet spot is. Both working fans produce radiant energy when the fans running they are going considerably slower than their potential full speed which is expected. The pitch changes when entering into the radiant energy generation zone with the potentiometer. I checked this with an oscilloscope sound pitch vs glow vs spikes on the scope. Just wanted to see the correlation.
The strange thing is that the two large fans are identical and both are brand new and I cannot get the second one going with the radiant energy.
Coil resistance of the big fans is 110 Ohms per coil and the small fan is 20 Ohms per coil.
I am happy to report that the two working ones are charging batteries.
Can anyone point me into the right direction with the one which is not working? I may have missed something, but I did the same procedure as with the other two.

ImageImageImageImage


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 Post subject: Re: Tuning the Motor using the Neon Bulb
PostPosted: Tue Jun 07, 2011 12:52 pm 
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Welcome to the group :D

it could be a friction issue, try a spot of oil. does it self oscillate?

The resistance of the windings is quite high, don't be afraid to rewind the stator, it is quite easy.

I had a fan with a similar problem, I had to put light machine oil on it every few days, the resistance was 80 ohms. when i rewound it with thicker wire my input and output went up dramatically making the fan better on larger batteries, it also had a little more torque. The new resistance was 6 ohms.

PS the scope shots are exactly what we would expect.


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 Post subject: Re: Tuning the Motor using the Neon Bulb
PostPosted: Tue Jun 07, 2011 9:49 pm 
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Thank you for the welcoming and the suggestions mbrownn.

I will definitely explore both the lubrication and the rewinding.
Maybe I have done some small damage when I tried to take the fan apart and that is causing some extra friction. That was my first attempt and was not sure how the fan was constructed and I removed the bronze bush so probably it is not perfectly positioned in the plastic housing now, after I pushed it back in.

Just to clarify regarding rewinding 1 cw and 2 ccw per winding, isn't that right? I think I have some #25 and #22 wire handy and I will rewind it with the #25 wire.

Also, I found the sweet spot for the 50mm fan's with potentiometer at 3.09 kOhms and the 120mm fan at 2.795 kOhms. The schematic said 2 kOhms but when I noticed that the brightens was at its maximum at full 2 kOhms setting I put a 2.2 kOhm resistor in series with the trimpot to see if the output can be further improved and it did. At this time I did not hook it up to the scope so I could see how well it can be tuned relying only on the subjective brightness of the neon bulb. After I hooked it up to the scope I fine-tuned it so I would get a balanced highest number of spikes with biggest amplitude and I was watching how the brightness of the neon globe changes with the adjustments. I must say the system can be tuned pretty well relying on the neon globe only.

I just realised that I forgot to write descriptions for the scope images so here they are in order:
1. 50mm fan with charging battery connected (sweet spot at 2150 rpm, 20 Ohms per winding)
2. 50mm fan with charging battery disconnected
3. 120mm fan with charging battery disconnected (sweet spot at 350 rpm, 110 Ohms per winding)
4. 120mm fan with charging battery disconnected - signal zoomed


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 Post subject: Re: Tuning the Motor using the Neon Bulb
PostPosted: Wed Jun 08, 2011 2:16 am 
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when winding the stator, wind the first clockwise and the second CCW third CW and fourth CCW. As for what wire to use, I used #23 on a 5" fan with a large stator. On a 3" computer fan this size was a little too big and was difficult to get started on anything below 12v.

If you use #25 or smaller you could trifler wind it and use two of the windings in parallel as the power coil. This will bring the impedance right down and increase your output.

Low impedance is key to good charging.

When using low impedance power coils you will find you need a lower impedance on your pot, because of this, the power flowing through it goes up and you may burn out a normal pot. I now use wire wound, 2 watt pots, to cope with the power.

You may notice your neon goes bright white, blue or purple in color, when this happens you know you have a lot of radiant and the neon wont last long. placing two neon's in parallel may help.
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 Post subject: Re: Tuning the Motor using the Neon Bulb
PostPosted: Wed Jun 08, 2011 3:00 am 
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Since the 120 mm fan is nearly 5" I will use the #22 for the rewind.

Thanks for the other good pointers. Unfortunately I do not have wire wound trimpot but I have various values of 5W resistors.

Now that you mentioned the colour change of the neon bulb I remember that as I was setting the first fan up there was for a moment a bright white flash from the neon and then went back to its normal blue colour. I am not sure how that burst of energy got there because I wasn't actually adjusting anything when that happened. Have you got any ideas or experience like that?


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 Post subject: Re: Tuning the Motor using the Neon Bulb
PostPosted: Wed Jun 08, 2011 3:07 am 
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sprad001 wrote:
The second big fan is causing a headache with the tuning.
Is that real headache or just expression of problem?

sprad001 wrote:
When it runs it does not generate the radiant energy, hence no neon glow. When it generates some it slows down and stops. I cannot find a sweet spot where it stays running and generates radiant energy.
Why do you want both? From what I know the circuit will work in balance. If you use the radiant, the fan slow down or if the fan do not slow down, the consumption raise.

This is not magical device yet. Unless you can get no change of consumption or fan speed after utilizing the radiant output.

If you want to charge battery, I think you should only care for output and not wether the fan is running or not.


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 Post subject: Re: Tuning the Motor using the Neon Bulb
PostPosted: Thu Jul 21, 2011 9:16 am 
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Greetings.

As far as I know my circuit is done correctly but I have one 'weird' thing with the neon globe. For it to work. In the diagram and the video, the neon globe is connected to E and C of the transistor, while the E is also connected to the one side of the fan coil. Now that globe does not work. Yet if I connect another globe to C and the OTHER side of the same coil linked to E, then the globe glows.

Seems like something is wrong in my circuit but I have no idea what. Yet the fan still spins and the charge side does charge.

Here another weird part happens. On my initial running, I used two 12V 1.3ah batteries that were both fully charged (12.60V). At the same time I used a second 12V 1.3ah battery directly on a standard fan to drain it for later charging. When the standard fan had drained down to 4 V, I stopped the bedini fan. The source battery there had dropped to 8.5V while the charged battery had increased the voltage to 12.74.

So I then placed the 12.74 battery as the source battery and used the standard fan drained battery as the charging battery.

I tested the voltages every hour with the following results:-

initial voltage : Source=12.74 Charging=3.97
(these variances are in relation to starting voltages) while the time is relative to previous time.
25 minutes later S:12.43 (-0.31) C 5.48(+1.51) {Ratio 4.87:1}
1:45 later S:12.35 (-0.39) C:6.45 (+2.48) {R 6.36:1}
1h S:12.28 (-0.46) C:6.75 (+2.77) {R 6.02:1}
1h S:12.22 (-0.52) C:6.96 (2.99) {R 5.75:1}
then things became eratic
over the next six hours, the source battery continued to drop at approximately the same ratio, yet the charging battery jumped up and down in this sequence:- 6.73 7.16 7.38 7.39 7.40 6.87

So it seems that for some obscure reason I am not able to charge the charging battery back up to full capacity, while the original charge did charge it higher than the starting voltage of 12.60.

I removed and checked that both diodes were undamaged as well as the transistor, so my circuit seems unharmed.

Now to me this is very weird. A battery that is charged to 7.40 DROPS within 1 hour to 6.87 yet it had a charge going to it. This is confusing to me.

If anyone can clarrify any of this to me I would appreciate it.

BlueMental.


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 Post subject: Re: Tuning the Motor using the Neon Bulb
PostPosted: Fri Jul 22, 2011 1:38 am 
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Hi, It could be that your neon is defective or there is insufficient voltage to light it, remember it will only light when there is no charging battery connected. when you connect the second neon you are effectively shorting the energy in the coil and diverting it away from the output. If the fan still works you must have the wiring correct, try increasing the resistance on the pot. The optimal output is actually at a low speed, can you hear the coils chirping?

Never drain a lead acid battery down below 11.2v, you will damage it. It sounds to me as if you have gel type batteries from what you describe, if this is the case the battery will not recover without drastic measures and may not recover at all. If the battery will not take a charge on a normal charger I think it is the gel drying out. A last resort is to open the vents on the top of the battery and put a little distilled water in each cell then leave it to stand for a few hours before charging.

The reason you are stuck at 7.4 volts is that 3 cells are not working. It is normal for the battery to read a volt or two higher when just taken off charge and this to drop off over an hour or so.

Good luck with the battery :D


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