Bedini Ferris Wheel Regauging Motor

[Turion]

Ferris Wheel Replication

Here is my replication. This is only a 4' wheel, but uses a bicycle wheel as its main component. Could make it 6', 8' or 10' easily enough simply by increasing the length of the boards. No board would be over 5', which makes it easy to work with. Short video of it just turning on my YouTube channel
YouTube - 11Turion's Channel


"Try Not! Do! Or Do Not. There is no 'Try'!"
Yoda
"All truths are easy to understand once they are discovered; the point is to discover them." Galileo Galilei

[ren]

I have no net at the moment Brian, so I cant upload it. Im on my phone at the moment. But its very simple.

Led in the collector leg of the PNP, going to negative. Emitter to positive, hall triggers base. Think of the LED as a coil and wire it up. Its basically the circuit we are using here but with not complimentary pair. Just the hall, and the signal PNP transistor. When your hall triggers the PNP to fire it will light the LED. You will have to check the voltages on your hall, I have a 24v one so its fine to test with a 12v battery. Since the LED (12v in my case) only passes milliamps its pretty safe, you can use a small PNP transistor.

This is a very basic testing circuit, there would be better ones on the data sheet of the hall you choose. Im sure someone else could put a much better one on.

[Sawt2]

Hi Red.

You can get this circuit running on a trigger coil to start with if you like.

Halls will give you a much better result and allow for adjusting of timing and pulse width on the fly, a very useful tool. The trigger coil works great with the SG but the bipolar circuit works better with a hall imo.

Ive used (and gave John K) the SS43a hall (Allegro) and it works good. Its rated for up to 24v input, though I usually regulate this anyway.

Make sure you read up on halls, especially LATCHING AND NON-LATCHING. You need to figure out which side of the magnet triggers the hall. You can make a simple circuit up with a PNP and a led then run your hall over a magnet to check.

regards

(still no net at home thanks to lightning strike... )

Ren
Would you mind posting a quick drawing of the simple circuit to test a hall sensor
Thank you
Brian

[ren]

would just like to post this for everyone. its from the Potentialtec website. i think it gives a few answers for dummies like me.
It mentions using actual trigger coils, separated for timing. is there anything wrong with doing it this way. Not trying to get off track. Just remember in an EFTV vid John explaining the trigger when wound with the coil, and it firing at 23 degrees. if the halls are to trigger at 23 degrees and the trigger coil fires 23 degrees after TDC then what is the difference? are halls just more precise? we can adjust the "on" time with the dwell of the disk magnets? anything else?
Also not sure if its related at all, but the Earth is tilted on its axis at 23 degrees.

Hi Red.

You can get this circuit running on a trigger coil to start with if you like.

Halls will give you a much better result and allow for adjusting of timing and pulse width on the fly, a very useful tool. The trigger coil works great with the SG but the bipolar circuit works better with a hall imo.

Ive used (and gave John K) the SS43a hall (Allegro) and it works good. Its rated for up to 24v input, though I usually regulate this anyway.

Make sure you read up on halls, especially LATCHING AND NON-LATCHING. You need to figure out which side of the magnet triggers the hall. You can make a simple circuit up with a PNP and a led then run your hall over a magnet to check.

regards

(still no net at home thanks to lightning strike... )

[redrichie]

@all with the component questions. help me here
Doesnt the Potentialtech website carry the required parts? If the Hall is to be quick and sensitive and responsive the BOP should be as low as possible correct? My knowledge on this is only what I researched. But the hall offered at PT has a dash for min BOP, which im understanding to be a virtually non existent Gauss rating. Isnt that what we're looking for? Or would having a little magnetic "reluctance" in the Hall result in a sharper switch involved?
forgive my ignorance on this. Im not sure how much of a difference 40-50 Gauss would make in a application such as this.

[Michael Kishline]

Hall Dwell Arrangment

Hi John
You said:
"I think that the timing wheel magnets are closer than 1 width apart. It's important that the fields can overlap. That way you can get a >50% duty cycle on the hall if you need it

Greetings Vissie,

As you know the flat ferrite discs gives off a toroidal (donut) shape field, so the Hall will catch the edge of the field to set the dwell, and if there is any vertical adjustment on the switch that will also lend to it's precision setting.

This is how it works in my head anyway!

Mike
Merry Christmas to all!

[Mark]

I have the same question as Nvisser. Wont the switch always be on if the field overlaps. Same thing with the 23 DEG past TDC, how can you set your timing to 23 DEG when the magnets are 22.5 degrees apart? You dont have 23 degrees to work with.

IN post #36 JB states the machine is set up to emit between 6.85 to 7.1 HZ and the RPM is between 16.8 to 18. Can someone show me the math on this.

In post #57 JB shows 3 halls and dwell timing. 3 pulses, small, medium and a large one. This is just an illustration of the 3 coils on the bottom, correct, we are not working with 3 halls.

I'm sorry if these question are stupid but I'm really trying to wrap my head around this and am going back thru the whole thread to try and comprehend the function of everything. Please help me out.

Thanks, Mark

[Les_K]

Hi John
You said:
"I think that the timing wheel magnets are closer than 1 width apart. It's important that the fields can overlap. That way you can get a >50% duty cycle on the hall if you need it

Take a look at the data sheets for the hall switches. Pay close attention to the difference between Bi-Polar and Uni_polar. Might clear it up a bit, since the 3020 is a Uni-Polar device this might explain some of the timing.

Les

[Les_K]

Les
Try something like the A1106.
The integrated voltage regulator permits operation from 3.8 to 24 V.
Reverse battery protection
Vissie

Actually I just found that the 3120 has same data sheet as the 3020 But I am going to hold tight till John bedini get's back.

OHS3120U Optek Board Mount Hall Effect / Magnetic Sensors

Les

[phishy]

You are such a brilliant Math magician or has someone else got a better expression?

[rave154]

It charges a 14 500 uF cap up to 25V in 5 sec while drawing 200mA from 13v battery which is not bad compared to the same machine with normal coil, magnets and ssg circuit.

This gives 4.53 Joules in the cap for an expenditure of 13 J from the battery...

= efficiency of 4.53 / 13 = 35%

[david.brown]

[nvisser]

Hi Vissie,

I think that the timing wheel magnets are closer than 1 width apart. It's important that the fields can overlap. That way you can get a >50% duty cycle on the hall if you need it. Have a close look at the pic John B posted of the timing wheel with the red lines drawn on it.
I don't think it will work with using the outer magnets to trigger the hall. The timing wheel magnets should be ceramic discs, not neos. I've found that the fields of the ceramic discs spread out from the disc a little bit, so the hall can trigger before it is physically over the magnet.

Good work with the PCB!


John K.

Hi John
You said:
"I think that the timing wheel magnets are closer than 1 width apart. It's important that the fields can overlap. That way you can get a >50% duty cycle on the hall if you need it

[rave154]

Online Conversion - Watt Calculator

Mike

Well spotted Mike......you are indeed correct ( i had multiplied by the 24 when there is no need )..and the new numbers compute to.....

1,300,000 (FWB ) / 51,840,000 (house) = 1 / 40 (a smidge under 40)

so you would need just under 40 FWB's to power a house for a day

[Michael Kishline]

Online Conversion - Watt Calculator

Mike

I ment 14,400Wh x 3600seconds = 51,840,000Joules/day