Using a 555 IC or Electronic Timer to Control Reversing Contactor Assembly.

Thread Starter

james31207

Joined Sep 19, 2018
46
I am considering using a reversing contactor set to switch polarity in a 12V DC circuit to electromagnets (drawing 50 A total), and wonder whether the on/off switches controlling the 2 internal coils in such an assembly, designed to open and close magnetic switches in usual applications (for reversing AC motors etc.), might themselves be controlled using a 555 IC-type timer with a 6 to 12V power source; also meaning that the internal coils would be 6 to 12V DC coils.
 

ArakelTheDragon

Joined Nov 18, 2016
1,264
Whats the voltage and current needed for your device?
"Positive supply of timer555: the guaranteed voltage range of bipolar timers is typically 4.5 to 15 Volts".

In reality it might be lower than "15VDC".

However the current will be a little, so if you want a higher one a bipolar transistor or MOS will be needed.
 

Dobbies

Joined Dec 13, 2017
29
I am considering using a reversing contactor set to switch polarity in a 12V DC circuit to electromagnets (drawing 50 A total), and wonder whether the on/off switches controlling the 2 internal coils in such an assembly, designed to open and close magnetic switches in usual applications (for reversing AC motors etc.), might themselves be controlled using a 555 IC-type timer with a 6 to 12V power source; also meaning that the internal coils would be 6 to 12V DC coils.
Can you provide a schematic of your project, and are you switching the polarity manually or on a timed flip - flop?
 

shortbus

Joined Sep 30, 2009
7,091
I am considering using a reversing contactor set to switch polarity in a 12V DC circuit to electromagnets (drawing 50 A total), and wonder whether the on/off switches controlling the 2 internal coils in such an assembly, designed to open and close magnetic switches in usual applications (for reversing AC motors etc.), might themselves be controlled using a 555 IC-type timer with a 6 to 12V power source; also meaning that the internal coils would be 6 to 12V DC coils.
It still won't do what you're wanting. Reversing contactors have a 'dwell' time that keeps them from switching fast enough for your motor. I still don't understand you, your going to change the way electricity is going to be generated in the world, and can't figure out how to make a reversing H-bridge? Even with all of the circuits from both the makers of the components and the ones both in books and online. Dosen't give me much confidence in your project.
 

MaxHeadRoom

Joined Jul 18, 2013
19,198
One problem you may run into if using a AC motor reversing contactor for a 50a DC load is degradation and arcing of the contacts.
50 amp DC inductive load may produce quite the arc.
Have you considered a solid state option for switching the 50amp?
Max.
 

shortbus

Joined Sep 30, 2009
7,091
Have you considered a solid state option for switching the 50amp?
This is the same guy from a month or so ago. He is making a "helix magnetic generator" The switching is the make the helical magnets turn. His generator coils are inside the helix turning with it and the magnets. By some unexplained reason doing this will both generate electricity and at the same time change the molecular structure of the copper in the coils. If this doesn't seem like enough, the current is AC and this will be used to make HHO(doing so puts both the hydrogen and oxygen gases in the same chamber). But he can't figure out how to make an H-bridge, but will save the planet with his "invention".
 

Thread Starter

james31207

Joined Sep 19, 2018
46
One problem you may run into if using a AC motor reversing contactor for a 50a DC load is degradation and arcing of the contacts.
50 amp DC inductive load may produce quite the arc.
Have you considered a solid state option for switching the 50amp?
Max.
Yeah, I'm gonna use H-Bridges, but wanted to check in with you in particular about the possibility of the reversing contactor you originally suggested. It's not as easy as it seems to people in the electronics trade--which I am not-- for someone in my particular position to acquire a ready-made H-Bridge, but I've found a 'Vincotech' module which should work. Thanks for your interest.
 

Thread Starter

james31207

Joined Sep 19, 2018
46
It still won't do what you're wanting. Reversing contactors have a 'dwell' time that keeps them from switching fast enough for your motor. I still don't understand you, your going to change the way electricity is going to be generated in the world, and can't figure out how to make a reversing H-bridge? Even with all of the circuits from both the makers of the components and the ones both in books and online. Dosen't give me much confidence in your project.
Actually, it's a too rapid switching time which is the problem; since most commercially available H-Bridge modules are intended for motors operating at 5A, with inductance of 1 or 2 mH, a switching time in the microsecond range seems standard. The total inductance in my coils is 15 mH, and I'm reversing 50 A [max.]; which means 100 times the back EMF. Still, I've learned that by applying snubbers and varistors etc., large voltage spikes can be handled; and if I can find somebody who knows how to use a soldering iron on minuscule components, I'm laughing. Right.

Unfortunately, I have no technical experience or know-how in electronics whatsoever; nor to be honest am I very interested in the subject. I am compelled to learn something about it because I need this switch--yes, for my experiment. As far as that goes, while I don't think in traditional terms, I certainly understand the substance of conventional electrical theory; and can correlate the principles of my own hypotheses with it fairly readily; and insofar as it is necessary.

However, I really have very little idea of what the purpose of any AC output from this apparatus might be, but presumably, since DC is far more readily conducted than AC, it would involve some enhancement in AC conductance, which is not inconceivable in view of the structure and configuration of the device; although one can only theorise about that with one's understanding of QED imagined from my extremely radical perspective. And as I've said to you before, I will not be daunted by doubts, more especially those of others, until the possibility of success has been fully exhausted; whatever that takes dude.

Also, if you know of any ready-built H-Bridge modules whose transistors (IGBTs) are rated for say 80A (to be on the safe side), and whatever reversing voltage is required--the one I'm considering is 650V (source-drain)--, with a switching time more like a millisecond than 1/2 a microsecond, I would be very grateful to know about them a.s.a.p. I've looked and looked, and the only product I can find is from 'Vincotech'.
 

Danko

Joined Nov 22, 2017
828
The total inductance in my coils is 15 mH, and I'm reversing 50 A [max.]; which means 100 times the back EMF. Still, I've learned that by applying snubbers and varistors etc., large voltage spikes can be handled; and if I can find somebody who knows how to use a soldering iron on minuscule components, I'm laughing. Right
1. In FET's H-Bridge inductive load never produces voltage spikes, because current of back EMF goes back to power supply through FET's body diodes.
2. Use commercial 120VDC or 240VDC coils, then current will 10 or 20 times lower than with 12VDC coils.
I already told you about it in this #82 post.
3. H-bridge transistors are heating in switching process, therefore switching time should be as low as possible, to prevent overheating.
Change switching time from 100ns to 1ms increases FET's heating 10000 times.
 
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shortbus

Joined Sep 30, 2009
7,091
and if I can find somebody who knows how to use a soldering iron on minuscule components,
Also, if you know of any ready-built H-Bridge modules whose transistors (IGBTs) are rated for say 80A (to be on the safe side), and whatever reversing voltage is required
Well so far you haven't seem to learn that any device that can handle that amperage is going to be "minuscule", your word. Or for that mater that H-bridges for your required level aren't of the shelf. That for that level required you make them. There are many, many available schemes out there both from the manufacturers and hobbyists, but nothing is ever going to be tailor made for "your" application, you have to substitute the final "transistor" again your word.

Unfortunately, I have no technical experience or know-how in electronics whatsoever
But when I have in your first thread said you have no experience you get mad? And for someone that has no experience you make such outlandish claims of what your 'device' is capable of.

You fail to understand the basics of electrical generation, the basic principle that a coil moving in concert/with a permanent magnet will generate NO electricity! This is just a very basic principle that is taught in school science, and by school I don't mean college. Either the magnet has to move past the coil or the coil has to move past the magnet, NOT both of them moving together in the same time frame, like your "experiment" is doing.

To another point of your "experiment", the helical arrangement of the PM's is doing nothing to make your sphere move when you're pulsing the solenoid/coils that you want to pulse. No matter what there inductance value. The only PM's that make a difference to movement are the ones directly in line with your solenoids. And solenoids are what you coils are in electrical terms. The field of those solenoids is pretty much directed at that particular PM it is in line with, there is a 'fringe' magnetic field but it is very negligible at the most.

However, I really have very little idea of what the purpose of any AC output from this apparatus might be, but presumably, since DC is far more readily conducted than AC, it would involve some enhancement in AC conductance, which is not inconceivable in view of the structure and configuration of the device; although one can only theorise about that with one's understanding of QED imagined from my extremely radical perspective. And as I've said to you before, I will not be daunted by doubts, more especially those of others, until the possibility of success has been fully exhausted; whatever that takes dude.
Don't be daunted by me or anyone. That is not my purpose of my criticism. But do some real research and understand the basics of things, before both making a fool of yourself and spending time and money on a doomed "experiment". Like they used to say on the X-files, "the truth is out there", you just need to look and understand.
 

Thread Starter

james31207

Joined Sep 19, 2018
46
Dude.. Can you not see that the winding coil is moving past the EMs constituting the stator; and that this winding is therefore continually exposed to a changing magnetic field arising between those EMs and the rotating helical magnetic core. But I don't want to discuss this with you any more. If you want to understand what I'm saying, you are the one who needs to study. Alright.

Also, the core already rotates 135 degrees; and will rotate fully, easily, once a switch is installed to alternate polarity in these EMs. The switch is the problem, not the rest.
 
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Thread Starter

james31207

Joined Sep 19, 2018
46
1. In FET's H-Bridge inductive load never produces voltage spikes, because current of back EMF goes back to power supply through FET's body diodes.
2. Use commercial 120VDC or 240VDC coils, then current will 10 or 20 times lower than with 12VDC coils.
I already told you about it in this #82 post.
3. H-bridge transistors are heating in switching process, therefore switching time should be as low as possible, to prevent overheating.
Change switching time from 100ns to 1ms increases FET's heating 10000 times.
Yes, I should have noted your suggestion about the PWD13F60 (but was distracted by all the silly kerfuffle about the apparatus itself); and of course I had no idea that FETs behave that way--possibly because they don't.

I note also that it is rated for 8A; so if you will bear with me, I need to know, since neither eBay nor ASCO provides any such information, what the specifications are for these Redhat solenoid coils. If there is less current, then there must be more turns; so, how many? That is, will the magnetic field be at least equal to what I have already. Who knows?

I already have the EMs set up, and they work well with a 12 V DC battery; two parallel circuits, each to 6 EMs wired in parallel, about 8A to each max.--but 40 to 50A through each of those 2 circuits. I would prefer the H-Bridges to control the 2 circuits, but it might be feasible to use more H-Bridges. Somebody suggested that when I still thought I was dealing with 800A!! What an idiot I am eh.
 
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Danko

Joined Nov 22, 2017
828
I need to understand what you mean about these commercial Redhat solenoid coils; that there is less current; bearing in mind that current is required to produce the magnetic field: ampere turns.
These coils have many-many turns of thin wire, because of 120VDC.
They are especially designed for producing maximal magnetic field strength at intended electrical power.
So, all is good with ampere*turns in these coils.
I already have the EMs set up, and they work well with a 12 V DC battery; two parallel circuits, each to 6 EMs wired in parallel, about 8A to each max.
I guess your aim is to receive from your setup only some measurable voltage/current and to study their properties.
Therefore makes sense to lower scale of your setup. It will save your time and money.
Danko dude, I think you might just have made my day. And me prancing about with no clothes on and all.
Who knows, are you emperor with no clotches or ugly duckling?
 
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shortbus

Joined Sep 30, 2009
7,091
Dude.. Can you not see that the winding coil is moving past the EMs constituting the stator; and that this winding is therefore continually exposed to a changing magnetic field arising between those EMs and the rotating helical magnetic core
Then if that is the case all you have is a rotating transformer. So why rotate the secondary? You "blogspot does not say what you just said.

And I still stick by my statement that the only inter action with the permanent magnets on your sphere, are the ones closest to the pulsing coils, the ones on either side are just along for the ride. As you get farther away form the core of the electromagnet the magnetic force weakens.
 
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