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Adjusting voltage

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Ron
 Ron
(@zander)
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Joined: 3 years ago
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@makersmarquee At 0.05A it is highly unlikely but not impossible. Don't forget you could have other people involved that are on a pacemaker, now what happens? Since I still have no idea what it is you are doing it is impossible to be more specific. 

I am still quite confused since your OP suggested that you are doing illusions but an ion generator is for creating ions which we can't see but we do see the spark that creates the ions.

Are you maybe confusing a tesla coil or Van de Graaff generator type of demonstration where you touch the high voltage with one hand and a fluorescent light held in the other hand lights up? I am not positive, but I don't think the ion generator can be used in that way. 

First computer 1959. Retired from my own computer company 2004.
Hardware - Expert in 1401, and 360, fairly knowledge in PC plus numerous MPU's and MCU's
Major Languages - Machine language, 360 Macro Assembler, Intel Assembler, PL/I and PL1, Pascal, Basic, C plus numerous job control and scripting languages.
Sure you can learn to be a programmer, it will take the same amount of time for me to learn to be a Doctor.


   
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robotBuilder
(@robotbuilder)
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@makersmarquee 

... so I can only tell you that the intensity of the static varies depending on the input voltage.

Ok. The "input voltage" I assume is the power supply voltage? So the input voltage to the transformer is lower and thus so to is the transformer output voltage which is some multiple of the input voltage. However the other parts of the circuit may be designed with the assumption of having a fixed power supply of 12 volts.

I can't find an example schematic of a variable output for an ion generator.

Is your application the same as the illusionist link you provided?

In the circuit examples you gave, the 555 generates an alternating voltage required by a transformer.

You might like to read up about electronic transformers.  The power in equals the power out.

Power(watt) = Pressure(volt) X Current(amp)

The other type is a voltage multiplier using diodes and capacitors.

You would probably have to look inside the ion generator to know the exact method used.

I see a hack online that removes a resistor to increase the power of a insect zapper.  Maybe if you have access to the electronics of an ion generator you could drain away some of the power to reduce its output by adding a resistor.

I actually have this insect zapper. Wave it through a cloud of mozzies and they all light up like the stars in the sky. Flies tend to just cook in a cloud of smoke.

The circuit for the zapper can be found here,

https://rimstar.org/science_electronics_projects/cfl_powered_by_electric_fly_swatter_racket_zapper.htm

By the way although I have a basic understanding of electronics I am not a professional so take anything I write with a grain of salt and hope a more knowledgeable person responds.

 


   
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robotBuilder
(@robotbuilder)
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Posted by: @zander

I am not positive, but I don't think the ion generator can be used in that way. 

 

The illusionist link seems to suggest you can.

 

 


   
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(@davee)
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Joined: 3 years ago
Posts: 1671
 

Hi @makersmarquee,

Sorry, my own personal opinion is that while the chance of serious harm for the project you are discussing might be small, it is not zero, and I would recommend you find another project.

Some of the previous discussion, whilst all provided in good faith, about currents and voltages has some major conceptual mistakes. I do not think this is a safe basis for designing equipment that might cause harm. High voltages and currents can be lethal.

---------

Background Information

In the past I have tried to find a reliable, 'recognised' figure for a safe current level, from the potential of electrocution point of view - and I failed. It depends upon too many factors, including time of exposure, and health of victim. So far as I could discover, there is insufficient  data to determine a 'safe' figure --- possibly due to a shortage of volunteers wanting to find out whether x mA will kill them? I seem to recall the only recorded experimental data was based on pigs.

--

Contemporary mains power supplies often include 'trips' with names like RCD (Residual Current Detector) (or RCB for RC Breaker), which are designed to disconnect the power if the current flowing along the 'live' conductor significantly differs from that flowing back along the 'return' conductor, on the assumption that if the currents differ, some must flowing by a different path, potentially through a person. You may have explicitly used such a trip if you have an electric lawn mower or hedgecutter. They are also now usually included in domestic power distribution panels.

A common rating for 'general' domestic RCDs is 30 mA (ie 0.03A) for 30 milliseconds ... that is they MUST trip within 30 ms, if the current flows differ by 30 mA. In higher risk conditions, e.g. wet areas (say by swimming pools or showers), the trip current levels are usually reduced, to perhaps 5 mA.

These current levels are NOT even intended as 'safe' levels ... they appear to be compromise levels that have a 'reasonable' survivability record. As Ron (@zander) points out, a victim may have a pacemaker ... and that is not the only 'red flag' to worry about.

------------

The current and voltage levels discussed previously in this thread, such as "9V supply the Ion Generator runs at 0.05 amps and 0.46 watts" refer to the input power ... whilst the average output power obviously cannot exceed the input power, the instantaneous voltages and currents at the output are completely different.

The output voltage (as stated) may be 10 kV or more. This implies the 'average' continous output current must be small, but the presence of the capacitance on the output (C3 and C4 in the lower diagram) means that charge can be accumulated, and the instantaneous peak current might be appreciable. (Even without those capacitors, these circuits have appreciable stray capacitance.)

If a person only touches the output, and is completely insulated (including no capacitive coupling to ground) from the 'ground' associated with that output, then they should not experience any current flow. The tricky and hence risky bit, is that it can be difficult to be sure that the isolation from ground is complete and effective.

Hence, I would recommend not touching the output!

--------------

In reference to your original question, where you were apparently trying to provide a controllable voltage source, in the region of 9V from (say) a 12V power supply, then Ron and others were correct in suggesting a 'voltage regulator', which for the modest current levels of 50 mA could either be a linear regulator, many of which are available in convenient chip form (e.g. LM317T), or a small buck regulator module. Bill (@dronebot-workshop) has made several videos regarding power supplies, which would be a useful introduction to range of solutions available.

Remember, the 9-12V levels are unlikely to be risky, but the output voltages from the circuits you mentioned, when supplied with that power could be.

Best wishes and please stay safe. Dave


   
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Ron
 Ron
(@zander)
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@robotbuilder If you follow that link, then follow the amazon link mentioned, you will find a device that plugs into a cigarette/power 12vdc adapter and  is called

MarchMore 12V DC TO 110V AC Power Adapter Inventer For Car Outlet

 

but it's actually an Inverter since the other end is a 3-prong 110vac receptacle.

This has NOTHING to do with either an ion generator or an illusionist's static/tesla generator.

The OP is confused in my opinion.

I just noticed this at the end of the article

The design used in the article also has a nasty habit of shocking the bottom of your foot quite frequently.

The device is a Static generator, similar to car ignition coil from the 40's that many of us played with in high school.

I suspect there is a safe version of what the OP wants, but find it at a magician's supply store, not some random internet hacks.

 

First computer 1959. Retired from my own computer company 2004.
Hardware - Expert in 1401, and 360, fairly knowledge in PC plus numerous MPU's and MCU's
Major Languages - Machine language, 360 Macro Assembler, Intel Assembler, PL/I and PL1, Pascal, Basic, C plus numerous job control and scripting languages.
Sure you can learn to be a programmer, it will take the same amount of time for me to learn to be a Doctor.


   
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robotBuilder
(@robotbuilder)
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53 seconds into the video in the link there is a warning:
This device is potentially dangerous.
I show how it is made to educate and entertain, not replicate.

@davee

Some of the previous discussion, whilst all provided in good faith, about currents and voltages has some major conceptual mistakes.

Please let us know what the conceptual faults are. I pointed out I am not a professional just a hobbyist interested in electronic projects and how circuits work I did not give a working circuit.

 

@zander

I suspect there is a safe version of what the OP wants, but find it at a magician's supply store, not some random internet hacks.

@makersmarquee
I agree with the others who I assume have expert knowledge, best leave some circuit designs to the experts who can build in safety features and who know the dangers.


   
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robotBuilder
(@robotbuilder)
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This link has a video animation explanation of how the joule thief/blocking oscillator circuit used in the zapper circuit works which I thought was quite good for those interested in how circuits work.

https://rimstar.org/sdenergy/joule_thief.htm


   
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Ron
 Ron
(@zander)
Father of a miniature Wookie
Joined: 3 years ago
Posts: 6939
 

@robotbuilder I don't think I have ever seen this idea before will need to study it to see if/where it might come in useful.

First computer 1959. Retired from my own computer company 2004.
Hardware - Expert in 1401, and 360, fairly knowledge in PC plus numerous MPU's and MCU's
Major Languages - Machine language, 360 Macro Assembler, Intel Assembler, PL/I and PL1, Pascal, Basic, C plus numerous job control and scripting languages.
Sure you can learn to be a programmer, it will take the same amount of time for me to learn to be a Doctor.


   
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(@davee)
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Hi @robotbuilder,

   My concerns started with the question "is heart failure even possible at .05 amps?"

I correlated this question with the battery power supply details ... . "At 9V supply the Ion Generator runs at 0.05 amps and 0.46 watts"

Clearly a 9V battery power source is unlikely to be a source of concern (with respect to electrical shock/electrocution) in normal handling ... but this suggested the questioner had not understood that the circuit they were discussing might be capable of converting a 'harmless' voltage into something much more sinister, and they were looking at the wrong data to estimate risk. They were also presenting two different circuits side-by-side, without noting the difference in power levels. Furthermore, I didn't see any answers pointing out this discrepancy. All of this suggested a situation in which lack of knowledge and understanding was greatly increasing the risk.

----

The old saying which was still being used in my youth was 'it's the volts that jolts, but the mills that kills'. (Of course 'mills' was short for milliAmps.)

This was largely referring to valve (tube) technlogy that still formed a major part of domestic electronics, where radio receivers and (home use) amplifiers commonly worked at around 250V, whilst TVs and radio transmitters went to considerably higher voltages. Hence, technicians were encouraged to work on a live chassis with one hand behind behind their back, so that when they 'found' a live pin with a stray finger, they would feel a sharp sting, probably cut themselves on a nearby sharp edge as the retracted from the live pin, but stood a reasonable chance of surviving. Whilst this saying lacks exact details, I think it gives an indication that even modest currents, when they are flowing through a person, especially if near a sensitive organ such as heart or brain, can be lethal.

--

Hence, sorry Ron (@zander), I realise your answer was well meaning, and I am sure a lot of people have been exposed to a current flow of 50 mA and survived, but all of the commonplace RCD trips I am aware of, which are designed to minimise electric shock dangers, trip at 30mA or lower. As I said, I have previously done a quick search to find a 'safe value' and the only information I could find stated that there were no reliable studies for humans, so the common practices were based on a limited experience of survivors, one or more studies based on animals, and what could be technically achieved without suffering too many false trips. Furthermore, I note that this trip level is reduced to about 5mA (or less) in circumstances that are more likely to result in that current flowing close to a vital organ. So empirically, I regard these as the 'probably survive but might not' levels.

Remember, these trips are only used as 'last chance' protective measures, following failure of insulation, etc. -- wearing a safety belt in a car will improve your survival chances in a major accident ... but it is best not to have the accident!

------

Finally, you may come across RCD devices, with higher current trip values than 30 mA. This may be because they were fitted a long time ago, when insulation of kettles, washing machines, etc. was so poor that 30 mA gave too many false trips, or it may be because it protecting against a different hazard, typically fire resulting from deterioriating insulation and consequent overheating.

---------

Hope this is reasonably clear and that I have not made too many mistakes, for which I take no responsibility.

Best wishes and stay safe, Dave


   
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Ron
 Ron
(@zander)
Father of a miniature Wookie
Joined: 3 years ago
Posts: 6939
 

@davee Perhaps I misunderstand. RCD devices are NOT required in my country at the entrance panel, only specific circuits near water. I don't know about the OP's country. Also, this is a portable battery-operated device, so no RCD is in the plan. The referenced video warns of the danger. The article linked to says he often gets zapped to some degree.

I think the risk with the proposed device is extremely low, but it isn't zero.

First computer 1959. Retired from my own computer company 2004.
Hardware - Expert in 1401, and 360, fairly knowledge in PC plus numerous MPU's and MCU's
Major Languages - Machine language, 360 Macro Assembler, Intel Assembler, PL/I and PL1, Pascal, Basic, C plus numerous job control and scripting languages.
Sure you can learn to be a programmer, it will take the same amount of time for me to learn to be a Doctor.


   
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(@davee)
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Hi Ron @zander,

 I am obviously influenced by my own country's standards, but I know that they are far from unique. In the UK the domestic distribution panel .. formally called the Consumer Unit, but still often referred to as the 'Fuse Box' which it has superseded, normally has at least two RCDs (or equivalent) inside it, for any new or upgraded installations.

Thus, in a minimal system, each circuit has a MCB (miniture circuit breaker) to protect against overcurrent and each MCB is supplied by one of the two RCDs, which detects any flow of current to 'ground'. Having two RCDs means that at least some circuits remain live when the other RCD trips.

The rules generally say that an existing installation that conformed to a lower earlier requirement a the time of installation can continue to be used, but any significant extension should upgrade the whole system. Hence many houses are not yet to the latest standard. However, at least one RCD has been required on this basis for over 20 years, so very few installations will not have any.

Best wishes, Dave

 


   
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