Inquiry about suitability of using an Arduino sensor for my project

Projects General Guidance
21

TomGeorge:

"So you are designing a household standby power system, for how long does your mains power drop out?"

A few days at a time, maximum, usually in severe snow storms or high winds, etc.

However, considering the possibility of an EMP or other type of terrorist attack, where the grid could be down indefinitely, I want the unit to be able to work under those circumstances as well.

Needless to say, the device's electronics and the alternator will be housed in a good Faraday grounded cage. I am aware that some types of household appliances will be destroyed by an EMP attack, if it ever occurs, but resistive heat, hot water heater, incandescent/halogen lights, and hardened appliances, etc. will not.

This device is a "looped supply". By that I mean, the water powered motor (WPM) is a jetted rotating drum, that rotates inside an enclosed sump box and with a rotating shaft drives an external alternator via pulley and belt. This is NOT a free-energy situation, just using old technology in a slightly different way.

The drum has water, from the bottom of the sump box, pumped into it. The jets along the outer edge of the drum cause the drum to rotate. Water pumped into the drum by an electric water pump, which in my case pumps out 40 gallons/minute (16 ft/s) to the drum.

So along with the proposed proportional valve, to control the drums speed below maximum safe speed, there will be an on-off manually adjustable valve that is set to limit/restrict the maximum amount of water flow to the drum, when the alternator has no load or if the pulley belt connecting the WPM and the alternator breaks, etc.

Robin2:

The reason I am not considering running my household on an inverter system, powered by lead-acid batteries, is because of the cost of the batteries, their potential danger, and the frequency of needed battery replacements and the number of needed batteries, if they are going to be treated properly to prevent early battery destruction.

By that I mean, a lead-acid battery should not be discharged at a rate (I am told) faster than 1/20th of its AH rating.

That means, if I were to use 1000 AH deep cycle batteries and observed the 1/20 rule, each battery should only supply a 50 AH rate of discharge to the inverter.

So, to be able to power the "full" 7,200 Watts of inverter power, I would need to have 12 batteries in parallel.

Now, I don't know about you, but for me THAT is NOT a quantity of batteries I can easily afford to purchase on my very limited Social Security income.

With batteries of a lower AH rating it would require even more batteries to supply the full maximum power for the inverter at even greater cost.

PerryBeddington:

"You ask if the output current is controlled by the speed of the alternator shaft. Two answers and one question:

The question is, why do you think this is the case?"

Because I was told, "The amount of power it takes to turn the alternator increases as the current load increases as the battery is being recharged or electronic devices in the vehicle require them. The number of RPMs required to produce 50 watts or 100 watts could be 2000 RPMs yet the engine will be working harder, burning more fuel, to generate 100 watts."

So, to me, that means, that as the load current increases, then the drag on the alternator's shaft increases, causing the motor to have to put out more power (torque) to maintain the same needed 3600 RPM speed of the alternator's shaft.

I am not trying to increase or decrease the speed of the alternator's shaft to "control" the output current, but rather to maintain the 3600 RPM to keep the alternator putting out 120 VAC @ 60 Hz for up to 7200 continuous watts.

I think that as the drag on the alternator's shaft varies as the load requirements vary, then that varying drag will put a corresponding varying drag on the motor's shaft which would vary that motor's speed, which in turn would vary the alternator's speed. Right?

Thus I need to be able to regulate the motor's speed by altering its water input speed to maintain it at the constant 3600 RPM speed needed for the alternator. Right?

"Do you know Ohm's law?"

I am well aware of Ohm's law.

" The load takes whatever current it needs when you apply the appropriate voltage. The alternator does not control the current, the load does."

The alternator does determine the maximum current it is able to put out at 120 VAC @ 60 Hz. Right?

Now for lesser amounts of needed current, then the load draws what it needs. But as it does so, it varies the drag on the alternator's shaft, which in turn, varies the drag on the motor's shaft Right?

Paul__B: Please see answer for Robin2 above.

As I said earlier, I have no prior experience with portable power supply alternator heads, so PLEASE clear up any and all misunderstandings I have as stated in my answers.

Rick

22

Hi,

So, to be able to power the "full" 7,200 Watts of inverter power, I would need to have 12 batteries in parallel.

Can I suggest you forget about the full load and have a regime where during a power outing you only use essential loads.
Have you done an energy audit on your location?

I am not trying to increase or decrease the speed of the alternator's shaft to "control" the output current, but rather to maintain the 3600 RPM to keep the alternator putting out 120 VAC @ 60 Hz for up to 7200 continuous watts.

Do you know about PID control?
What is your electronics, programming, arduino, hardware experience?
Can you post specs/date and a pic of your Alternator please?
How precise do you want the AC frequency?
Do you know why remote area supplies and UPS type backup systems use batteries and DC intermediate power bus?

Thanks.. Tom... :slight_smile:

23

rickinva:
However, considering the possibility of an EMP or other type of terrorist attack,

Don't forget the tinfoil hats

...R

24

"You ask if the output current is controlled by the speed of the alternator shaft. Two answers and one question:

The question is, why do you think this is the case?"

Because I was told, "The amount of power it takes to turn the alternator increases as the current load increases as the battery is being recharged or electronic devices in the vehicle require them. The number of RPMs required to produce 50 watts or 100 watts could be 2000 RPMs yet the engine will be working harder, burning more fuel, to generate 100 watts."

So, to me, that means, that as the load current increases, then the drag on the alternator's shaft increases, causing the motor to have to put out more power (torque) to maintain the same needed 3600 RPM speed of the alternator's shaft.

I am not trying to increase or decrease the speed of the alternator's shaft to "control" the output current, but rather to maintain the 3600 RPM to keep the alternator putting out 120 VAC @ 60 Hz for up to 7200 continuous watts.

I think that as the drag on the alternator's shaft varies as the load requirements vary, then that varying drag will put a corresponding varying drag on the motor's shaft which would vary that motor's speed, which in turn would vary the alternator's speed. Right?

Thus I need to be able to regulate the motor's speed by altering its water input speed to maintain it at the constant 3600 RPM speed needed for the alternator. Right?

"Do you know Ohm's law?"

I am well aware of Ohm's law.

" The load takes whatever current it needs when you apply the appropriate voltage. The alternator does not control the current, the load does."

The alternator does determine the maximum current it is able to put out at 120 VAC @ 60 Hz. Right?

Now for lesser amounts of needed current, then the load draws what it needs. But as it does so, it varies the drag on the alternator's shaft, which in turn, varies the drag on the motor's shaft Right?

That's much clearer, thank you. Yes to everything with one small thing I want to clarify but given your obvious understanding of all the above it's probably a minor point.

The alternator does determine the maximum current it is able to put out at 120 VAC @ 60 Hz. Right

The alternator has a maximum current it can supply, beyond that it will be damaged. Once it reaches that maximum the only way it can reduce the load it supplies is by reducing its output voltage, so any attempt to take it beyond its maximum output current will result in its output voltage being below the intended 120VAC.

25

The drum has water, from the bottom of the sump box, pumped into it. The jets along the outer edge of the drum cause the drum to rotate. Water pumped into the drum by an electric water pump, which in my case pumps out 40 gallons/minute (16 ft/s) to the drum.

I was under the impression this would be powered by a stream or river or some such thing. What will power the pump?

26

Hi,
We need a block diagram of how your alternator impeller is getting its water?

I have asked and still no answer,
What is the head of water that you have available?
What is the flow rate of the water supply?

What are the specs of your alternator, can you post a picture of it and link to specs/data?

Thanks... Tom.... :slight_smile:

27

TomGeorge:

"Do you know about PID control?"

Only what I just Googled and read.

"What is your electronics, programming, arduino, hardware experience?"

Basic electronics knowledge but not well enough to design semi-complex circuits; limited C++ programming knowledge from 20 years ago; new to Arduino, am able to understand Arduino sketch programming to some degree (a beginner); no experience with programming and using Arduino sensor components; able able to follow and wire from a schematics.

"How precise do you want the AC frequency?"

To be able to run 120 VAC 60 Hz electrical devices.

"Do you know why remote area supplies and UPS type backup systems use batteries and DC intermediate power bus?"

Do not know what is meant by "remote area supplies" (unless you mean power sources in remote, off-the-grid places"). UPS units are used primarily for short term emergency power backup switching to enable an orderly shutting down a computer system to prevent data lose from sudden power failure.

As for batteries and DC intermediate power bus, no idea at all.

As for the alternator head proposed:

https://www.ebay.com/itm/Heavy-Duty-10000-Peak-7200-Running-Watts-Belt-Driven-Generator-Head-3600-RPM/253198466575?_trkparms=aid%3D222007%26algo%3DSIM.MBE%26ao%3D1%26asc%3D20131231084308%26meid%3Dde2ef8cd4a064e9dbb080854e90ca331%26pid%3D100010%26rk%3D2%26rkt%3D12%26sd%3D173634078001%26itm%3D253198466575&_trksid=p2047675.c100010.m2109

Robin2:

Make sure you properly ground that tinfoil hat.

I am not worried about Russia, China or North Korea causing an EMP, but I wouldn't bet against the elite creating a limited one somewhere in the US, as another 9/11 type "false flag", to help further their NWO takeover.

I remind you of Matthew 25: 1 - 13.

(But this is totally off-topic.) Sorry.

PerryBebbington:

Sorry for the typo in the spelling of your name earlier.

Yes, I am aware that if the load is greater, than the alternator's designed maximum, it would damage the alternator or equipment connected to it and that is way an overload mechanism to prevent power overload is needed. thus the use of a demand-load circuit breaker; and then the need to prevent over-speed of the WPM to prevent its destruction.

"I was under the impression this would be powered by a stream or river or some such thing. What will power the pump?"

A battery & inverter system. :slight_smile: :slight_smile: :slight_smile: It only needs ≈ 500 Watts of 120 VAC 60 Hz power. One of the uses of the alternator's power would be to recharge the battery, once it is running.

TomGeorge:

The proposed alternator head is as follows:

https://www.ebay.com/itm/Heavy-Duty-10000-Peak-7200-Running-Watts-Belt-Driven-Generator-Head-3600-RPM/253198466575?_trkparms=aid%3D222007%26algo%3DSIM.MBE%26ao%3D1%26asc%3D20131231084308%26meid%3Dde2ef8cd4a064e9dbb080854e90ca331%26pid%3D100010%26rk%3D2%26rkt%3D12%26sd%3D173634078001%26itm%3D253198466575&_trksid=p2047675.c100010.m2109

Any suggestions in what I should ask for when I seek help in designing the needed circuit for the Arduino controlled proportional valve circuit? Especially if some type of PID is the way to go?

Thanks to all of you for your wonderful help.

Rick

28

Sorry for the typo in the spelling of your name earlier.

Thank you, no worries :slight_smile:

"I was under the impression this would be powered by a stream or river or some such thing. What will power the pump?"

A battery & inverter system. :) :) :) It only needs ≈ 500 Watts of 120 VAC 60 Hz power. One of the uses of the alternator's power would be to recharge the battery, once it is running.

So, let me be sure I have this right...

You intend to have a battery powering an inverter which will output about 500W which will power a pump which will feed water into a water powered motor which will drive an alternator with a load up to something over 7kW, some of that 7kW will feed a battery charger charging the same battery that is powering the inverter etc...?

Is that correct?

29

PerryBebbington:
So, let me be sure I have this right...

You intend to have a battery powering an inverter which will output about 500W which will power a pump which will feed water into a water powered motor which will drive an alternator with a load up to something over 7kW, some of that 7kW will feed a battery charger charging the same battery that is powering the inverter etc...?

Is that correct?

Hopefully it is wildly incorrect :slight_smile:

...R

30

Robin2:
Hopefully it is wildly incorrect :slight_smile:

...R

Not if you believe in perpetual motion!

Paul

31

Paul_KD7HB:
Not if you believe in perpetual motion!

See Reply #22 :slight_smile:

...R

32

PerryBebbington:

"Is that correct?"

Yes. Ain't Nature's open systems great! :slight_smile:

Now where and how the needed energy comes from to drive the device is not the subject at hand.

What I am asking for is help/information on whether I can use an Arduino system to control a proportional valve that in turn will control the flow of water into the drum to maintain its speed so that the alternator head will constantly rotate at 3600 RPM when the motor is attached to an alternator with varying loads. Or whether any additional control is even needed for loads lower than the alternator's designed maximum if the motor is set to rotate the alternator at 3600 RPM. The speed the manufacturer says is needed for maximum output of 7200 Watts of 120 VAC @ 60 Hz.

Rick

33

rickinva:
What I am asking for is help/information on whether I can use an Arduino system to control a proportional valve that in turn will control the flow of water into the drum to maintain its speed so that the alternator head will constantly rotate at 3600 RPM when the motor is attached to an alternator with varying loads. Or whether any additional control is even needed for loads lower than the alternator's designed maximum if the motor is set to rotate the alternator at 3600 RPM. The speed the manufacturer says is needed for maximum output of 7200 Watts of 120 VAC @ 60 Hz.

I reckon it is not possible.

...R

34

"Is that correct?"

Yes. Ain't Nature's open systems great! :)

Now where and how the needed energy comes from to drive the device is not the subject at hand.

Well, no, strictly it's not but people on this forum are interested in this kind of stuff and want to know. In any case, if you did get this to work you'd solve the global energy problem and probably get a Nobel prize. You'd certainly get very, very rich.

I'm sure everyone here would love to see this thing when you get it working. Visiting you is probably not practical, but some photos would be very interesting. Are you keeping the source of the missing 6700W secret? Perhaps for your patent application.

35

Robin2:

My bible reference to your comment above was not meant as a religious reference/comment, but rather (using that parable) a quick shorthand (read that as "lazy") way of saying "that although we hope there will never be a wide spread grid destruction and the resulting chaos that will cause, it is better to be prepared for that possibility, than to assume it will never happen, only to be left out in the "dark" because we didn't prepare for it."

I want to apologize for saying what might have looked like a "religious swipe" at your comment. No such meaning was intended. In the future, I will be less lazy and say exactly what I mean. Please forgive the unintended disrespect.

PerryBebbington:

This device has already been made by someone other than me. And for him it works quite well. However, his version provides only a fixed output for fixed loads and that does not lend itself well to varying load situations.

Under his method, if the load varied significantly, the water pressure to the drum would have to be regulated/adjusted by hand, to keep things working correctly, and to prevent runaway self destruction of the drum, especially if the load were to suddenly drop significantly or altogether.

Since standing by the device whenever it is in use to monitor its water speed needs and adjust its limited valve accordingly would be not only inconvenient, but many times not even possible. I am hoping to find a way, by using a proportional valve, to make it more user friendly and useful under significantly varying load swings.

A more complicated process of controlling the water flow, using several NC open/closed directional valves has been "suggested", but that method seems way more complicated than I think should be necessary and its control circuit was also monitoring the alternator's output voltage instead of shaft speed.

So I am investigating the possibility of using a proportional valve instead. But I will need help in designing the control system for it. Thus my request here as to the possibility of using some kind of Arduino sensor and current controlling output circuit and using an the Arduino and a program for it that will be necessary to activate and control the valve as needed.

The "desired" proposed proportional valve is controlled by varying the current to it between 4 and 20 mAs.

I originally thought that as the load on the alternator fluctuated, the voltage output would vary for a given water rate supplied to the drum. That as the load varied, the drag on the alternator's shaft would vary, causing the drag on the motor's output shaft to vary which would affect the drum's speed and thereby the alternator's speed as well. So, I thought I would need to alter the amount of water being pumped into the drum to maintain its rate of speed that in turn would keep the alternator's speed at 3600 RPM to keep the alternator's output constant.

However, it seems, from what I have been told here, that the speed of the alternator's shaft doesn't control its voltage output, only its frequency. That the voltage will be controlled by the alternator's voltage-regulator controlling the current to its rotor's field coil. So, monitoring the alternator's voltage would not be the way to go and so "dave-in-nj's" original suggestion to monitor the alternator's shaft speed instead, along with others suggestion to include overload protection, would be what is needed instead, probably by using a hall effect sensor and control circuit.

Rick

36

rickinva:
My bible reference to your comment

I'm afraid I had not noticed it. In any case I am an atheist.

Referring to your earlier comment about the cost of batteries. yes I am aware that they are expensive (have 400Ah of them myself) but, frankly, I don't think there is a practical alternative.

...R

37

This device has already been made by someone other than me. And for him it works quite well.

Please do report back to us on the success or otherwise of your device.

This unit is to serve as an emergency backup when there is a loss of "mains" power to the home.

If this thing works as you hope and, I assume, produced electricity at little or no cost, why would you even bother with mains electricity?

38

We are totally sidetracked from the purpose of my original question.

I have been told from an earlier comment that I should be able to use an Arduino circuit and program to control a proportional valve based on the speed of the alternator's shaft to keep it rotating at the desired 3600 RPM.

I assume by using a Hall Effect sensor with the Arduino.

So, is there a "premade" Arduino actuator that I can use to control a proportional valve that makes use of a Hall Effect Sensor and Tachometer circuit to track the speed of the alternator's pulley and then adjust a proportional valve, or do I need to make one of my own.

If one is already made which unit do I need to buy and use?

Rick

39

off topic...
If you’re still keen on varying the shaft speed, how about losing the proportional valve, and using a CVT-style transmission from the impeller/drum to the generator shaft...

Simply sliding the transmission across the two ‘cones’ will offer a wide linear range of shaft speed control. The ‘arduino’ could drive a simple servo control of the ratio.

Somewhere in this whole project, you need to consider the wear, reliability and repairability of the mechanical components.

Sounds like fun. Protect your entire power reticulation infrastructure from that nasty EMP, or the generation will be a moot point!

40

lastchancename:

What do I need to look up, read about and study, so I have some idea as to what you are talking about?

At the moment, I don't have the slightest idea, but am open for any suggestions to make the device better.

As for a possible EMP, all parts of the device will be hardened. except for the power output connectors. All else will be encased within the grounded cage. Needless to say other EMP sensitive vulnerable needed devices will be placed in a hardened area also.

Thanks for your suggestion. Now, if you will help me understand what/where I need to learn about it.

Best wishes to all for the New Year.

Rick