Can 3 inverters be used for 3 phase power ?
Can 3 inverters be used for 3 phase power ?
(OP)
I have three inverters and a 10 hp motor and need to know if the three units can be used to supply each leg to the motor, the inverters are modified sine wave units 5000 watt that use 12 volt in and output is 120 volt ac @ 40 amps.
There will be a step up transformer that delivers 240 at 20 amps for each leg.
My question is has anyone tried this and how well did it work?
There will be a step up transformer that delivers 240 at 20 amps for each leg.
My question is has anyone tried this and how well did it work?





RE: Can 3 inverters be used for 3 phase power ?
Have you asked the maker?
RE: Can 3 inverters be used for 3 phase power ?
They would share a common line, but each hot wire would go back to the inverter that generated it.
I have not tried to contact the inverter vender as they are only a supplier in the USA i haven't looked but i'm sure it is manufactured in China or Tiwan.
I know about the frequency issue as i tried to wire two small units togeather, the first time it worked and the next time i saw the smoke.
Thanks for your input
Ron
RE: Can 3 inverters be used for 3 phase power ?
Can you tell us more about your application? Maybe we can suggest something.
RE: Can 3 inverters be used for 3 phase power ?
I have a group of 12 deep cycle batteries that will be wired in parallel for a large amp output.
The three inverters will draw from all batteries at the same time, passing 120 volts thru 5000 watt transformers raising voltage to 240 at about 20 amps each, driving the 10 HP 3 phase motor which turns a 10 KW generator head with a 160 pound flywheel, which will be raised to speed by a 3HP dc motor before engageing the ac supply.
The batteries will recharged from the ac generator.
When this system is up to speed it takes little energy to maintain it's motion, a large load applied has very little drawdown effect on the heavy flywheel.
At this point my goal is to design a cycle that drops a depleted battery out of the group and brings it to full charge before putting it back with the group.
The ideal system would be to have the no.1 battery fully charged as the no.12 battery is at it's design low, and all the batteries in between at various states of charge.
The method for monitoring the batteries can be either electrical or mechanical or a combination of the two.
I have used one inverter/transformer to run a single phase 2HP motor which powered a 5HP compressor and a 225 amp electric welder, but not for an extended period of time.
So far this has been a fun project, and I still have the charging program to work out.
This will eventully grow to a power assist unit for my Ford ranger truck.
Hope this is not too much info
Thanks
Ron
RE: Can 3 inverters be used for 3 phase power ?
Have you considered a VFD? VFD's happily run three phase motors and allow lots of configuration and adjustment. You can run them from single phase power and, derated some, they will create 3 phase power to your motor/s that will run them in a robust manner. You can also provide them with just pure DC. This might allow you to run them with three inverters without the inverters being in phase. Others here with far more VFD knowledge will hop in and advise.
Meanwhile you could run two of your inverter's to provide all the single phase 120 and 240V loads.
Part of the problem with using inverters to run motors directly is that the motors require very large starting currents which can damage your inverters. Whereas the VFDs are built for this service. They aren't as pricey as your inverters either, I bet.
RE: Can 3 inverters be used for 3 phase power ?
The learning never stops, didn't know what a VFD was so i surfed the web and found a post VFD's for dummies. A few other sites talked about using vfd's and even got close to prices but for larger HP units.
If my understanding is close to right, there might be some value to a bank of 20 batteries in series for 240V DC.
One thing to keep in mind is my intended design calls for keeping a 10KW generator/flywheel at rpm at a constant run time equal to the time of doing a job of short duration in most cases.(as in compressing air till the tank is full,short duration welding, or cutting wood with a saw.)The rest of the time it is running at a low amp draw, just enough to stay at rpm while rechargeing one or more but not all of the batteries.
How many times have we seen a construction job in progress with a gas generator that runs all day, and yet only delivers energy to a unit two or three times per hour, if that much.
Having batteries in, singles or multiples of some configuration, would give the ability for always having a fully charged input at most times while one or more are being recharged.
Before anyone mistakes my intentions, the whole system will eventully run down and need an infusion from a source such as gas or the grid.
This brings us back to the point of running a 10HP 3 phase motor from a 12v dc or? battery system. The VFD does sound like a good option.
As i learn more about this item i want to thank anyone in advance that is willing to share their thoughts and experince with me.
Thanks
Ron
RE: Can 3 inverters be used for 3 phase power ?
I don't see any point in having the system continually re-charging a battery. The energy you're going to put into the battery being charged will be drawn from the other batteries draining them. When you add in the losses incurred in the electronics and motors/generator by doing the charging, you'll just be draining the other batteries quicker than if you let everything idle. Also, if you series connect the batteries then you do not want them at different levels of charge.
A motor freewheeling and connected to a VFD output will draw very little power from the batteries. It will only draw the losses of the idle motor.
RE: Can 3 inverters be used for 3 phase power ?
One minor tweak however may be to ut a PV array on your trailer that is recharging the depleted batteries. The recharge rate would be slow, but at least it is an input instead of a depletion.
As to the VFD part of this, you could use a standard VFD and use a voltage doubler system to step up to the right DC level for input (300VDC). That is how you get VFDs that show 120V 1 phase input and 240V 3 phase output. You just have a lot further to go! But if your intent was for that 3 phase output to run just the generator to recharge the batteries, forget it all together.
"Our virtues and our failings are inseparable, like force and matter. When they separate, man is no more." Nikola Tesla
Member, P3
itsmoked (Electrical)
LionelHutz (snigger)
Something like 60% efficient, so you are going to be dumping that 40% of energy every time you start charging them. A truly efficient system would be an auto-start for your generator or one of those inverter generators that idle so quietly they can barely be heard 10 feet away then leap to whatever speed required to supply the required power.
jraef (Electrical)
LOL itsmoked, we must have been typing in tandem!
itsmoked (Electrical)
Yeah!! 

.
Barry1961 (Industrial)
DC to AC inverters are very cheap and plentiful. While they are not very efficient, 85% at full load and 87% at .33 load, they are more efficient than running a generator full time.
Ron14 (Mechanical)
(OP)
Well guys..
itsmoked (Electrical)
Atually it is not at all clear on how you are going to keep your batteries charged... How about a clear statement of how everything is going to hook up. Include any new found info.
Barry1961 (Industrial)
You would probably get a more positive response in a different forum.
Ron14 (Mechanical)
(OP)
You have all been kind enough to respond, so i'll continue as best i can.
itsmoked (Electrical)
Do not forget that you cannot work the entropy backwards. Highly organized electricity cannot be made in a one to one manner from disorganized heat. This is reflected in the heavy efficiency losses in the conversion processes.
Barry1961 (Industrial)
Many people have tried to multiple power or create perpetual motion machines by using flywheels. Many people have spent a great amount of money trying to do it. Some people have made good money selling people kits for free energy machines that the government does not want you to know about.
Ron14 (Mechanical)
(OP)
Thanks for the kindness in nearly all the post, I seem to have let things get out of context, due to my inability to transfer into words my thinking, understanding, and what i am trying to accomplish.
Barry1961 (Industrial)
"As one article in my past studies stated, " pound for pound a flywheel will store 10 times more energy than a lead acid battery" if this is anywhere near accurate it only represents a storage medium."
GregLocock (Automotive)
Energy storage per unit weight for a carbon fibre flywheel running in a vacuum via a 98% efficient motor/generator, would be about the same as a lead acid battery, to within a factor of two either way.
itsmoked (Electrical)
GregLocock I think yur dreaming if you think you can get 98% out of a lead acid system.
GregLocock (Automotive)
Learn to read posts before criticising them.
itsmoked (Electrical)
I'm sorry..
GregLocock (Automotive)
Ooops, oddly enough I've measured it. However I misremembered the number, it is 90%, as the coulombic efficiency is almost 100% but the charge voltage is 2.2V per cell,and discharge is at 2.0. So, sorry, you are right, I was wrong to say 95%, 90% is nearer the mark.
Barry1961 (Industrial)
After thinking about it, a car engine already has two flywheels that probably weigh more than the battery. So if you run the engine at close to the speed the starter motor turns it, very low idle, and then cut off the ignition it should continue to spin for about 10-15 minutes. This test will be cheaper and safer than the one I posted before.
Ron14 (Mechanical)
(OP)
A lot of good questions and comments.
jraef (Electrical)
To me, this original discussion still seems to skirt the edges the first law of thermodynamics, and to my knowledge, that law still stands firm. You cannot get more, or even equal energy out of any system than what you put into it, no matter how many devices you add to the system to try and recover waste.
Read the Eng-Tips Site Policies at FAQ731-376
RE: Can 3 inverters be used for 3 phase power ?
Don't we need ugh 300V of batteries for the pure DC scheme? That's why I was on about using the inverters with rectifiers to come up with the 300V.
Ron14; As Mr.Hutz mentioned you really do want just one bank of batteries. The more you have the more efficient the system will be.
Here's a little ice water for you (sorry). Any batteries will create lousy efficiency.
Alternatively build a trailer scheme that has 300V worth of solar panels (roof) that keeps the 300 Volts of batteries (floor) charged for those moments of work. I would think this would come out just about right. If the solar started to fall behind then a small, regular, generator could auto start and run till the batteries are charged or use shore power.
RE: Can 3 inverters be used for 3 phase power ?
RE: Can 3 inverters be used for 3 phase power ?
Great minds think alike... when they work at all.
I'm glad you touched on the perpetual motion angle. It isn't entirely clear what the OP is up to. I was assuming he isn't up to alchemy. But you never know
RE: Can 3 inverters be used for 3 phase power ?
Remember that a flywheel is a mechanical device for storing energy. You put energy into it and you take energy back out of it. To put energy into it you accelerate it, to take energy out you decelerate it. Maintaining the velocity of the flywheel also takes energy, which is your “loss”.
The key point is that the only way to get energy out of the flywheel is to slow it down. The flywheel will not make your system more efficient unless there is a shock load that is more than the drive can handle.
If an air compressor starts and takes 3 minutes the refill the air tank the flywheel would have to be decelerating for the full 3 minutes to keep putting energy back in. What will happen is that when the compressor first starts, 5 times full load current, the flywheel will help the motor/generator for about one second. After that 1 second is over it will become an additional load on the motor generator.
If the motor/generator can handle the load the rpm will not change much from no load to full load, maybe 1780 rpm to 1750rpm. Adding a flywheel will reduce the drop but will slow down the recovery. And it will take just as much energy to speed the flywheel back up as it took to slow it down.
They flywheel will not help the efficiency of the system you have described at all, period, not, nada, no how and no way.
Barry1961
RE: Can 3 inverters be used for 3 phase power ?
I want to thank all who have shared thoughts with me, as jraef or p3 pointed to policies at the end of his post, i had not read them prior to his comments.
I do seem to fall into #8 catagorie, as i am not formaly educated in eng. I have taken a few hours at a community college in electrical path.
My background for 45 years is too varied to call any one thing a speciality. I have been self employed for the most part in construction and heavy equipment, there have been other fields of exposure such as, marine,aviation, and high tech semiconductor wafer fabrication(AMD).
I have always been a owner operator, so have never commanded a workforce, which means maintanence/repairs have always been at my own hands. This has resulted in basic understanding of several disiplines without a solid foundation in any one of them.
Of all our heros Tesla is my #1.
In my little understanding of heat pump principles and Tesla's Turbine with a certain modification in its construction, there should be three benifits from the transfer of thermal energy from the atmosphere, they are cold air, condensation, electricity or mechanical work.
With all these things said it should be clear how i plan to keep my batteries charged, and why if not now, later i will be red flagged on this forum.
Should anyone care to continue dialog with me please respond with how and best method. Again thanks for your responses as they have been very helpful.
Ron Light
RE: Can 3 inverters be used for 3 phase power ?
RE: Can 3 inverters be used for 3 phase power ?
Overunity has several forums.
http://www.overunity.com/
Fuelesspower has plans that are guaranteed to work. All the way up to 350hp.
http://www.fuellesspower.com/
Good luck, and don’t let math or physics get in your way.
Barry1961
RE: Can 3 inverters be used for 3 phase power ?
First i do not believe in overunity, but i do believe thermal energy can be extracted from objects or mediums and converted to electrical or mechanical work.
As an example 1 gallon of water has a certain weight, a well known fact. This same gallon of water has a btu value of a certain quanity from 32 degrees to 211 degrees, in which the weight has very little change.
If the water is allowed to drop a given distance for a certain quanity of time there will be a mathmatical value that can be assigned to this action, and if the system can extract and apply the thermal value from 211 down to 32 degrees and add to the value of the weight(kenetic) energy at the same time this would in my mind represent nearly 100% of the total energy available. There will be the normal losses of thermal and friction to known and unknown areas.
If my thinking does not fly in the face of physics then i will try and explain how to accomplish what is in my mind.
One other thing before we get into a very deep subject, is an idea that has been in my mind for some time. An electric motor that is suspended so that both housing and armature can rotate but in opposite directions, each having a flywheel that is of proper size and weight to give equal values of resistance to each unit, if frequency is not an issue then more voltage can be applied and devided between the two counter rotating units thus increasing power by a large factor, if the unit is used as both motor and generator then keeping it cool is a source for heat that is reapplied in the system of thermal conversion. (heat pump cycle)
Hope this has not put everyone to sleep and yet there is so much more.
Ron L
RE: Can 3 inverters be used for 3 phase power ?
But alas, I for one do not want to get into a wild discussion about energy recovery and hypothetical energy-savings through novel schemes.
I once watched in horror as two guys went thru thousands of dollars building and running a perpetual motion machine that had a motor running a hydraulic pump that ran a generator that ran the motor.. Sheesh. Sad to the point of disturbing.
RE: Can 3 inverters be used for 3 phase power ?
I don’t know what it is about flywheels that makes people think they can get more out of them than they put in. I think for every person who believes they can multiple power by pumping water back uphill in a hydroelectric plant there are 10 who believe that attaching a flywheel to a motor or generator will multiple the power.
Ron, I really hope you do not spend a bunch of money on this. There are hundreds of millions of flywheels on machines all over the world. The math for calculating stored energy in spinning flywheel is easy and readily found.
I hope you have fun with your project.
Barry1961
RE: Can 3 inverters be used for 3 phase power ?
My original post should have been within the intent of forum guidelines, novel schemes is where we went, for that please accept my apoligies.
Some may have jumped to conclusions about what was being described and how things were going to be used and what results were being expected.
Itsmoked requested a clear statement, as i started to try and do this it dawned on me that it would only continue the novel schemes thinking. Please indulge this attempt at a clear statement.
Barry1961 mentioned multiplying energy with a flywheel, I agree this cannot be done. As one article in my past studies stated, " pound for pound a flywheel will store 10 times more energy than a lead acid battery" if this is anywhere near accurate it only represents a storage medium.
My intent is to keep all my energy requirements (in and out ) within the top 5% of this flywheel action. As for adding any additional power to my flywheel my aproach will be to utilize the concept of two sealed chambers one inside the other. The only connection to the outside enviornment would be electrical wires sealed at their thru holes.
The outer chamber is a low pressure zone and the inner chamber is a higher pressure zone. The inner chamber houses completly the motor,generator and flywheel system. The flywheel assembly is made on the basic concept of the Tesla Turbine. It is composed of a group of inner disk and bounded on both sides by heavy steel plates with center openings for air flow.
On the outside of the inner chamber and on either side of the turbine are vacuum motor units, pulling a vacumm on the flywheel unit, also on the outside of the inner chamber are 4 (two on each side) vacuum motors applying a positive pressure to the inside of the inner chamber, and at the same time reducing the pressure of the outer chamber. These six motors will be powered by the internal generator. This air flow is of low pressure and large volume. Still it will have a greater velocity then the speed of the flywheel unit.
The rotation of the flywheel unit by the electric motor keeps the rpm's constant, while the air flow is trying to push thru the disk's outer surface and thru to the internal vacuum in the central area, at a faster rate thus suppling additional energy to the motor (which would show as reduced amp flow).
If my understanding of the first law is correct, then all energy can be accounted for in the two chambers, and the electrical leads from the batteries going in.
Now where i place all my hopes is in the belief that with proper insulation around the inner chamber, and the outer chamber being alum. or copper walls to allow for heat in, this becomes a heat pump, with heat being assorbed equal to electrical energy sent out.
all this being said, i do want to add that the comment about highly organized electricity, and disorganized heat did not go unnoticed. If my thinking is flawed i'm sure this will be the eye opener once i figure it out.
The Three things that have led my thoughts are,
#1 steam jet ejectors
#2 vortex tube coolers
#3 Tesla Turbine therory/with flow thru generator
It is my belief, these three things assembled in in proper configuration will be able to give a heat pump system that absorbs heat and gives off electricity in exact and equal quanities.
If open to the atmosphere the three results would be,
#1 cold air
#2 condensation
#3 electricity
Now that i have totaly ruined my image, i'll refer back to my original post about 3 inverters powering a 3 phase motor and say that most likely VFD's will be the best choice. Thanks for the info.
And "barry1961" thanks for your last thoughts, i have kept my cost down by trying not to buy anything that does not have some other use in my business or hobbies, my costs are only a few hunderd at this point. We have a community dumpster nearby and you would not belive some of the good working things that people throw away.
If time is kind to me there should be some test runs in a few months, and if there are any positive things to report i will make a post, if that is ok.
Thanks
Ron Light
RE: Can 3 inverters be used for 3 phase power ?
1. Weigh the battery in your car, 30lb?
2. Disconnect the coil wire to prevent car from starting.
3. Try to start the car
4. Time how long the engine keeps turning, 1 minute?
5. Make a 30lb flywheel.
6. Make a belt tension “clutch” to crank.
7. Try to start car.
8. Time how long the engine keeps turning, 10 minute?
9. Post your results.
I really don’t think you can make a 30lb flywheel that will crank an engine 10 times longer than a battery of the same weight. It is theoretically possible though, but the flywheel would have to be made of unobtainum to prevent it from self destructing.
Before you make a flywheel you should know they will burst if designed wrong or run too fast. And there is no early warning before they do burst.
Save your money. Learn the math. Do the math. Math is your friend.
Barry1961
RE: Can 3 inverters be used for 3 phase power ?
The flywheel system could be designed to last for years with no maintenance, which makes it attractive for some applications.
Cost wise there is no comparison, of course. I'd guess the flywheel would be a minimum of twenty times more expensive than a lead acid.
Incidentally, the round-trip efficiency of a lead acid is pretty much defined by the difference in charge and discharge voltage - about 95% efficiency in practice.
Cheers
Greg Locock
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.
RE: Can 3 inverters be used for 3 phase power ?
RE: Can 3 inverters be used for 3 phase power ?
Cheers
Greg Locock
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.
RE: Can 3 inverters be used for 3 phase power ?
Let me restate myself.
I think yur dreaming if you think you can get 95% out of a lead acid system.
Lead acid batteries have an efficiency no better than 80% and this is the pure power in verse power out. If you include the efficiency of the charger/battery "system" as I referred to above, then you are now talking 60% to 70%.
So I don't know what "practice" you are referring to.
RE: Can 3 inverters be used for 3 phase power ?
Cheers
Greg Locock
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.
RE: Can 3 inverters be used for 3 phase power ?
You can also put energy into air and take energy out of air. I don’t know off hand what the efficiency of the various methods are but I don’t think they are very efficient. I am not aware of any devices that use air to store energy.
Barry1961
RE: Can 3 inverters be used for 3 phase power ?
While going thru the site and finding answers as to how to best use the powerful tools at pretty much anyones disposal, i am almost overwhelmed at all the topics and information that is contained in these pages.
I will be considering a lot of things for a number of days i'm sure.
As for your illustration of battery cranking engine, and flywheel turning engine, i think you failed to consider the pinon and flywheel gearing.
However it did bring one thing out and that is, if you use the battery to drive a motor which has a flywheel on its shaft for a given time to a certain speed, then reverse the process so that the motor is now a generator, how much charge is put toward the battery?
Now you have to consider effeciency losses of all three, motor,generator, and battery and possible others.
This is not a 5 min. exercise.
I still have lots of thinking to do.
Thanks
Ron L
RE: Can 3 inverters be used for 3 phase power ?
Vortex tubes for instance look like really interesting devices that appear to separate thermal energy from moving air, but the fact that is constantly left out of discussions about them is how much energy went into getting the air moving in the first place, and it is tremendous! I once worked on a system to keep a man cool in a foundry area using compressed air into a vortex cooler since the compressed air was already available and electricity was not. Base on the worker producing 2400BTU/hr (heavy work), which equates to about 700 watts, the vortex cooler needed 100cfm at 40 psi. What I discovered is that it took 7-1/2HP of air compressor to get that! So that is 5600W input to extract 700W, a loss ratio of 8:1! Can you design a vortex tube to extract energy from low velocity air movement? I suppose, but it would need to be HUGE!
Ron14, here is what I think you are trying to describe:
You want to put energy into a system in a closed environment to start a generator in one chamber, use the generator to run compressor motors that create a pressure differential between the two chambers, and use air flow between them to keep the generator running after the external power input is removed. In addition, you think you can trap the losses in the generator and compressor motors as heat in that chamber, use the heat to expand air in that chamber, adding to the airflow across the generator. I'm not sure where the vortex tube came into your scheme, but it doesn’t really matter to what I think the issue is. IF you had absolutely perfect, and I do mean PERFECT sealing and thermal insulation, at the very best, the system could theoretically sustain itself. The big BUT in this is that absolute insulation and absolute sealing does not, and arguably cannot exist. So in that scenario any even miniscule amount of energy loss would be essentially sap it of it's own sustenance energy, which would (IMHO) have a logarithmic effect on energy reduction, thus dooming it to rapid failure.
And the bigger question is, WHY? It really is not going to create energy, and you cannot extract any useful energy from it without causing it to rapidly decline, so I doubt that it's storage capability will be any better than any existing system, maybe even worse. On top of it all, it will cost an awful lot to make.
"Our virtues and our failings are inseparable, like force and matter. When they separate, man is no more." Nikola Tesla
Member, P3
itsmoked (Electrical)
Well put jraef. A star.
Ron14 (Mechanical)
(OP)
well...
stevenal (Electrical)
Except for the resistive losses, heat pumps do not convert electrical energy into heat. They simply move heat around. The COF deals with electrical energy in and heat out ignoring the heat input to the system. By this measure, a gasolene pump is outrageously efficient. A few watt hours of electric power in and lots more BTUs worth of gasolene comes out. And they want $3 per gallon?
stevenal (Electrical)
Forgot to spell check. Make that "gasoline."
Barry1961 (Industrial)
The starter is only engaged with the ring gear during the act of starting. The starter is only connected to the battery during starting. The starter stator is open unless starting.
Ron14 (Mechanical)
(OP)
Thanks stevenal
stevenal (Electrical)
I thought my analogy was clear enough. In my gas pump example I ignored the other energy input into the system, the gasoline in the below ground tank. Like the heat pump, the gasoline pump simply moved the energy from one location (below ground tank) to another (vehicle fuel tank). The ratio of fuel energy out to electric energy in is nearly meaningless, and certainly does not qualify as efficiency. Efficiency is the ratio of the total output energy to total input. Neither pump will work the entropy backwards.
itsmoked (Electrical)
Ron14; Do not confuse "heat availability" with useful energy. Moving a bunch of heat from one side of a wall to another with a COP is a case where a bunch (a whole bunch) of electricity [high entropy] {high quality} is used to shuffle even more [low entropy]{low quality} energy from one side of a wall over to the other side of a wall. The only real gain in the energy being shifted is the {real] gain supplied by the higher quality waste heat being rejected by the compressor. (From the electricy being supplied to the compressor).
Ron14 (Mechanical)
(OP)
Alright guys....
aolalde (Electrical)
Returning to the original post and based on all these long extraterrestrial discussion, I do not see how TOM14 could understand and synchronize a three phase system out of three independent drivers.
jraef (Electrical)
LOL aolalde, we got so far off onto the energy/entropy issue that we lost trrack of the original question! Good point.
Read the Eng-Tips Site Policies at FAQ731-376
RE: Can 3 inverters be used for 3 phase power ?
It is kind of like making a solar panel. Takes a huge amount of thermal energy. Thousand degrees. The metal frame had to be made. It came from explosives, diesel, rubber consumption brought from other countries, etc, etc.
Then it needs to run with full output for 20,000hrs just to break even on the energy that went into making it! Same as a car. People run out and buy a new "more efficient" car discarding a working car whose "inherent" energy is more than all the fuel that will ever be saved with the new one!
The big picture for your project, [besides the, fact that it cannot work], is the same as my above statements. The cost and energy that you might ever derive is offset by the cost and energy and complexity of the device's construction.
RE: Can 3 inverters be used for 3 phase power ?
This thread has gone longer than i expected from a simple question, but i feel i'm near to an understanding that has been a long time comming.
It's like i'm continually walking into a wall when i know the door is only 2 feet to the left.
It will take a few days to put my words in order (hopefully). For now i'll state what i believe my biggest hangup is, which i felt "itsmoked" was close to seeing when he mentioned working entropy backwards.
I can't seem to understand the difference in a heat pump COP and 100% effeciency.
I have a McGraw-Hill encylopedia of energy, that gives the illustration of a heat pump with a COP of 17.7, and uses the terms " 1(Kwhr) of electric energy to compressor" delivering 3413x17.7=60,000 BTU/hr of refigeration or heating effect as required.
Now to me the value of 1 BTU from electric coil into steam and 1 BTU being absorbed from atmosphere or water into a reduced steam temp of say 40 Degrees is not a bit different.
Now describing the system that produces these effects is what will take some time. But if i can see the light i might not have to describe what i have in my head.
Does this make sense?
Ron L
RE: Can 3 inverters be used for 3 phase power ?
RE: Can 3 inverters be used for 3 phase power ?
RE: Can 3 inverters be used for 3 phase power ?
You can gear the flywheel any way you want and it will not spin the engine for any length of time approaching what the battery will do thru the starter. For the flywheel to store energy approaching the battery it would have to have an OD so large that the spokes and hub would be paper thin, or less, and be spinning at a very high speed. This of course would cause the flywheel to burst.
Every time you change the state of energy you use some energy to make the change.
Barry1961
RE: Can 3 inverters be used for 3 phase power ?
I do not understand your gas pump example, but i do understand that the energy to the refigerant compressor is used to move a volume of gas that when allowed to expand has the ability to absord 60,000 BTU, but rather than let this heat just warm a room, why not apply -the 300+? (just a guess) degree gas inside a coil, to a cool water supply that is about to be injected into a steam generator.
I thank i just confused myself again.
Anyway what i thank is close at hand for my understanding is, if each cycle represents 60,000 BTU - 3413BTU how much of the 56,587 BTU could be used to add back into heat that does not need to be generated by a power process?
Now what "itsmoked" stated was, (if i understand right) that the 3413 BTU is (highly organized electricity)
And that the 56,587 BTU is (disorganized heat). When this becomes clear in my mind, the dissapointment will come rushing in, untill then i see this as a large quanity of heat to be used in some way, prior to my electrical generation of steam.
I sure hope this discussion is helping someone else in the world to better understand what i seem to be having so much trouble seeing, and that it is not too much a waste of forum time.
Again THANKS for everyone's generous offer of time and thoughts.
Ron L
RE: Can 3 inverters be used for 3 phase power ?
RE: Can 3 inverters be used for 3 phase power ?
RE: Can 3 inverters be used for 3 phase power ?
I think i just moved two feet to the left, now if i can just move forward a few steps i'll be thru the door.
I have a job to do ( actually make some money) i'll be back in a few days to try and catch up.
The last two post have helped and i thank i see some light.
Thanks again
Ron L
RE: Can 3 inverters be used for 3 phase power ?
RE: Can 3 inverters be used for 3 phase power ?
"Our virtues and our failings are inseparable, like force and matter. When they separate, man is no more." Nikola Tesla
Member, P3
itsmoked (Electrical)
Yeah, but I already said just that aolaode in the first response anyway!
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RE: Can 3 inverters be used for 3 phase power ?
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