Phasing nightmare

[snowhead]

Any motor / transformer etc gets hot, that's energy loss.

So if he put the transformer and motor in an insulated box they wouldn't loose heat :6:

 

[Besoeker]

So if he put the transformer and motor in an insulated box they wouldn't loose heat :6:

Yes they would. But if the heat can't be dissipated to the outside world, their temperature will just continue to rise untill they cook their bollicks off and fail.

 

[PEG]

...Is that it then? Nothing to fear trip trip tropping over THIS bridge then...:willy_nilly:

 

[davesparks]

do the research....... i know for a FACT that a 12VDC starter CAN run a 48V alternator :/ all you need is the torque to turn the alternator..... which the starter can do as it can start 6L V8 diesel engines with ease


if you think im wrong then show a detailed calculation of how you came to the conclusion the 12VDC motor WONT be powerful enough to turn a 48V alternator at its required revolutions

A 12V DC motor could easily power a 48V alternator, or even a 240V alternator, if you select a powerful enough motor.
What it cannot do is sustain its operation using only the electricity developed in the alternator, the motor will eventually stop turning unless energy is introduced in to the system from an outside source.

Try the first law of thermodynamics and the law of conservation of energy for your proof of this.

Within a closed system energy cannot be created or destroyed, it can only be converted from one form to another.

So consider a 12V motor driving a 12V alternator which in turn charges a battery which then powers the motor. And assuming the battery is fully charged to start with.
Let's also assume that the battery holds 100 units of energy.

Chemical energy in the battery is converted into electrical energy and a little bit of heat, say 99units of electrical energy and 1 unit of heat energy which is lost.

The electrical energy is transferred through wires to the motor, the motor then converts it into mechanical energy, say 97 units of mechanical energy, 1 unit of heat energy lost from as heat energy as the electricity flows through the wires and 1 unit lost as heat energy through friction in the motor.

The mechanical energy is transferred through a drivebelt to the alternator, friction on the two pulley wheels converts another 1 unit of energy to heat, our total is now 96 units.
The alternator converts the mechanical energy to electrical energy, and again heat losses from friction are 1 unit, with heat losses from the flow of electricity being 1 unit. Total is now 94 units of energy.
The AC electricity from the alternator then has to pass through a rectifier circuit to convert it to DC and then a charging circuit for the battery, these generate a lot of heat too so allow another 2 units of energy loss there.
So now we have 92 units arriving at the battery to recharge it, which is again the conversion of electrical energy to chemical energy, and again there will be losses, let's assume 1 unit is lost here.

The total energy which gets stored in the battery is then 91 units with 9 of the original units having been lost as heat. The system is 91% efficient.

As there is now less energy to turn the motor it will not turn as fast and as a result the losses in the system will increase.

It won't take long for the total amount of energy left in the system is not enough to turn the motor, and so it stops!

 

[PEG]

...Or as an old science lecturer once said ..."boys,friction makes heat,yes?"..."Heat boils water,yes?"..."...so exactly how long would it take for donkey to ---- a bucket of water before we can all have a cup of tea?"...physics has an answer for everything :bow:

 

[Silly Sausage]

...Or as an old science lecturer once said ..."boys,friction makes heat,yes?"..."Heat boils water,yes?"..."...so exactly how long would it take for donkey to ---- a bucket of water before we can all have a cup of tea?"...physics has an answer for everything :bow:

I know, knee burns...OUCH!

 

[gnuuser]

For free power, get a ginormous cage wheel and fill it with hamsters.
The trick is getting them all to run in the same direction.

thats easy put a cage of cats on one side and they will all run away from the cats

 

[Eryrwyn]

http://youtu.be/Fv53K9MnDuM

http://youtu.be/Fv53K9MnDuM

Were you inspired by this video Michael ?....

 

[Dan]

Just bumping some threads in the Electrical Wiring Theories and Regulations forum category here on our Electricians Forums. If this specific topic isn't current, just ignore it, it'll drop off the list in no time. However, if it's something you'd like to contribute to, feel free to reply and bring it back into current discussion.