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Re: Prototype Oil Drum wind turbine

Wed, 01/04/2017 - 13:55
ULR:
I wonder , at what size S rotor it becomes a better idea to use Carbon Fibre rather than building them using plywood or CDX board?
As hardy as Carbon Fibre is becoming (taylor035 used it for the challenge) I'm thinking it's gotta be getting price ...

Re: Critique this controller

Wed, 01/04/2017 - 10:14
I grabbed this image somewhere.  Hey the board says MPPT, but there are no capacitors and inductors to store energy or transform it.  It is actually built pretty well, just not MPPT.  This footprint is typical of many cheap converters on ebay. 

Re: Critique this controller

Wed, 01/04/2017 - 09:09
While I realise this thread is 2 years old I comment for the sake of anybody reading it now.
This is NOT am MPPT controller. I bought one knowing full well it probably wasn't so I could prove it to myself. If you for example connect a 24 volt 5 amp pa...

report KD 624 about a 46-pole PM-generator for the VIRYA-6.5 available

Wed, 01/04/2017 - 07:23
The title of this new public report KD 624 is: Ideas about a direct drive 46-pole PM-generator for the VIRYA-6.5 windmill meant for driving the 2.2 kW asynchronous motor of a centrifugal pump. The report can be copied from my website: www.kdwindturbine...

Sailboat RE ideas and storage, and mppt...

Tue, 01/03/2017 - 21:52
Hello all! Its been a while since i posted.  I sold my house and bought a sailboat and live on it.  Its a hunter legend 35.5 if ya want to google it.  The ranch is still good and the fanuc servo turbine still puts out over 1kw in good wind.  Anyways......

Re: EMP...Faraday cage on solar panels?

Tue, 01/03/2017 - 20:49
You can buy neutron detectors that will give you a few microseconds early warning. Said early warning can let you use garden variety mosfets to short out the wires going into your "black box"  They are a few hundred dollars and export controlled last I...

Re: EMP...Faraday cage on solar panels?

Tue, 01/03/2017 - 18:26
Key to emp protection is EVERY wire entering the cage has to come in through a surge protector capable of very high speed clamping to ground to protect the contents, 5 nanoseconds or less clamp time. And that protection comes with a STEEP price tag! ht...

Re: Can we discuss electric motor modding here

Tue, 01/03/2017 - 17:50
It makes no sense to me to describe an induction motor stator as "pulling on the rotor" because the rotor is a net consumer of energy.


If I hold a magnet next to a plate of aluminum, I have to push on the magnet to drag the aluminum around. induction ...

Re: Can we discuss electric motor modding here

Tue, 01/03/2017 - 16:58

 OK. I understand what is happening, now. Thank you.

Re: Prototype Oil Drum wind turbine

Tue, 01/03/2017 - 16:20
Quote from: Adriaan Kragten on December 11, 2016, 01:19:13 AM... If a high maximum Cp was measured, it always appears that the scale model was rather large with respect to the dimensions of the wind tunnel. This creates tunnel...

Re: Can we discuss electric motor modding here

Tue, 01/03/2017 - 15:51
Most common types of induction motors work on the repulsion principle.
Its much easier to induce very high eddy currents into a squirrel cage type of solid rotor and these eddy currents in turn produce their own repelling field which is where the torqu...

Re: battery sizing

Tue, 01/03/2017 - 15:46
I'm guessing it's a Group 24.
Druacell is a good name
Bruce S

Re: EMP...Faraday cage on solar panels?

Tue, 01/03/2017 - 14:32
Quote from: joestue on August 10, 2016, 08:22:59 PMQuote from: Ungrounded Lightning Rod
For the grid the solution is to put a resistor in the grounding of the center of the Y on at least one end.  But for the grid such a ...

Re: battery sizing

Tue, 01/03/2017 - 12:21
Would probably be useful to post here a part number if you have one.

Rgds

Damon

Re: PWM a TRIAC

Tue, 01/03/2017 - 12:20
I found that some of my devices/appliances were very tolerant of half-cycle dropping, and some so intolerant that I suspect they may not even meet EU standards for resistance to flicker problems.

In my case I was trying to avoid any obvious bias (for e...

Re: PWM a TRIAC

Tue, 01/03/2017 - 12:03
I repeated my tests again using using a SSR. This is a triac with a zero crossing MOC3041 opto
isolator. These are cheap and it is easy to make your own SSR with triacs or dual back to back SCR
for even higher power. Check the data sheet for schematic...

PWM a TRIAC

Tue, 01/03/2017 - 11:58
Skipping pulses to save energy is a similar to an idea that NASA had about 40 years ago and
licensed the patent to something called the Green Machine. This was phase triggered and
designed to be used on refrigerators, fans and anything that had a mot...

Re: Re wiring/ configuring Panel Voltage.

Tue, 01/03/2017 - 11:51
If you want to attempt surgery on a larger grid tie panel to get 12 nominal voltage out of it you need to start with a 72 cell panel, something in the 300+ watt range. You need to split the buss tabbing between the 36th and 37th cell. Then parallel the...

Got a 12v

Tue, 01/03/2017 - 11:42
Ok I finally got a 12v battery. Can anyone tell me if this would work? If not I am going to take it back.

Duracell Marine and RV 24DC
MCA @ 32 degrees F - 685
CCA @ 0 degrees F - 550
Average mins @ 23 amp draw - 140

Re: Can we discuss electric motor modding here

Tue, 01/03/2017 - 09:28

 joestue, just for my understanding, I found out the GM alternator motor uses a technology that PULLS the rotor around vs PUSHES the rotor around.  Would this help any in the power output of PM vs induction.

 I understand what you wrote before. I am j...