Hex Lock and the Hub Quick Connect
The hex-shaped driveshaft allows you to connect the hex lock to the driveshaft. If you mount your gears or a weightlifting spool on the back of the nacelle, the hex lock will not slip on the driveshaft.
The Hub Quick Connect (HQC) allows for easy removal and attachment of the hub. This enables users in busy classroom environments to change blade configurations quickly and easily.
Strong wind, large or out of balance turbine blades, and wear can make the HQC unstable.
The HQC ships with a small screw holding the hub in place. If the hub is still slipping, adjust your blades to make sure their weight, pitch, size, and shape are all equal so that your rotor is well balanced. Push the hub in as far as you can. Glue the hub into the HQC.
Note: The hub is designed to have a very tight fit to the Quick Connect, but if your blades are unbalanced or your turbine is not directly facing the wind, it may come loose. Be careful with blades that are out of balance.
Lifting weights with the wind turbine is another great way to explore wind energy and provide students with a simple visual display of mechanical work. To convert the kit to a weightlifting turbine, watch the assembly video at www.vernier.com/x384
Compare the mechanical and electrical power of wind by setting up a weightlifter.
To generate the electricity, the generator has to spin very fast. To summarize the process, the faster the coils rotate near the magnet, the more electrons will be pushed along the wire. If you’ve seen a utility-scale wind turbine, you probably noticed that the blades spin pretty slowly. To get the generators to spin fast enough, they use gears. Gears give a wind turbine mechanical advantage and multiply the mechanical force of the turning blades. This is done by using gears with different numbers of teeth. When the larger gear makes one full revolution, the smaller gear has to spin faster to keep up.
This kit offers three different gear ratios. The smallest gear attaches to the generator driveshaft and is called the pinion. The pinion gear has 8 teeth. The other three gears attach to the main hex shaft and have 16, 32, or 64 teeth.
A “gear ratio” is the relationship between the number of teeth on two or more gears that are meshed. So when you ride your bicycle, the gear in front might have 48 teeth, while the gear in back has 16 teeth. That would mean every time your pedals spin around once, the back wheel spins three revolutions (48÷16 = 3). This is called a 3 to 1 (3:1) gear ratio. Wind turbines work the same way except that they have much larger gear ratios. A modern wind turbine may have a gear ratio of 100:1 or more. So every time the blades make one revolution, the generator shaft spins 100 times.
Using the 64-Tooth Gear (Largest Ratio)
If you are using the largest gear size, you will notice that it will only fit with hex nuts under the motor mounts, as wingnuts are too tall. If you are using the smallest gear size, you will have to use hex nuts above the motor mounts. Give the hub a spin to make sure that the gear turns and rotates the small pinion gear on the motor.
Note: Using the 16 tooth gear requires the High Torque Generator which is sold separately as order code KW-HIGEN.
Using the 16-Tooth Gear (Smallest Ratio)
Since the 16-tooth gear is so small, it is challenging to mount the generator high enough in the main body to mesh gears. In order to use this small ratio, you have to use the High Torque Generator. Remove the upper half of the Motor Mount and slide a small cardboard or folded paper shim in between the generator and the main body housing. You will have to adjust the width of this shim to get the gears to mesh perfectly.
Tighten the nuts below the Motor Mount to secure the generator in place. If the gears do not mesh well, adjust the shim.
To determine the proper polarity of the turbine, connect it to a voltage probe or a multimeter. If the voltage reading is positive, the lead connected to the red voltage probe or multimeter wire comes from the positive terminal. If the voltage reading is negative, the lead connected to the red voltage probe or multimeter wire comes from the negative terminal. It is a good idea to mark the wires with tape so you know which is positive and which is negative.
The DC generator in the wind turbine is a DC motor that spins using the energy in the wind. The magnets and wires in the generator transform the energy in the wind into electricity. By manipulating the strength of the magnets used and coils of wire inside the generator, we can affect the power output.
With the optional GENPack kit (order code, KW-GP), you can construct your own generator instead of using one of the stock generators. Explore Faraday’s law, AC power generation, and electromagnetism to learn about how electricity is generated.
The GENPack fits into the nacelle. It includes a powerful neodymium magnet, copper magnet wire, and a housing to build your generator.
A well-constructed GENPack generator can vastly out-perform the stock generators included in your kit!
Adding the GENPack expands the experimental value of this kit