Conrad Course material 10025 14 years and over 10025 Manual De Usuario

indicator. The shining of the LEDs can hardly be seen in bright ambient light. In a room it is also 
possible to shield the LEDs with a piece of cardboard. 
 
Fig. 37: (omitted) 
 
Fig. 38: Shading with a) film and b) cardboard 
 
Now slowly shade part of the module with your hand. The speed of the motor becomes slower, or the 
motor totally ceases to turn.  
 
Fig. 39: The motor or alternatively the LEDs with the 100 Ω series resistor can be connected to the 
solar module. 
 
Now you can do further experiments of this kind: 
Produce a slight shadow by means of an additional glass disc or a matt film that is held between the 
light source and the solar module. 
Produce a heavy shadow by means of a piece of cardboard that you hold directly over the solar 
module. 
Shade individual solar cells of the solar module by placing a piece of cardboard directly on one or 
several solar cell(s) of the solar module. 
 
Fig. 40: Individual solar cells shaded 
 

In the case of large PV systems that are equipped with crystalline solar modules, the topic of shading 
is an important one. So that the entire solar generator does not fail in case of partial shading, e.g., 
due to a leaf, Schottky diodes are used as “current bypass” around the shaded solar cell. With 
defective diodes, a hot spot can develop in an extreme case, with individual solar cells being 
destroyed. 

 

12.  Step: Orientation of the module toward the light source 

Experimental set-up: solar module, patch panel, motor 
 

For the following experiments, you need a bright light source (or full, direct sunlight) for the solar 
module. 

 
Fig. 41: Experiment with orientation of the module toward the light source 
 
Fig. 42: Circuit diagram with two main orientations 
 
Take the solar module between thumb and index finger (without shading the surface) and orient the 
surface of the module as much as possible at a right angle to the light source. How fast does the 
motor axle turn? Now vary the orientation toward the light source by moving the solar module back 
and forth and observe the motor. 
 

The more perpendicularly the light beams strike the solar module, the more light energy the solar cells 
can transform into electric current and thus supply the motor. 

 
Fig. 43: Schematic diagram of the inclination angle toward the light source. The number of arrows 
striking the solar module stands for the light intensity. 
 
Orient the solar module precisely toward the sun or another light source by placing cardboard, blocks 
of wood, etc., underneath the solar module. Observe the motor. As described further above, the motor 
axle turns. Now you have earned a break. Wait about an hour (or several hours) and then look at your 
experimental set-up again. The sun is no longer precisely perpendicular to the solar module; the motor 
turns more slowly or has even stopped. Since the light source, i.e., the sun in the sky, moves from 
east to west (of course only seemingly), optimally the solar module ought to be guided in its orientation 
toward the sun.