DESCRIPTION

Technical Description

Photovoltaic solar modules convert sunlight directly into electrical current and are therefore an ideal component for renewable energy supply. Typical solar modules from the field of photovoltaics are made of several silicon solar cells connected in series.

The ET 250 trainer contains two such solar modules. The tilt of the modules can be adjusted. Cables can be used to connect the two modules in series or in parallel. A slide resistor simulates varying loads. Thus the slide resistor makes it possible to record current-voltage curves.

The separate measuring unit provides displays for all relevant variables. Two power resistors in the measuring unit are used to expand the measuring range for measurements at low illuminance. Sensors on the solar module detect illuminance and temperature.

In order to ensure there is sufficient illuminance, the trainer should be operated with sunlight or the optionally available HL 313.01 Artificial Light Source. 

The well-structured instructional material sets out the basic principles and provides a step-by-step guide through the experiments. 

The trainer ET 250 can be expanded by using ET 255 Using Photovoltaics: Grid connected or Stand-alone.

Learning Objectives / Experiments

- physical behaviour of solar modules under a variety of effects
  * illuminance
  * temperature
  * shading
- familiarisation with key parameters
  * short-circuit current
  * open-circuit voltage
  * current at maximum output
  * voltage at maximum output
- relationship between module tilt, illuminance,short-circuit current and electrical output
- recording a module's current-voltage curve
- determining the efficiency
- connection types for the modules
  * series connection
  * parallel connection
- how cells covered by shadow affect the current-voltage curves