The Main Difference Between a PLC and Relay Control System

question 42

Multiple Choice

The main difference between a PLC and relay control system is that:

• A)different types of input devices are used.
• B)different types of output devices are used.
• C)different input and output voltage levels are used.
• D)one uses hardwired relay control logic and the other uses programmed instructions.

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Definitions:

Thymus Gland

An organ located in the chest, which plays a vital role in the development and maturation of T-cells, essential for the immune response.

Reticular Fibers

Fine, branching fibers forming networks in various tissues and supporting cells in organs like the spleen and lymph nodes.

Medulla

The innermost part of an organ or structure, often referring to the medulla oblongata in the brain, which controls vital functions such as breathing and heart rate.

Lymphocytes

White blood cells that play a crucial role in the immune system, responsible for producing antibodies and other substances to fight infections.