Welcome to Module 18, which is about Terminal Blocks, Relays and Timers.

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Welcome

Welcome to Module 18, which is about Terminal Blocks, Relays and Timers.

TERMINAL BLOCKS are modular, insulated blocks that secure two or more wires together and consist of an insulating body and a clamping device. Their flexibility allows wiring to be centralized and makes it easier to maintain complex control circuits.	Figure 1. Terminal Block
RELAYS are switches that open and close circuits electromechanically or electronically.	Figure 2. Relay
TIMERS control timing in applications where functions need to be delayed, or loads need to be maintained for a predetermined period of time.	Figure 3.

Like the other modules in this series, this one presents small, manageable sections of new material followed by a series of questions about that material. Study the material carefully, then answer the questions without referring back to what you’ve just read. You are the best judge of how well you grasp the material. Review the material as often as you think necessary. The most important thing is to establish a solid foundation to build on as you move from topic to topic and module to module.

A Note on Font Styles

Key points are in bold.

Glossary items are italicized and underlined the first time they appear.