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It can be found in cars, washing machines, medical equipment, aircraft,
etc. We can see that relays are being used in control systems and power systems
industries to protect the system or load circuit from unexpected damage.
Read the article again and complete it with verb phrases (A-H)
A. detects the fault
B. will push the contacts away
C.
generates the magnetic field
D.
is applied to the coil winding
E.
have an electromagnet, movable armature, contacts and spring
F.
must be controlled by one signal
Write a summary of the text
Give a talk about protection devices. Make use of the terms and topic
related words. You can use the following questions
•
What is the function of circuit breakers, fuses, switches and relays?
•
What do circuit breakers, fuses, switches and relays consist of?
•
How do circuit breakers, fuses, switches and relays work?
•
What is the difference between a circuit breaker and a fuse when they have
to resume normal operation?
•
What are the requirements of a circuit breaker?
•
What are the types of simple switches and how to tell them apart?
•
How many circuit paths do simple switches usually control?
•
What is the difference between safety switches and ordinary simple
switches?
•
What do safety switches monitor?
•
What happens if any irregularity is detected within the circuit?
•
What are the advantages of fuses over circuit breaker?
•
What is rated interrupting capacity?
•
What are circuit breakers, fuses, switches and relays used for?
Choose one of protective devices and study how protection devices
have improved since the first was invented. Prepare an infographic. Share
your results with your groupmates
