ETS-1843 17.) Basic Timer Control On-Delay Off-Delay

The contact shown in the figure is a(n) __________. (has arrow at bottom) a.) N.C off-delay relay contact b.) N.O off-delay relay contact c.) N.O on-delay relay contact d.) N.C on-delay relay contact

a.) N.C off-delay relay contact

One common method of unloading a compressor motor during startup is to use a control circuit with a timer relay. a.) True b.) False

a.) True

An off-delay timer's contacts change to their energized state after the delay. a.) True b.) False

b.) False

The contact shown in the figure is a(n) ___________. (has upside down y at bottom) a.) N.O on-delay relay contact b.) N.C on-delay relay contact c.) N.O off-delay relay contact d.) N.C off-delay relay contact

b.) N.C on-delay relay contact

Which of the following is not a common timing mechanism used on timer relays? a.) Solid-state timers b.) Pneumatic timers c.) Hydraulic timers d.) Motor-driven timers

c.) Hydraulic timers

Which of the following might cause the N.O contact of a timer relay to be closed whether the coil is energized or not? a.) Mechanical problem with the timer relay b.) Contact is stuck closed c.) Contact is shorted d.) All of the above e.) None of the above

d.) All of the above

Using timers to sequence the operation of a machine is called _________. a.) Event-driven sequencing b.) Time-driven sequencing c.) Delay sequencing d.) All of the above e.) None of the above

e.) None of the above