Quiz 4 Chapters 7 & 8 PLC

The timed relay contact shown is designed to operate so that:

• a. when the relay coil is energized, there is a time delay in closing

• b. when the relay coil is energized, there is a time delay in opening

• c. when the relay coil is de-energized, there is a time delay in closing

• d. when the relay coil is de-energized, there is a time delay in opening

The timing diagram shown is that of an

• a. on-delay timer circuit (NOTC contact)

• b. on-delay timer circuit (NCTO contact)

• c. off-delay timer circuit (NCTC contact)

• d. off-delay timer circuit (NOTO contact)

In the circuit shown, the light will stay off

• a. as long as S1 is closed

• b. for 10 seconds after coil TD is energized

• c. for 10 seconds after coil TD is de-energized

• d. both a and c

In general, the three different types of PLC timers are:

• a. TON, TOF, and PRE

• b. TON, TOF, and RTO

• c. TON, ACC, and RTO

• d. TT, EN, and DN

The amount of time for which a timer is programmed is called the

• a. preset

• b. set point

• c. Done Time (DN)

• d. accumulated time

Normally, when power to your PLC system is lost, when power is restored the counter accumulated value will be:

• a. zero

• b. whatever it was preset for

• c. maximum

• d. unchanged

The down-counter output instruction will increment by 1 each time the counted event occurs. (True/False)

• True

• False

Normally the down-counter is used in conjunction with the up counter. (True/False)

• True

• False

The maximum speed of transitions you can count is determined by:

• a. the amount of PLC memory

• b. the preset value of the counter

• c. your program's scan time

• d. all of these

For the program shown, if the in-feed switch is pulsed 9 times followed immediately by 5 out-feed switch pulses, the accumulated count would be:

• (a)0

• (b) 14

• (c) 50

• (d) 4