Chapter 16 Review Questions Timing and Counting functions

Dashpot

Which type of timer can provide a time delay between activation and contact actuation, but its time setting

cannot be precisely set and cannot be set for long periods of time?

Solid state programmable

Which type of timer includes multiple separate timers that can be set individually for different times?

Digital devices used discrete signals that only have two states.

What is meant by a digital input controlling a timer?

Analog inputs use continuous signals

What is meant by an analog input controlling a timer?

Off delay

What type of timer is used to control the fan motor in a furnace so that the fan continues to operate for a time

after the heating source is turned off in order to distribute the remaining heat from the furnace?

On delay

What type of timer is used to control the light in a garage door opener so that the light turns on when the

opener is activated and remains on for a set period of time after the opener button is released?

A timer that operates with equal on and off time periods.

What is a symmetrical recycle timer?

Allows for both on and off periods to be set independently

What is an asymmetrical recycle timer?

The load is energized

When adding a timing code to a load controlled by a timer, what does an "X" indicate?

The load is de energized

When adding a timing code to a load controlled by a timer, what does an "O" indicate?

Yes

When adding an XOX timing code to a load, is the load ON during the timing period?

The switch can control the contacts, which will turn the timer on and off

When connecting the input switch that controls a timer, what is the advantage of using a contact-controlled

timer instead of a supply voltage-controlled timer?

Voltage divider network, two comparators, flip flop, two control transistors, and a power output amplifier.

In a 555 timing circuit that uses an external RC time-delay circuit, what components are used to determine

the amount of time delay?

Flip flop

What is the name for an electronic switch that has two outputs in which one is high anytime the other is

low?

102 seconds

If a programmable timer is programed for a time setting of 1020 and the time base is programmed for 0.1 sec,

how long is the timer programmed for?

1,020 seconds

If a programmable timer is programed for a time setting of 1020 and the time base is programmed for 1 sec,

how long is the timer programmed for?

16:30 to 18:00

When programming a real-time clock to operate its contacts from 4:30 PM to 6:00 PM, what is the time

setting in military time?

Retentive timer

What type of timer still retains its accumulated time value after a power loss?

A totalizator count the total number of events and counter counts all the inputs and provides and output.

If a totalizer and counter both keep track of the number of counts, what is difference between the two?

Removing power to the counter resets it, but a third input can also be used as the reset input.

If the timer of an up counter uses an input switch (such as a limit or photoelectric switch, etc.) to add counts,

how are the counter's accumulated counts reset back to zero?

2

What is the minimum number of individual inputs required to operate an up/down counter?