Chapter 7, Problem 9P

Program Plan Intro

Timer:

• Timer is mainly used to keep an output ON for a specific length of time.
• It provides a preset delay to the control actions.
• In a timer, the output will be energized when the preset value becomes equal to the accumulated value.
• Three different types of timers include a Delay-OFF, a Delay-ON, and a Delay-ON-Retentive timer.

Timer ON Delay (TON):

• TON refers to an on-delay timer.
• The on-delay timer is the most commonly used timer.
• TON counts the time-based intervals as soon as the instruction becomes true.
• Here, the output changes its state from low to high when the timer provides some time delay (instruction goes from OFF to ON state).

Explanation of Solution

b.

Given:

Consider the given conditions,

• Input = True
• EN = 1
• TT = 1
• DN = 1

Explanation:

The given program uses TON, so if the input is true, then the instruction will start to execute the program.

• The timer “T4:0” will start timing and the EN signal bits get activated.
• Next, the TT also turns into “true” until the accumulated values attains the preset value “10”...

Explanation of Solution

c.

Given:

Consider the given conditions,

• Input = False
• EN = 0
• TT = 0
• DN = 0

Explanation:

• The given program uses TON, so if the input is true, then the instruction will start to execute the program...

Explanation of Solution

d.

Given:

Consider the given conditions,

• Input = True
• EN = 1
• TT = 0
• DN = 1

Explanation:

The given program uses TON, so if the input is true, then the instruction will start to execute the program.

• The timer “T4:0” will start timing and the EN signal bits get activated...