GE GFK-0804B manual On Timer

4

On Timer

The On Timer turns ON an output after a specified time period. The time period can be from 0 to 6553.5 seconds. However, if a constant is used for the Preset value, the time period can be from 0 to 3276.7 seconds. To program a timer function, enter two inputs (in the example below, I1, and I2), and two parameters (R1 and 100 in the example).

The first input controls operation of the timer. Timing only occurs while I1 is 1. The second input to the timer clears the current timer value to 0.

The first timer parameter is a register memory location for PLC to store the current timer value.

The second timer parameter is the timer length, in intervals of 0.1 second. If this number should always be the same, you can enter it directly, as shown in the example. Or, if you want to be able to change the timer length using the Hand-held Programmer, instead enter a register from R385 to R500 as the second parameter for the timer. The current timer value (in R1 below) will not increment beyond its programmed length (time period), even if I1 remains closed and I2 remains open.

Programming Software Instructions

If you are using the programming software, refer to the instructions on page 4-16.

Example and HHP Instructions

Ladder Diagram

I1C1

R1

ONTMR

I2

100

46026

Hand-held Programmer
START		I1
START		I2
TIMER	F1	R1
		100
OUT		C1

Timing Diagram

Input I1

Input I2

When I1 is 1, the timer is enabled. The timer setting is:

100 x 0.1 = 10 Sec.

Register R1

Coil C1

100

0

During the operation of the timer, if I1 switches to 0, the timer is on hold. When I1 is 1 again, the timer resumes timing.

When the timer reaches the set value (10 seconds), output coil C1 activates.

Input I2 is used to reset the timer. When both I1 and I2 are on, the timer remains reset.

GFK-0804B Chapter 4 The Micro PLC Instruction Set 4-17