TOFF and TAOFF provide the capability to delay the effect of an input changing from ON to OFF for a specified amount of time. When input turns ON, the output turns ON immediately, but when the input turns OFF, the output is kept ON for the set amount of time, and then turned OFF.
TOFF increases in increments of 0.01 seconds and TAOFF increases in increments 0.1 seconds.
|Type of Timer||Time units||Maximum Time|
|TOFF||0.01 sec||655.35 sec|
|TAOFF||0.1 sec||6553.5 sec|
For TON and TAON there are 2 parameters. The first parameter can be any value from T0 through T99, and the second parameter can be any numeric constant or data register, such as D0.
In the ladder above, when START turns ON, the timer T0 immediately turns ON. When START turns OFF, the timer will start decreasing from 100 to 0. When 0 is reached, T0 will turn OFF. Here, 100 is equal to a time of 1 second for TOFF, and 10 seconds for TAOFF.