Describe the similarities and differences of the Allen-Bradley Logix5000 Timer and the Allen-Bradley timers discussed in the text.

Question

What will be an ideal response?

Answer 1

Retentive timers (RTO) can be programmed to replace motor-driven timers. The retentive timer lets the timer START and STOP without resetting the accumulated value to 0. The bits associated with the timer EN, TT, and DN function the same as with the TON instruction.

The same EN, DN, and TT bits are available on the Logix5000 timers as was available on the other Allen-Bradley timers discussed in the text. The operation of the TON, TOF, and RTO timers are the same in both types of processors and the same timing charts can be applied to both. The only difference between the timers is the Logix5000 timers have a fixed time base of 1 msec. and use a tag structure to address the timer.