retentive timers

Anyone please
Whats the different between the retentive and non-retentive timers

Hello akumar;

A non-retentive timer's accumulator will reset when the enabling input is reset; the next time the enabling bit is set, the timer starts at zero value (it times the full value of the preset, if the enabling bit is set longer than the preset).
A retentive timer's accumulator will not be reset when the enabling bit is reset, only when the timer's reset input is enabled, or when the timer is done. When the timer's enabling bit is first reset, and then set, it restarts at the last value on the accumulator.
Hope this helps,
Daniel Chartier

so that means TON and TOF are non-retentve timers

Hello akumar;

Yes, and RTO (Retentive Timer ON) is a retentive timer...
Daniel Chartier

thanks Daniel Chartier