Host Engineering Forum

General Category => DirectSOFT => Topic started by: IHeatEm on February 23, 2011, 12:03:26 PM

Title: Newbie Question About Timers
Post by: IHeatEm on February 23, 2011, 12:03:26 PM

Hello everyone I am new to this site. I am making the transition from programming Honeywell HC900's using function block diagrams to programming in ladder logic (and it has not been an easy task to do so).

My question pertains to off delay timers. I currently am working with a system where once I hit a limit switch I would like the motor to run for an additional amount of time then disable the motor from running in that direction anymore.

Any help would be greatly appreciated. I am so used to programming in FBD this is going to take me some time to get a grasp on.

Title: Re: Newbie Question About Timers
Post by: franji1 on February 23, 2011, 02:30:37 PM

If you are using an 05, 06, 250, 260, or 450 CPU, there is an Off Delay Timer instruction OFFDTMR.  This is an OUTPUT column box and its powerflow status into the box is what drives the actual output.  Here's the blurb from the Help system on this instruction:

This IBox will delay turning OFF the specified output by the timer’s preset value. When the input turns ON, the designated output will turn ON. When the input circuit turns OFF, the output will remain ON for the duration of the timer’s preset value, and then the output will turn OFF.
If the input circuit turns ON before the timer expires, the timer will be reset and the output will remain ON.

Title: Re: Newbie Question About Timers
Post by: IHeatEm on February 23, 2011, 04:07:09 PM

Thank you for the help. It worked out. I really need to get familiar with all the functionality there is.