AB Micro Logix 1500 Timer Question


Thread Starter

Pete Arthur

I am working on a project using an AB MicroLogix 1500, and PView 300 terminal. I am using RSLogix 500 software.
I have used timers before, and have successfully shown time on the panel, but it is always "counting up". I need to show the time currently set in the Timer PRE register, but rather than showing the Timer ACC, I need to show it counting down instead. Any ideas??

Pete Arthur
Emerson Drive Solutions
> Simple !

Use SUB block. Subtract T4:0.acc from T4:0.pre, and place result in N7:0. Display N7:0 on the Panel View. N7:0 will be equal to time remaining in timer. Of course you can use whatever timer and integer register you want - I just used T4:0 and N7:0 as an example.

Hope this helps ...

Best regards, Bob

Larry Lawver


In RSLogix500, add the following one instruction rung (assuming timer T4:0 and destination register N7:0...

SUB T4:0.PRE T4:0.ACC N7:0

You can copy that from this email and paste it into RSL500. The result in run mode will be a down count in N7:0, which you can then associate
with a display tag on the PV300.

Hope this helps!

Larry Lawver
Rexel / Central Florida

Dobrowolski, Jacek

How about subtracting T?.PRE - T?.ACC ?

Jacek Dobrowolski

Software Eng.
Automation Department
Secondary Division
International Tobacco Machinery Ltd. POLAND
mailto: [email protected]