1746-HSCE Allen Bradley STI

[feike2]

Hi, I have a problem with the scan time of my allen bradley 5/05. The scan time is now aboput 13 ms. This scan time is to long for my purpose and I want to use a STI, selectable time interrupt with my Hi Speed Counter Card 1746-HSCE. I want to read the accumelated count I:e.1. Can annyone tell me if this is possible and how I have to do this? Thanx Feike

 

[OkiePC]

How to set up STI

Open the processor status display (under Controller in your project tree). Go to the STI tab. Set the "Setpoint" to the interval you want the STI ladder scanned. Make sure you understand the timebase is *10ms unless you set the "Resolution Select Bit". Enter the "File Number" which will contain the STI logic. Create the STI ladder file, and move your logic there. Download. (Note: you can do this online if you create the ladder file first). Try to keep your STI logic as efficient as possible. Your regular program scan time may now be more erratic than before, depending on how much code is in your STI and the "Setpoint" frequency. This may adversely affect PIDs and other scan time critical code. Understand that the processor will stop IN THE MIDDLE of its regular program scan to execute the STI logic when the time comes. Therefore the STI program will run asynchronously to the rest of the program.

Paul Cunningham

 

[plcman777]

You cannot use an STI with the 1746-HSCE. It runs at it's own scan time dependant of and on the processor.

I think a 5/05 runs this card at 45ms.

You must use the 1746-HSCE2 in order to use an STI