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LSB
June 21st, 2004, 11:45 AM
Regarding DeviceNet programming, the manual doesn't have much with regards to DNet. It's a pretty simple feet/minute application (and only about 380 fpm max) where I am hoping to use the data to feed back to an infeed belt. My numbers are very inconsistent and I know I am doing something wrong. Using a quadrature encoder. A programming example would be perfect. Thanks

Ken Roach
June 21st, 2004, 12:26 PM
For those of you playing along at home, the 1794-ID2 is a two-channel 24 VDC encoder input module for the FLEX I/O modular I/O system from Allen-Bradley. You can connect FLEX to many different network adapters, including the 1794-ADN DeviceNet adapter.

LSB, your problem statement is pretty vague: "My numbers are very inconsistent" doesn't tell us much.

Chapter 5 of the User Manual is dedicated to the mapping of the module data to a PLC scanner using DeviceNet.

What you need is configuration help, not programming help. Start by posting more information about your configuration of the module (and the rest of the DeviceNet system, like the scanner and the other FLEX modules) and maybe someone on the Forum can help.

My first question is: At 380 feet/minute, how many counts per second is the module getting from the encoder ? You will need to know the mechanical ratio from your conveyor to the encoder as well as the counts/rev value of the encoder.

That answer will help you calculate the Filter Constant setting for the module.

LSB
June 21st, 2004, 12:38 PM
Sorry! Wasn't trying to be vague, I was just fishing to see if anyone knew where there might be more documentation. I'm going to go back and take a look at my config's and will report back. Was maybe looking for a shortcut as this is just 1 of 10 things on the go right now. Thanks for the reply!!

LSB
June 21st, 2004, 12:46 PM
Sorry! Wasn't trying to be vague, I was just fishing to see if anyone knew where there might be more documentation. I'm going to go back and take a look at my config's and will report back. Was maybe looking for a shortcut as this is just 1 of 10 things on the go right now. Thanks for the reply!!

lexarius
June 20th, 2006, 10:46 AM
I've got some problem trying to get any readings from SMC stroke reading cylinder using 1794 ID2(Series B) module.
My configuration is SLC 5/04 1747 SN scanner SMC EX500 Gateway unit (for remote I/O). I've used BTR and BTW instructions to control the module but I can not get any readings.
I really appreciate your help.
Sorry if it's wrong post. I've registered just today and I never used this forum.