I am in the process of installing a Power Management system in for one of our precipitators. The vendors from the PMS controllers tell me that I can send/receive data from my DCS system [Foxboro] to the T/R set controllers via the PLCs. I believe that in order for me to be able to connect to the controllers I need a PLC Basic Module. Can anyone tell me what is the difference betweeen a PLC-5 Basic Module and a normal module? I would really appreciate the input.

Thanks,
PowerMan

 

PowerMan,

There is no such thing as a normal module. Every module made for the PLC-5 (to fit the 1771 racks) is special in that it is made for specific I/O and data handling. If by normal module you mean a module simply scanned by the
I/O scanner or processor, then yes the Basic module is a bit more than normal. It requires block transfer (read/write) to get data to and from it. The data you move to and from the module in 64 word chunks (the limit of the
block transfer). In the module you can perform any sort of processing via the Basic programming language. The module has two RS-232 ports for connection to the outside world (usually the second port is used for printers). A lot of people will tell you the module is slow, but it is simply a function of how you set up the data transfer (there is double buffering between the I/O backplane and the basic processor in both directions) and the amount (and method) of programming on board the module. I have used the module for protocol conversion, to talk to scales, for vibration monitoring, for power monitoring and for special operator
interfaces. It works fine.

Happy New Year to all!

Hugo
Rockwell Solution Provider
http://www.plc-control.com


On January 2, 2004, PowerMan wrote:
> I am in the process of installing a Power Management system in for one of
our precipitators. The vendors from the PMS controllers tell me that I can
send/receive data from my DCS system [Foxboro] to the T/R set controllers
via the PLCs. I believe that in order for me to be able to connect to the
controllers I need a PLC Basic Module. Can anyone tell me what is the
difference betweeen a PLC-5 Basic Module and a normal module? I would
really appreciate the input. <

 

There is no "what you called normal module on PLC-5". I think you are comparing digital and/or analog IO's against the basic module. The basic module is classified as a communication module. I think your vendor is saying is true however, you will need somebody who can adapt and make program from your PLC-5 to the basic module and to the controllers.I had used it once using Honeywell controllers and it work.