Syd

Ken, thanks for the reply. Here is the test program. Today we found out that the analog input modules are somehow affecting the CPU...even one-shot rising logic failed to trigger. The rack has 2-8 channel AB analog inputs and 2-4 channel AB analog outputs in slots 1 through 4 respectively, along with a host of digital modules and an expansion rack on the SLC backplane cable. Removing both of the 8 channel analog cards caused the program to run okay. Adding one card back in caused the program to run slowly. Adding a single 4 channel input card was okay...adding a second 4 channel input card and program ran slowly. Adding one card in the main rack and a second in the slave rack also resulted in slow running program. Note that the test program has no logic for the analog cards, they are just declared in the I/O structure and sitting there. Yes, they will be required by the rest of the machine application. Any suggestions? Jon NEIL_WORKING_OCT02.RSS

I have project involving several RS485 weigh scale modules communicating to a SLC 5/05 processor. The application is up and working, however the ascii read (ARD) instruction does not seem to pick up the response characters properly from the scale unit. If the weigh scale units are told to delay 1/4 second before sending the response message back to the PLC everything works well. If I make the delay smaller, or remove it entirely, the PLC seems to miss the incoming message. Obviously with 9 scales at 1/4second delay each, this is unacceptable. Anyone seen this type of problem or have suggestions? The application has only one clear buffer instruction (clears both TX&RX). It is sent during the initialization before each write operation to poll the scales. Sydney

I am looking for control/compact logix sample code for either a loss in weight or a gain in weight process. Nothing exists in the download sites I have visited. I don't care about the scale interface type, just the sequence of steps/operations so I do not have to reinvent the wheel. My project will use compact logix and PV+

JC, thanks for this...I did not know if it would be that simple, or if the use of OP15 unit meant the port would no longer respond to PC interface. The last thing I wanted to do was damage a running machine with obsolete controls. Thanks again.

I am new to S5, and have been trying to find info about how I can connect a pc to an SI1 port on S5-095U plc where the SI1 port is already being used to communicate to OP15 operator interface. I have read most of the manuals available, but can not find anything close to explanation. I have the RS232/TTY cable and S5 software. Any help would be appreciated.