A
We recently ran into an unusual problem converting
a program from a SLC5/04 to a PLC-5/11 and was wondering if anyone else has encountered this issue. Perhaps someone knows the reason for the problem and has found a solution.
Hardware:
PLC-5/11, PanelView1000-keypad only, connected via DH+
Software:
RSLOGIX-5, version 3.22.00, PanelView firmware v.3.4
An original program used on a SLC-5/04 was converted to PLC-5/11 by cutting and pasting the ladders and manually converting all necessary commands to their PLC-5 equivalents.
Symptoms:
The FLL (filefill) command is used to turn HMI bits off at end of scan. This operates correctly so long as the ladders do not exceed 7 and total memory use does not exceed 5000kb. If either of these is exceeded, the pushbutton operation of the PanelView begins to degrade and eventually ceases. All reading operations and numeric entry are unaffected and work properly. Only the writing of bits to the PLC are affected.
The JSR command apparently contributes to this problem. If they are removed, the pushbuttons operate normally again.
Our Solution:
After experimenting with the system and observing the scan times, it was clear something was causing the processor to slow down drastically. (This is how we saw the JSR command was part of the problem.)
Using the MCP screen, the subroutines are called via configuration instead of by coding. This replaces the need for using JSR commands. The application now works properly.
Question:
Since we are unfamiliar with all the nuances of the MCP, can anyone confirm that it forces the servicing of I/O? We rarely make conversions between SLC-5/04 and PLC-5/family softwares. Are
there issues at work here that are not well documented?
Any other insights are greatly appreciated. I can be contacted personally at the address below if you require more information.
Best regards,
Ruel V. Alejaga
Systems Engineer
E-mail:[email protected]
Control Masters, Inc. Voice: 630-968-2390 x309
5235 Katrine Avenue FAX: 630-968-3260
Downers Grove, IL 60515
a program from a SLC5/04 to a PLC-5/11 and was wondering if anyone else has encountered this issue. Perhaps someone knows the reason for the problem and has found a solution.
Hardware:
PLC-5/11, PanelView1000-keypad only, connected via DH+
Software:
RSLOGIX-5, version 3.22.00, PanelView firmware v.3.4
An original program used on a SLC-5/04 was converted to PLC-5/11 by cutting and pasting the ladders and manually converting all necessary commands to their PLC-5 equivalents.
Symptoms:
The FLL (filefill) command is used to turn HMI bits off at end of scan. This operates correctly so long as the ladders do not exceed 7 and total memory use does not exceed 5000kb. If either of these is exceeded, the pushbutton operation of the PanelView begins to degrade and eventually ceases. All reading operations and numeric entry are unaffected and work properly. Only the writing of bits to the PLC are affected.
The JSR command apparently contributes to this problem. If they are removed, the pushbuttons operate normally again.
Our Solution:
After experimenting with the system and observing the scan times, it was clear something was causing the processor to slow down drastically. (This is how we saw the JSR command was part of the problem.)
Using the MCP screen, the subroutines are called via configuration instead of by coding. This replaces the need for using JSR commands. The application now works properly.
Question:
Since we are unfamiliar with all the nuances of the MCP, can anyone confirm that it forces the servicing of I/O? We rarely make conversions between SLC-5/04 and PLC-5/family softwares. Are
there issues at work here that are not well documented?
Any other insights are greatly appreciated. I can be contacted personally at the address below if you require more information.
Best regards,
Ruel V. Alejaga
Systems Engineer
E-mail:[email protected]
Control Masters, Inc. Voice: 630-968-2390 x309
5235 Katrine Avenue FAX: 630-968-3260
Downers Grove, IL 60515