wilsonzhu Member W Join Date Jan 2008 Location vancouver Posts 278 Dec 9, 2008 #1 Hi all, I tried to test the watchdog timer in PLC5-20/E. When I set watchdog timer to 0, CPU still running. Does watchdog time has the low limit? Because I did somthing in SLC500, the CPU will be fault at once. What is the probleum? Thanks a lot !
Hi all, I tried to test the watchdog timer in PLC5-20/E. When I set watchdog timer to 0, CPU still running. Does watchdog time has the low limit? Because I did somthing in SLC500, the CPU will be fault at once. What is the probleum? Thanks a lot !
rdrast Lifetime Supporting Member Join Date Apr 2003 Location South Carolina Lowcountry Posts 5,544 Dec 9, 2008 #2 Just make an infinite loop.
wilsonzhu Member OP W Join Date Jan 2008 Location vancouver Posts 278 Dec 9, 2008 #3 Actually there is a program running in PLC5, its scan time is about 6 ms.
TConnolly Lifetime Supporting Member Join Date Apr 2005 Location Salt Lake City Posts 6,152 Dec 9, 2008 #4 According to the PLC5 manual, even though Logix5 allows you to enter single digit watchdog times, the minimum watchdog time is 10 milliseconds. Use an infinite loop. Q2:1 Q2:1 ----[lbl]----------<JMP>-- Edit: if a fault routine is defined it could be running and clearing the fault, then resuming the program. Last edited: Dec 9, 2008
According to the PLC5 manual, even though Logix5 allows you to enter single digit watchdog times, the minimum watchdog time is 10 milliseconds. Use an infinite loop. Q2:1 Q2:1 ----[lbl]----------<JMP>-- Edit: if a fault routine is defined it could be running and clearing the fault, then resuming the program.