Host Engineering Forum
General Category => Do-more CPUs and Do-more Designer Software => Topic started by: brucek on January 14, 2020, 09:31:51 AM
-
Yesterday was able to play with the plc and drive to check things out for the first time. I didn't have the parameters for comm card issue set so if i unplugged the Ethernet cable the drive continued to run. Found the parameters for that and made that time out 2 seconds, works well.
My Question is if the PLC goes into Program mode because of a error and the drive is running what tells it to stop? The cable would still be plugged in but maybe that would not communicate and would act in the same way or because the cable is plugged in there is no error for the comm card.
I'm sure a lot of you use modbus but this is my first attempt so I'm not sure what the proper way to deal with this is. Does the DoMore finish with Last scan even if it is a PLC errors or does it stop immediately? I'm hoping its as simple as adding a stop to the last scan task to make sure the drives stop.
Any clarification would be helpful.
-
Are you using the GSEDRV100 card? If so, set it up as Ethernet I/O Slave (NOT EtherNet/IP - that is something completely different). The PLC handles all the comm intelligently as part of the "native" PLC I/O and sticks the critical GS drive parameters into its own GSDrv structure (e.g. GSDrv.Direction bit). Because it's treated as PLC I/O, the GSEDRV100 handles mode changes properly. No ladder logic to write. No Modbus instructions (although there are GSREGRD and GSREGWR instructions that do Modbus behind-the-scenes for reading/writing any of the Px.x parameters)
If you are doing it "by hand" (i.e. no GSEDRV100 card), I think there might be a "run" relay you could hard-wire from the PLC to the drive? ? ? Sadly, you can't do a comm request in the "last scan". When the PLC goes to STOP/PGM mode - it can't execute any ladder logic. If you hard wire the "run" relay to the PLC, Y's automatically turn OFF when the PLC goes to PGM mode.
-
Thank you for the reply franji but atm I'm not using the GS-EDRV100 but if this is unsafe then I will have to start. This might be more of a drive question then a PLC question.
This is from the gs4 manual. i have 9.93 set to 2 and 9.94 set to 1 and 9.95 set to 2.0. I'll have to try it but does shutting down the mwx and mrx commands stop communication so that it times out? not sure about overhead communications where they will still be wired but if nothing is going out over the line I'm hoping its like pulling the cord out of the switch. Otherwise I'll look if I can run a relay for the enable and still use comm card for remote speed and control.
P9.93 Ethernet Communication Card Fault Select ♦ R/W 095D 42398
Range/Units (Format: 16-bit binary) Default
0: Warn & Continue Operation
1: Warn & Ramp to Stop
2: Warn & Coast to Stop
3: No Warning & Continue Operation
3
This parameter is used to detect an Ethernet communication error and take appropriate action.
Related Parameters: P9.94, P9.95
P9.94 Ethernet Communication Card Time Out Detection ♦ R/W 095E 42399
Range/Units (Format: 16-bit binary) Default
0: Disable
1: Enable
0
This parameter Enables or Disables time-out detection for Ethernet communications.
Related Parameters: P9.93, P9.95
Type Hex Addr Dec Addr
P9.95 Ethernet Communication Card Time Out Duration ♦ R/W 095F 42400
Range/Units (Format: 16-bit unsigned) Default
0.1 to 100.0 seconds 0.5
When parameter P9.94 is set to 1, the communications Time Out Detection is Enabled. If a delay in
communications for more than the Time Out Duration (P9.95) is detected, the action selected by
the Transmission Fault Treatment (P9.93) will be used.
Related Parameters: P9.93, P9.94
-
That looks like it should work, but one of the ADC tech support folks could confirm for sure that it will.