Schneider HSBY, standby PLC goes offline

Hello everyone!
Having a hot standby with H5724M system , I am randomly getting the following errors on the standby PLC:

• Message : HSBY: Switch from Standby to Offline
  Symbol : Offline command register request
  16#32D6 , 13014
• Message : Switch from Offline to Standby
  Symbol : Hot standby
  16#32DA , 13018

The hardware configuration is as follows:

1. PSY3610M
2. H5724M
3. ETY4103 (connecting PLC rack with RIO drop through a Schneider electric network switch)
4. ETY4103 (connecting PLC rack with local network through another network switch)

The topological address of the monitored Ethernet module is : Rack Slot 0.3 , i.e ETY4103 connected to RIO drop as shown in the attached image.

The error messages appear randomly, however they seem to get more frequent until the standby PLC goes offline and does not recover. This increase in errors sounds like networking problem especially on the network switch connecting PLC with RIO drop but I would love to hear your opinions as I am not able to fix the issue.

I would really appreciate any comments !

Also let me know if you need further information on my setup.

Thank you in advance

Best Regards

atomtm said:

Hello everyone!
Having a hot standby with H5724M system , I am randomly getting the following errors on the standby PLC:

• Message : HSBY: Switch from Standby to Offline
  Symbol : Offline command register request
  16#32D6 , 13014
• Message : Switch from Offline to Standby
  Symbol : Hot standby
  16#32DA , 13018

The hardware configuration is as follows:

1. PSY3610M
2. H5724M
3. ETY4103 (connecting PLC rack with RIO drop through a Schneider electric network switch)
4. ETY4103 (connecting PLC rack with local network through another network switch)

The topological address of the monitored Ethernet module is : Rack Slot 0.3 , i.e ETY4103 connected to RIO drop as shown in the attached image.

The error messages appear randomly, however they seem to get more frequent until the standby PLC goes offline and does not recover. This increase in errors sounds like networking problem especially on the network switch connecting PLC with RIO drop but I would love to hear your opinions as I am not able to fix the issue.

I would really appreciate any comments !

Also let me know if you need further information on my setup.

Thank you in advance

Best Regards

Click to expand...

The first thing i would check is the current version of firmware, in one of the updates there was a lot of fixes for stability of Premium processors, also update the ETY modules at the same time if you can

And the Premium is now dead! LOL Lot of people caught short as it happened fairly quickly. I got caught out.

BobB said:

And the Premium is now dead! LOL Lot of people caught short as it happened fairly quickly. I got caught out.

Click to expand...

Yep, we were caught out on a couple of projects too, we are yet to do a Premium to M580 conversion, i ran a fairly complex application through their UMAC tool and it didn't look pretty....

They also canned the Advantys OTB without mentioning it to us.

Thank you all for your replies!

@tragically1969 what do you mean by updating the ETY modules please?
Also I forgot to mention that while the problem occurs, I am not able to connect to the standby processor using Unity Pro and TCP/IP connection.
Also this problem appeared all of the sudden , while the project was working fine for very long time (4-5 years now)

atomtm said:

Thank you all for your replies!

@tragically1969 what do you mean by updating the ETY modules please?
Also I forgot to mention that while the problem occurs, I am not able to connect to the standby processor using Unity Pro and TCP/IP connection.
Also this problem appeared all of the sudden , while the project was working fine for very long time (4-5 years now)

Click to expand...

Are you connecting to the standby through the network switch or direct ?

You can update the firmware in the ETY modules, but to be honest if its only started doing it recently then it sounds like a failure, either in the PLC or the network.

I am trying to connect remotely (off-site) through the network switch.

What you say is true, i.e since it started all of the sudden it sounds like a failure. However the Diagnostic Viewer does not give more info than the messages I posted on my first post.



So I was thinking if you have an idea, how to further analyze and troubleshoot the issue. Most difficult part is to recreate it. From online resources (can't recall the source) I found that a CPU goes to offline mode if it loses connection to its RIO connection (is this even correct?) so this is why I am suspecting the network switch connecting the RIO DROP.



Any thoughts please?

If you look Premium Hot Standby with Unity User Manual
(https://damrexelprod.blob.core.windows.net/medias/f530a675-9bdb-4016-8021-3940f41e4d98)
page 138, it says that logic code mismatch is only selectable on quantum PLCs.
Also on end of manual is commo errors mentioned.



Also you should look %SW61, no %SW60. (%SW60 is copied from primary to standby, and can used for swapping prmary PLC to standby)



So it can be defective power supply, rack, CPU hardware or ETY cards (slot 3 card probably as it is monitored).



Change first power card, if error still exist. Change original power supply back and swap ety cards 3 and 4.
If proble goes away, then it is ety card on slot3.)


If still, then replace rack (TSC RKYx).
If still errors, then CPU is defective, I think.


Defective switch, not sure if its even faults standby.




Also H57 premium didn't swap automatically CPU if RIO drop is lost. Swapping is done on somewhere on PLC program. Standby PLC can't swap PLCs, so are you sure that error is coming from standby.

(PLC IP addresses are swapped on swap, so you see only which one is standby and which is primary on PLC run leds. (if there isn't code on PLC which determines which is primary and which is standby).

Thank you @Lare.

Could you please explain your thoughts on the defective switch ?
I was thinking about the network switch because if it's faulty then the ETY connected would not function correctly .What are your thoughts ?

It is more like some 5-8 years when tested.
But page 263, https://damrexelprod.blob.core.windows.net/medias/f530a675-9bdb-4016-8021-3940f41e4d98


Pretty surre that if primary PLC losted communication to standby (RJ45 removed from monitored ETY), PLC are swapped.


But if standby PLC lost coms, standby is changed to offline and again to standby if communication is established again.


So if your switch have defective port it probably can make errors (or ETY card is defective, which you see if you swap modules on rack,. Whit crossover cable you probably would have both CPUs running as primary or stopped if partner ETY port is faulted?)

Defective powers do some weird things also, as CPU cold starts rapidly.

This is very informative and helpful @Lare !

I really really appreciate this. Thank you.