This forum uses cookies
This forum makes use of cookies to store your login information if you are registered, and your last visit if you are not. Cookies are small text documents stored on your computer; the cookies set by this forum can only be used on this website and pose no security risk. Cookies on this forum also track the specific topics you have read and when you last read them. Please confirm whether you accept or reject these cookies being set.

LogicMachines KNX Rx down after bus power outage
#1
Two days ago my bus power supply decided to quit delivering power.
I restarted the power supply and it was fine again (probably some error mode). But I decided to swap out the powersupply altogether for a new one.

However, since the swap, the LogicMachines (I have two in this system) both function and can Tx (transmit) to the bus... but they both do not receive any KNX telegram anymore. I viewed the KNX bus status, and it only counts Tx, no Rx in days on both of them.

All other KNX devices in the system (there are 50) still work Tx and Rx. Only the LogicMachines stopped. It's a LM 5 Power, and some LM2 or 3 rebranded for HVAC control.
There are no errors in error log. Voltage log from all devices has been normal throughout. No spikes or anything.


What is going on? Can these be a polarity issue? I am pretty sure the polarity is correct.
Can it be the LM's are damaged? Then why did the LM's die and all other devices work?
Reply
#2
What does the KNX status says in LM about KNX? Have you tried rebooting, power down?
Any errors?
Reply
#3
(21.09.2020, 07:33)Daniel. Wrote: What does the KNX status says in LM about KNX? Have you tried rebooting, power down?
Any errors?

I don't know where to find the 'KNX status'. It just says KNX/TP: OK beneath the LM screens.

Also, in Flashsys > Network > KNX statistics, I can see the TP RX/TX count on 0 / 14037 now, the IP RX/TX is 0 / 0 because I have the LM in TP-UART mode.
The only error in the system log is this one: Sep 18 01:00:18 LogicMachine kern.err kernel: [ 0.318733] Warning: unable to open an initial console.

Ofcourse I tried restarting the LM (about 5 times), and I have hard-shutdown the unit (soft shutdown, then removed power for 10 seconds, then powered the unit again).
Reply
#4
The KNX chip receiver part might be damaged.
Reply
#5
(21.09.2020, 08:07)admin Wrote: The KNX chip receiver part might be damaged.

Sure looks like it. So now I have two deaf LogicMachines Smile 

Can I give them a hearing aid? Or do I bury them at a graveyard?
Reply
#6
They will work over IP so adding an interface would keep them alive.
Reply
#7
(21.09.2020, 10:38)Daniel. Wrote: They will work over IP so adding an interface would keep them alive.

Good idea, although the IP communication tends to lose a telegram here and there occasionally.

I really liked the TP connection because it's thrustworthy.
Reply
#8
You could use tunneling, this is over TCP. Should be solid connection.
Reply
#9
(21.09.2020, 10:44)Daniel. Wrote: You could use tunneling, this is over TCP. Should be solid connection.

Yeah, thought of that 5 seconds after posting.... I set up tunneling which works. Smile 

At least it now gets it's data. Funny thing is that once you setup tunneling, it seems to omit the TP-UART right? Since the transmitted values are just on the bus once.
Only downside is having used yet another 2 of 5 total tunneling connections. I already have 2 occupied by a logging and visualisation system. Oh well. Best used KNX/IP router ever.

Weird that only the LM's died. All other KNX units survived....
Reply
#10
You can ship devices to us for repair if you want.
Reply
#11
(21.09.2020, 11:01)admin Wrote: You can ship devices to us for repair if you want.

Yeah I probably will Smile  I'll order a new one to keep the house running in the meantime though Smile 

I just found out that almost all units did not survive the power supply failing: of the 50 or so units, only 6 still receive telegrams.... oops! That is a costly power supply!

Will get another brand for sure.... Smile
Reply


Forum Jump: