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Connection troubles in existing installation - Druckversion

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Connection troubles in existing installation - splatch - 06.05.2018

Hi all,
I have a problem with existing installation which worked without any interruption for several months. I had initially some wiring issues, but thanks to Mr. Mariusz from LCN Polen we got it solved. Installation was stable since then. I'm posting this message under bus modules category because it affects multiple software products but its likely a wiring or some sort of hardware issue.

Almost two weeks ago I got issue with two modules (or one, can't remember now), reporting errors. Their buzzer was making noise every couple of seconds. Both modules are located in same point. One handles GT, another push buttons over T8. I restarted whole installation and they got quiet for a bit. After two days I realised that integration going over PKU doesn't work. I checked PCHK logs and found following error:

<LogEntry timeStamp="2018-04-24T09:56:46" component="lcnsession" code="0" isFatal="false">Warning: Buffer is full. Packet was dropped (PacketSessionStateInit::HandleInputPacket).</LogEntry>

Same message was repeated multiple times. I stopped PCHK and started it back. When I tried to connect over PCHK modules which reported issues initially started to report errors again. I was trying to connect with PRO using USB connection, but it doesn't work too. When I disable modules and try to get USB connection even with rail mounted part of installation it fails with error "no connection to LCN installation".

When I monitor USB connection I see traffic. I'm not sure how monitor tracks this and if it uses proper baud rate, but below is just showing that something happens on computer side:
00 00 00 00 00 00 FF
88 04 CD 00 11 16 DF 00
88 06 6A 00 04 68 40 00
00 00 00 00 00 00 FF

Today I disconnected problematic modules but problem remains. Could you please suggest how to approach this problem and how to trace issue?


RE: Connection troubles in existing installation - Sven - 28.05.2018

Hi splatch,
It seems that no one can follow what you mean exactly.
Is the problem already fixed or not?
If not, here are my following steps I would do to find the error:
You need to know which modules are mistaken. For this, take the LCN-Pro with a real coupler without PCHK.  In Busmonitor there has to be something showing what modules are mistaken. After that Cut the data LCN Wire from the modules which are maybe mistaken from the rest of the LCN Bussystem. If the modules are UPP ore Modules with “real” Power Outputs look if they work in the room as “single” Modules without the rest of the system. After that please  look if the rest of the system is working.
It seems if the neutral cable is connected somewhere with the Data wire from LCN. But I think it could be only a module, because the system works a long time as you describe.
It would be also good if you know the firmware of the mistaken modules. Maybe there is a problem which is already known from the hotline of LCN.  I hope the hotline already answers you in an Email and because of this they didn’t answer here. Normal they answer really quick to fix problems like this.
Did you use another system for LCN connection like DOMIQ ?
You can contact me also with an email and we try to fix the problem together.
Greats Sven

RE: Connection troubles in existing installation - splatch - 28.05.2018

Hi Sven,
Thank you very much for answer. I contacted local office and described symptoms. Based on what I described (lack of any activity shown in bus monitor after connecting PRO) their suggestion was that PKU is likely burnt/dead. I took it away from installation and placed in small circuit I have prepared for watering. It is disconnected from main installation. I had no luck and PRO couldn't connect and detect any modules and bus monitor was not showing any activity.
This confirmed that something is wrong with PKU. The day when I noticed troubles with PCHK there was power outage and our operator decided to play a little bit with plug by switching it on and off couple of times before bringing electicitiy back.

I delivered PKU to local distributor and it was sent for additional diagnosis. I'm waiting for their results. I don't use DOMIQ as I was able to get everything with OpeHab which connects several systems for me (zwave, ebus, bacnet, modbus and alarm plus some ikea bulbs added lately ;-)).

Kind regards,