Comfort  Automation/ Security System Forums Home
Home Search search Menu menu Not logged in - Login | Register

Slave 1 and Slave 2 comm failure Help
 Moderated by: slychiu
 New Topic   Reply   Printer Friendly 
 Rate Topic 
AuthorPost
 Posted: Tuesday Mar 17th, 2015 10:39 pm
   PM  Quote  Reply 
1st Post
TheMax74
Member


Joined: Monday Jul 16th, 2007
Location: Italy
Posts: 247
Status: 
Offline

  back to top

Hello, i've suddenly experienced a communication failure for slave 1 and then for slave 2.I've already checked and tight all ID jumpers on all slaves and UCMs.From the keyboard i heard "Communication Error, 34".See also the screenshot attached.The Comm failure for both slaves and the comm restore continue forever.The green LEDs on both slaves stay on, then flash once, then i hear the Comm failure alarm. Any advice on how to solve this? 
Some advices: Slave 2 is connected via the 4 pole cable to the Slave 1.  Slave 1 is connected to the main board via the KA KB 2 pole connector.  Slave 1 has its own battery and transformer and powers Slave 2 too.

Below, the log:
03/17 13:58 ....all normal before, then:
03/17 14:13 Comm. failure # Slave 1
03/17 14:13 Comm. failure # Slave 2
03/17 14:13 Alarm Type # RS485Comms (24)
03/17 14:13 Sign in - User # 1
03/17 14:13 Sign in - User # 1
03/17 14:14 Comm. restore # Slave 1
03/17 14:15 Comm. failure # Slave 1
03/17 14:15 Alarm Type # RS485Comms (24)
03/17 14:15 Comm. restore # Slave 1
03/17 14:16 Comm. failure # Slave 1
03/17 14:16 Alarm Type # RS485Comms (24)
03/17 14:23 Comm. restore # Slave 2
03/17 14:23 Comm. failure # Slave 2
03/17 14:23 Alarm Type # RS485Comms (24)
03/17 14:24 Comm. restore # Slave 1
03/17 14:24 Comm. failure # Slave 1
03/17 14:24 Alarm Type # RS485Comms (24)
03/17 14:25 Comm. restore # Slave 1
....repeating forever.

Attachment: Screenshot.jpg (Downloaded 28 times)

Last edited on Tuesday Mar 17th, 2015 11:31 pm by TheMax74



 Posted: Wednesday Mar 18th, 2015 06:13 am
   PM  Quote  Reply 
2nd Post
slychiu
Administrator


Joined: Saturday Apr 29th, 2006
Location: Singapore
Posts: 5493
Status: 
Offline

  back to top

It could be because one of the slaves has developed a fault in the rs485 driver
Try disconnecting a slave and see if the problem stops, ie you wil get a permanent comms failkure because of the disconnected slave
This is to identify which slave causes the problem



 Posted: Wednesday Mar 18th, 2015 10:00 am
   PM  Quote  Reply 
3rd Post
TheMax74
Member


Joined: Monday Jul 16th, 2007
Location: Italy
Posts: 247
Status: 
Offline

  back to top

Hi Chiu.
Connecting one slave at a time to the main board changes nothing. Both seems to have problems.
But... Connecting one slave at a time to the main board using the 4 pole cable instead of the KA KB 2 pole connection, seems to solve the issue. Both slaves works.
It is strange, because the keypads works flawlessy with KA KB cable.



 Posted: Wednesday Mar 18th, 2015 10:37 am
   PM  Quote  Reply 
4th Post
slychiu
Administrator


Joined: Saturday Apr 29th, 2006
Location: Singapore
Posts: 5493
Status: 
Offline

  back to top

There may be a partial short on the ka kb wires
Disconnect and measure resistance between them



 Posted: Wednesday Mar 18th, 2015 05:48 pm
   PM  Quote  Reply 
5th Post
TheMax74
Member


Joined: Monday Jul 16th, 2007
Location: Italy
Posts: 247
Status: 
Offline

  back to top

Hi Chiu,
for now, i solved by re-wiring a "COM" cable (the negative pole of the 12V power socket) between Slave 1, Slave 2 and Main board.
For an unknown reason, this wire was come out from the socket of the Main board.
I've been restored the connection through KA KB cable and both slaves seems to work normally now.

By looking closely to the wire, i'm sure that for a long period of time, the connection was ok, even without the negative ground connecting all slaves and the Main board.
Is that possible?



 Posted: Sunday Mar 22nd, 2015 01:13 pm
   PM  Quote  Reply 
6th Post
slychiu
Administrator


Joined: Saturday Apr 29th, 2006
Location: Singapore
Posts: 5493
Status: 
Offline

  back to top

It is possible that the communication can work even without the COM cable but it may be intermittent



 Current time is 07:12 pm
Top




UltraBB 1.172 Copyright © 2007-2014 Data 1 Systems