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+--- Thread: Random Communication Failures with Keypads (/thread-5819.html)
Random Communication Failures with Keypads - Howser - 11-11-2025
Since last month (which happens to be when I upgraded all firmware and started using Comfigurator 4.0.3) the alarm panel reports communication failure with keypad 03, which is then reported as resolved a few seconds later.
This morning the alarm panel reported communication failure with keypad 01 and a few seconds later it was reported as resolved.
What could be causing this?
RE: Random Communication Failures with Keypads - slychiu - 11-11-2025
is the keupad power supply connnected to 12V or S12V?
S12V may be switched off by response or time program
casn you read the event logf and check the events that occured around these times?
RE: Random Communication Failures with Keypads - Howser - 11-11-2025
(11-11-2025, 10:01 AM)slychiu Wrote: is the keupad power supply connnected to 12V or S12V?
S12V may be switched off by response or time program
casn you read the event logf and check the events that occured around these times?
The keypads are connected to 12V.
Below is what I got from the event logs...
Quote:11/11 06:25 Sign in - User # 8
11/11 06:25 Mode Change # Security Off
11/11 06:27 Comm. restore # Keypad 1
11/11 06:27 Comm. restore # Keypad 3
11/11 07:01 Comm. failure # Keypad 1
11/11 07:01 Alarm Type # RS485Comms (24)
11/11 07:01 Comm. failure # Keypad 3
11/11 07:01 Alarm Type # RS485Comms (24)
11/11 07:01 Comm. restore # Keypad 1
11/11 07:01 Comm. restore # Keypad 3
11/11 07:30 Comm. failure # Keypad 1
11/11 07:30 Alarm Type # RS485Comms (24)
11/11 07:30 Comm. restore # Keypad 1
RE: Random Communication Failures with Keypads - slychiu - 11-12-2025
I suspect the 12V power supply output to the keypads has malfunctioned and is intermittently dropping the voltage. How old is the Ccomfort, do you have the serial number?
RE: Random Communication Failures with Keypads - Howser - 11-12-2025
(11-12-2025, 02:43 AM)slychiu Wrote: I suspect the 12V power supply output to the keypads has malfunctioned and is intermittently dropping the voltage. How old is the Ccomfort, do you have the serial number?
I upgraded to Comfort II in 2011 and again to CM9001B end of 2019. Comfigurator does not show the serial number, serial number below (from the board)
C095663
RE: Random Communication Failures with Keypads - slychiu - 11-13-2025
It is probably a power supply fault.If the intermittent keypad troubles are annoying you can disable thecomunications failure alarm, by assigning Null alarm to non detector alarm for Rs485 communications failure
see the screenshot
RE: Random Communication Failures with Keypads - slychiu - 11-13-2025
this will prevent the rs485 comms failure from activating, which means you may not be informed of other communications failures.
Maybe you can leave it this way for some time and see what happens
RE: Random Communication Failures with Keypads - Howser - 12-07-2025
(11-13-2025, 01:31 AM)slychiu Wrote: this will prevent the rs485 comms failure from activating, which means you may not be informed of other communications failures.
Maybe you can leave it this way for some time and see what happens
Regarding the power supplier, I swapped power suppliers around and the problem still persist.
RE: Random Communication Failures with Keypads - slychiu - 12-08-2025
Then I suspect the controller CPU board may have a faulty RS485 driver. If you do not want to change the CM9001 , you may want to disable the RS485 Comms failure alarm, in Nondetector alarms, RS485 comms failure set to null This will diosable all comms failure alarms
RE: Random Communication Failures with Keypads - Howser - 12-17-2025
(12-07-2025, 05:25 PM)Howser Wrote:(11-13-2025, 01:31 AM)slychiu Wrote: this will prevent the rs485 comms failure from activating, which means you may not be informed of other communications failures.
Maybe you can leave it this way for some time and see what happens
Regarding the power supplier, I swapped power suppliers around and the problem still persist.
Would the backup battery cause this issue?
Would the comms error trigger an alarm (siren and external monitor trigger) when the alarm is in Away Mode?