M1 Support Forum Random System Start Up – Input Card

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    Bryan Cargould

      I have a M1 Gold system that been running for 8 months now. Since it was installed there have been random “System Start Up’s” for “Input Exp. 2” reported in the log file. I have not noticed any performance issues or failures of any zones, it’s just like the input card needs to reboot. I have verified the card address is unique and there were no errors when enrolling the card. However, when I perform a system diagnostic there is a Data Bus Error “T2A3 17024″, I have verified the bus wiring to the card and the only thing I can determine is maybe it’s to0 short, about 18”.

      Brad Weeks

        How many total bus devices are connected to the M1 and how are they wired 1) M1DBH, 2) M1DBHR or 3) Daisy Chained? Are there more than two home runs connected to the M1? If using the M1DBH is the overall Data Bus wiring less than 2000 feet or if Daisy Chaining less than 4000 feet? Do you have any secondary power supplies powering bus devices and if so there is a Common DC Negative between the M1 and the secondary power supply? In the case of a secondary power supply the +12V of the M1 should not be connected to the device if using a secondary power supply. With the entire system powered down including any secondary power supplies measure the resistance across Data A and Data B at the M1 Main Board — you should measure ~60-70Ω Ohms. If you measure 120Ω we’re missing a terminating jumper and if less than 40Ω too many terminating jumpers. With the system powered UP measure the voltage at each device. You should measure 12-14 VDC. If less than 12 this could cause issues.


        The M1 System has been designed in that if it detects any operational anomalies, regardless how small or big or the cause it will attempt to “Self-heal Itself” in the most expedient manner. It does this in order to restore itself to a functionally operational state. This event is logged as a System Startup – Control or Bus Device. Has anything changed either with the M1 System or the environment at this location?


        You are currently running M1 Firmware 5.3.14 and  M1G Firmware 5.3.18 is available which has code changes to address and improve System Start-ups which might be occurring. You may want to consider updating the M1 Firmware to see if this makes a difference.

        Bryan Cargould

          The system consists of one home run bus through a M1DBH with 4 keypads, 2 expansion input cards, 1 expansion output card, one UPB interface, and the terminator. None of the keypads or expansion card are using terminating resistors and the measured Bus resistance was 51.1 Ohms with the terminating resistor and 70.5 without.

          The total bus run lengths counting both ways on each run is between 450 and 550 feet total of Cat 6 cable.

          There is a secondary power supply powering the Ethernet interface and the audio card. It is also wired to an input for monitoring only and the negative is connected to the main negative terminal where the battery negative is also connected.

          System Diagnostics reports a Voltage of 13.8 and Current of 0.42 amps, measured voltage is around 13.5.

          Bryan Cargould

            Also, here are the System version that were updated last December I forgot to include,

            M1G – Hardware 0.13, Boot 3.3.6, Firmware 5.3.18, Voice 0.8

            M1XIN – Card 1 – Hardware 0.5, Boot 3.05, Firmware 1.3.7

            M1XIN – Card 2 – Hardware 0.5, Boot 3.05, Firmware 1.3.7


            Brad Weeks

              50Ω Ohms is somewhat low and without the Terminator RJ45 in J8 you should measure ~120Ω —- There should be a jumper across JP3 on the M1 main board. Make sure JP3 on the M1 is in place — power down the M1 System and:

              • Unplug each Bus Devices from the M1DBH
              • Connect the RF45 with built in resistor into J1 on the M1DBH
              • Measure the resistance which should be ~60 – 70Ω
              • If so then move the RJ45 to J2 and connect a device to J1 and measure again
              • Keep repeating this adding another device to the M1DBH and moving the RF45 with Resistor to the next port and measuring the  resistance
              • Each time you should measure between 60 – 70Ω
              Bryan Cargould

                Ok, I did all the testing you outlined above and found that one of the keypads still had the J1 jumper installed. When I removed it and retested the Bus measured at 72.1Ω, which is just outside the range you mentioned but much less than 120Ω and better than the 51Ω I had. I have cleared the log and will monitor it to see if the random startups disappear.

                Thank you for you assistance with this.

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