TRM250 - Receive SMS & Change Com-port

Networking Solutions
1

Hi,

I have a scadasoftware at several sites. This software has a program that send out alarm to personell via sms. The personell can also answer to this alarm sms via sms to acknowledge the alarm in the scada. Before with the old 2G/3G modem it was possible. In Sweden they are shutting down this nets and therefore i bought TRM250 4G to replaced the old ones.

The problem we have now is:

  • It is not possible to receive SMS anymore (send acknowledge back to the modem). Do I have to make some setting in the modem via AT-commands?
  • When you install the modem via USB we get a Com-port for this in windows. Sometimes it changes to another com-port by itself. We can not say when and when I test fex to restart windows then it keep the Com-port. The problem when it changes Com-port is that then the software can’t find it anymore because we put in the fixed Com-port in this settings. The result is that NO alarm is called out and this is a big problem.
3

Hello,

  1. Ensure you’ve followed & completed all of the steps listed here: TRM250 First Start - Teltonika Networks Wiki
  2. Full AT command list can be found here: TRM250 AT Commands - Teltonika Networks Wiki
  3. Additional setup shouldn’t be required if all the steps you’ve done were completed from step 1
  4. The particular command (and ensure you’re using this correctly) to send an SMS message is AT+CMGS; More information within the documentation: https://wiki.teltonika-networks.com/images/4/48/Quectel_BG96_AT_Commands_Manual_V2.3.pdf#page=140&zoom=100,68,97

This sounds either like a Windows-related issue or a cable-related issue. COM ports don’t usually change, unless disconnections happen, and keep happening, could also be the reason as to why issue no. 1 is happening. I’d suggest trying to re-install the drivers, trying a different cable, and potentially, even a different computer.

Regards,
M.