Cannot enter to PSM mode

IoT Modules LPWA Module
2

Hello @MHD

for PSM to work it needs to be supported by the network. And in my experience the network seldom accepts the exact values requested.

Below are the AT commands I am using successfully with my BG95-M3.
(Please note: I am using the Quectel specific AT commands for PSM, eq QPx instead of CPx.)

// Disable PSM
AT+QPSMS=
  OK
// Check PSM - 0 means disabled
AT+QPSMS?
  +QPSMS: 0,,,"14400","20"
  OK
// Enable PSM - ask for 60 s TAU and 30 s active timer
AT+QPSMS=1,,,"01111110","00001111"
  OK
// Check PSM - network agreed to 42 min TAU and 32 s active timer
AT+QPSMS?
  +QPSMS: 1,,,"2520","32"
  OK
// about 32 seconds later modem goes into PSM
  PSM POWER DOWN

Notes:

  • forcing PSM with AT+QCFG="psm/enter",1 does not work for me
  • when the modem is in PSM PSM_IND goes low
  • when the modem is in PSM the netlight also turns off

Thanks
Felix