Getting into PSM when not registered on network


We have a customer board based on BG77 (BG77LAR02A04_01.006.00.000).
PSM is working quite well and we prefer this to powerdown as there is a 10uA less current consumption.
However during stress testing we found that if by chance the modem loses network registration due to weak or no network (say the device is on the move and loses registration), then the module does not enter PSM and in fact keeps trying and wastes a lot of battery.
We have worked around this by powering down rather than going to PSM when we detect not registered.
However we do not want to suffer the 10uA penalty as stated above.

So can someone help with some PSM configurations or sequence of commands which will take the module into PSM even if not on the network. We were thinking of commands like QPSMCFG or QPSMEXTCFG but unsure if they will work or what settings to give via these commands.


If the network connection fails or the radio signal coverage is weak, the module will continue to search the network and the camp base station cell, and cannot enter the PSM state for a short time. It is more effective to save power if you take the power off mode