FX30 Sometimes Will Not Wake from ULPM

I have an FX30 being used in a medical device and it runs an application that uploads log data about the device’s performance periodically, The medical device is used intermittently in various geographic locations and is not always powered on nor is it always in location with cellular coverage when is powered on. Therefore the application on the FX30 has been designed to go into ULPM when there is no coverage then wake periodically and upload the data when coverage is available. The solution must function autonomously w/o any operator intervention.

Here is the scenario and the issue I’m encountering: FX30 Plugged into a Voltaic V50 USB Battery Pack ( https://voltaicsystems.com/v50/ ). This pack is in turn plugged into a PC USB outlet to charge the battery pack when the PC is on. Wrinkle is that the PC is powered by 220V power.

The issue is that the FX30 will only wake from ULPM via timer once or twice as long as the USB battery is plugged into the the PC USB port (doesn’t seem to matter if the PC is on or off). If the battery is NOT plugged into a USB port then the FX30 goes into ULPM and wakes reliably until the battery is discharged. The confusing thing is that it will also sleep (ULPM)/wake reliably if the battery is plugged into the PC and it is powered from 120V AC power. However, this PC is mounted inside a larger piece of medical equipment and I don’t have the option of changing the power supply voltage.

I have the FX30 case grounded to the equipment chassis and have verified it is grounded to the PC case and outer part of USB plug. I’m not an Electrical Engineer but I have a fairly solid grasp of electrical/electronic concepts. I am using firmware SWI9X06Y_02.16.06.00, is this possibly related to the wake on GPIO issue addressed in firmware R11.0.0? Is it possible that this 220V power arrangement is somehow disrupting the FX30’s ULPM wake functionality? Is there anyway to troubleshoot this either using any logs or diagnostic tools on the FX30 or maybe by testing voltage levels inside the FX30 with an oscilloscope while it is ULPM?

Hi david.churchill

Are you using the Legato Timer API or the Legato Power Management tool (pmtool) command to put FX30 into ULPM?

Could you share with me the log file of “logread -f”?

Are you using FX30 CatM R11.0 firmware? It is SWI9X06Y_02.22.04.00 firmware.
https://source.sierrawireless.com/resources/airlink/software_downloads/fx30-firmware/fx30-firmware-catm/#sthash.y7wBQj5o.h9ZxFjJv.dpbs

You can use “logread -f” command to check logs of FX30. You can also use the oscilloscope device to test voltage levels or Otti, Power support Agilent device to test current consumption inside the FX30.

Hi David, just a thought. Most USB power banks go to sleep if the drawn current is below a certain level (depends on the USB power bank). I see these have the option of being “always on”…

Because you are seeing a difference between when plugged into the power bank and when plugged in the PC… I’d check to make sure your power source is not turning off or going to sleep. I had this problem and need to pulse drawing a current every 15seconds to keep my power bank “on”… but yours seems to have a feature to ensure it stays on…

Good luck!