I use an “Industrial IoT Wireless to USB Modem” with an “Industrial Wireless Vibration And Temperature Sensor”. The whole thing refused to work for a long time until I discovered the cause:
Every time I disconnect the modem from the power, it falls into a state of deep sleep. The only way to restart the modem is to reset it by connecting pins 5 and 10 of the Xbee module with a wire jumper. This means that I have to reset the modem every time the power goes out.
You will agree with me that this is not ideal in an industrial context where reliability is very important.
Does anyone have any idea what causes this behaviour? Is that normal?
Thank you in advance for your help!