How is it determined if the “net is down for more than 4 minutes”?

I’m polling the unit every 20-30 seconds over the LAN and that works fine with no gaps until the reboot happens. In the logs I pasted to the forum, you can see the timestamps:

Sat Mar 25 02:32:26 EDT 2017
{“data”:{ “id”:”11000103″,”type”:”1″,”detector”:”SBM20″,”voltage”:378,”cpm”:14,”temperature”:30.25,”uptime”: 1026}}
Sat Mar 25 02:32:53 EDT 2017
{“data”:{ “id”:”11000103″,”type”:”1″,”detector”:”SBM20″,”voltage”:376,”cpm”:0,”temperature”:30.25,”uptime”: 15}}

Poll at 02:32:26 . Reboot about 12 seconds later. Poll at 02:32:53.

There was no loss of LAN connectivity.