One threshold can't serve both kinds of unit. Applying the Wi-Fi one to cellular units would mark every healthy cellular unit permanently disconnected; applying the cellular one to Wi-Fi units would hide a real outage for half an hour.
For a cellular unit the threshold follows that unit's own reporting schedule rather than a fixed number of minutes. So a store that hands over hourly overnight is not flagged at 2am for being exactly as quiet as it was told to be, and one that hands over every five minutes is still flagged quickly if it goes silent.
| Wi-Fi | Cellular | |
|---|---|---|
| Reports | Continuously | In batches, on a sync schedule |
| Dashboard says | Last seen | Last synced |
| Counts as offline after | A few missed reports — minutes | Several missed syncs — tens of minutes |
A cellular unit also syncs when something happens, not just when a timer goes off. If the heat level changes, or conditions are climbing fast, it reports within a couple of minutes rather than waiting. So a longer gap between syncs is a statement that nothing has changed — not that the unit is behind.
- It measures every couple of seconds either way, and keeps a row every five minutes. A quiet sync schedule costs you no resolution in the record.
- The unit's own screen is always current, whatever the dashboard last heard. On-site safety never waits for a sync.
- The gap is a setting, so it can be tightened for a site that warrants closer watching, or relaxed for one that doesn't.
When several units go quiet at once, the notice arrives as one email listing them — longest-quiet first — rather than one email per unit. That is usually the honest description of what happened: one network or carrier problem, not twenty separate faults.
- In an organisation it goes to everyone who can administer it, not only to whoever created the account.
- A store's own alert number is still texted about its own sensor, separately. Nobody is told about somebody else's store by text.
- It says plainly that the location has no heat monitoring while the sensor is quiet, because that is the part that decides whether somebody deals with it today.