opensense
opensense

Quickstart

Pair a Shelly H&T in five minutes

This walkthrough takes about five minutes, assumes you have one Shelly H&T Plus (or a Shelly H&T Gen3) and a phone or laptop on the same WiFi as the sensor. We use Shelly because it is the cheapest commodity sensor that ships with HTTP push out of the box. If you already use another sensor, jump to the Hardware section.

1 · Create the OpenSense account

$ browser
open https://opensense.murzin.digital/signup

Enter your email. You will receive a six-character magic-link code. Paste it into the login screen. No password to remember.

ok
You land on /app/sites with an empty state.
warn
Email arrived in spam.
alarm
No email after 60 s. Check the address; click ‘resend’ at most twice.

2 · Create a site

A site is one physical address: a café, a hotel kitchen, a server room. Reports are scoped per site. Most accounts have one site; chains can have many.

  • Click + NEW SITE.
  • Set Name, e.g. Kava Bratislava.
  • Set Timezone, e.g. Europe/Bratislava. This drives PDF report rendering.
  • Set Vertical to haccp. The vertical configures default thresholds and the report template. You can change it per device later.

3 · Pair the Shelly

  1. Power up the Shelly H&T. The LED blinks blue while it advertises a setup WiFi network named ShellyHT-XXXXXX.
  2. On your laptop, join that WiFi. Open http://192.168.33.1. The Shelly web UI loads.
  3. In Settings → WiFi, configure your real WiFi. Save. The Shelly reboots onto your network.
  4. Find the new IP of the Shelly (router admin page, or the Shelly app, or nmap). Note it down.
  5. In OpenSense, on the empty site, click + ADD DEVICE → SHELLY → H&T. Copy the ingest URL the dialog shows. It looks like:
$ ingest url
https://api.opensense.murzin.digital/v1/ingest/shelly?token=ds_live_4f3c…&device=hut01
  1. Back in the Shelly web UI, go to Settings → Actions → Report sensor values (called Reporting URL on Gen3). Paste the ingest URL. Set reporting interval to 60 seconds (this is also the default and is fine for HACCP).
  2. Click Save. Click Send test.
ok
OpenSense shows a green dot next to the device and a first reading within 5 s.
warn
Reading appears after 60 s only — the Shelly waited for its next scheduled report. Fine.
alarm
Device stays grey after 2 min. See troubleshooting / device offline.

4 · See the chart

Click the device. The default view is last 24 h with a temperature and a humidity series. The chart is live: new points appear without reload.

For a 5-minute test, breathe near the sensor. Humidity should jump 3–6 % within two reporting cycles. If it does not, the sensor is broken or unpaired; see wrong readings.

5 · Fire a fake alarm

By default a HACCP site has a temperature rule on every device: -2 °C ≤ T ≤ +8 °C with a 15-minute grace period. To verify the alarm path without a real cold-chain event:

  1. Open the device's Rules tab.
  2. Edit the rule: set T ≤ +30 °C (any value below room temperature).
  3. Save. Within one reporting cycle the channel is in ALARM, you get a Telegram message (if connected) and an email.
  4. Restore the rule back to +8 °C. Within two cycles the channel returns to OK. The alarm is logged as an event in the audit trail.

What's next