Frequently asked questions

If your question is not here, email grande.chuvash@gmail.com and we will add it.

General

Is this for me?

OpenSense fits small operators (1–10 sensors per site) who need any of: HACCP cold-chain logs, Legionella temperature compliance, server-room monitoring, indoor climate monitoring (CO₂ / RH), or energy load monitoring. EU-based, EU pricing, EU data residency.

If you have >50 sensors per site or a regulated GxP environment, see Eupry / Testo comparison.

Do I have to buy your hardware?

No. We do not sell hardware. You buy a Shelly, an Aqara, an Efento or a DIY ESP32 from any source. We integrate.

How many sensors per site?

The Solo tier caps at 20 devices per site. Above that, contact us — pricing stays linear but we ask to understand the use case.

Does it work outside the EU?

It works technically — the ingest URL is reachable from anywhere — but the product is priced and localised for EU operators. Hardware recommendations and regulatory references are EU-centric. We are not trying to compete in the US market.

Hardware

Which sensor should I buy?

Default: Shelly H&T Gen3. €30, WiFi, the easiest pairing. See hardware for alternatives.

Will it work with my Govee / SwitchBot / Inkbird?

If the sensor can POST JSON to a URL, yes (use the generic ingest). If it only talks to its own cloud, we do not have an integration today. The most common "Bluetooth only" sensors fall into this bucket; they need a phone-side relay we do not maintain.

What about wired probes (PT100, thermocouples)?

Route them through a DIY ESP32 with a MAX31865 / MAX31855 amplifier. See DIY ESP32 for a starting point; the wiring is left as an exercise.

Can a single device have multiple probes?

Yes. Up to 32 measurements per ingest request. See POST /v1/ingest, label field.

Compliance

Does this satisfy an EU food inspector?

For HACCP, yes — see verticals/haccp. We have operators who have passed Slovak ŠVPS inspections with the PDF report as the temperature log. Different member states have different inspectors; some prefer paper logs alongside.

Is this enough for Legionella?

For the temperature monitoring part, yes — see verticals/legionella. The annual lab swab is still required by local water authorities; OpenSense reduces the frequency of that, it does not eliminate it.

Does this satisfy GxP / GMP?

No. We are not pharma-grade. Use Eupry or Testo if you have a GxP obligation.

GDPR DPA?

Yes. See security/compliance. Clicking "I accept" on signup is acceptance under EU law; we sign hard-copy DPAs on request.

Pricing

How much does it cost?

€29 per month per site, single tier today. Additional sites on the same account are €19 per month each. See pricing.

Is there a free trial?

14 days, full Solo tier, no card.

What payment methods?

Card or SEPA via Stripe. Monthly billing default; annual is a 10% discount on request.

What happens if I cancel?

Account is paused for 30 days (read-only dashboard, devices stop emitting). After 30 days, irreversible deletion. Re-activate any time in the first 30 days, full state restored.

Data and privacy

Where is my data?

eu-central — Hetzner Falkenstein, Germany. See security/architecture.

Can I export my data?

Yes. The dashboard's Account → Export everything produces a ZIP with all raw measurements, alerts, reports and notes. CSV + JSON.

Can I delete my data?

Yes, one-click. Irreversible after 30 days.

Do you use my data to train AI models?

No. No, no.

Operations

What is the cadence?

You choose. Default is 60 s for WiFi sensors, 15 min for LoRaWAN. See the hardware page for each device type.

How long is data retained?

13 months raw, 5 years of 5 min / 1 h rollups, forever for daily rollups and alert events. See security/architecture.

Can I run reports retroactively?

Yes, for any period covered by raw retention (13 months) or rollup retention (5 years for 5 min / 1 h granularity).

Do you have a status page?

https://opensense.murzin.digital/status. One-second-resolution health check on the ingest service.

Is there a community / forum?

Not yet. Drop a note on the GitHub issues if you'd like one.

Integrations

Telegram alerts?

Yes, free, every tier. See Account → Integrations → Telegram.

Slack / MS Teams alerts?

Webhook-only today. Native Slack/Teams apps are on the roadmap.

Home Assistant?

Pull side: yes — Z2M → OpenSense bridge as in Aqara TH. Push side (HA reads from OpenSense): a read-only token + the measurements API.

Grafana?

Bring-your-own. Read via the measurements API into a Postgres datasource via a Python sync, or use the JSON datasource plugin to call our API directly.

MQTT publish for downstream consumers?

Not in Solo. Team-tier feature on the roadmap.