opensense
opensense

Efento NS-T

LoRaWAN T/RH for thick walls and 10-year battery life

The Efento NS-T (and the multi-channel NX-T variants) is a LoRaWAN battery sensor designed for industrial cold-chain. The NS-T-3 model is the temperature-only variant; NS-T-3-RH adds humidity. We treat all of them as "a LoRaWAN device that reports through TTN".

Use Efento when:

  • The site has thick walls and WiFi does not reach the fridge.
  • The site is large (hotel, hospital, warehouse) and rolling out a WiFi rolled out a WiFi infrastructure is not in scope.
  • Battery service intervals must be measured in years, not months.

Buy

  • ≈ €85–€110 per probe. Buy direct from Efento or through Conrad / Distrelec.
  • Picks a region: EU868 for Europe. Do not buy US915 even if it is cheaper on eBay — it is illegal to operate in the EU and the gateway will not hear it.

Gateway

You need a LoRaWAN gateway that can reach The Things Network (TTN).

  • For a single site, a Mikrotik wAP LR8 kit (€180) is sufficient and is on the TTN supported list.
  • For a building, an outdoor gateway (RAK7268C) gives you up to 5 km line-of-sight.
  • Inside a city, a public TTN gateway may already cover you. Check the TTN coverage map before buying a gateway.

Provision in TTN

  1. In TTN Console (eu1.cloud.thethings.network), create an Application called opensense-<sitename>.
  2. + Add end device → Manual → Efento NS-T-3. The Efento profile is in the LoRaWAN device repository.
  3. Read the DevEUI, AppEUI and AppKey off the QR sticker on the sensor. Enter them.
  4. Select frequency plan EU868 and LoRaWAN version 1.0.3.
  5. The device joins on next power-cycle (push the magnet against the sensor for 3 s).

Provision in OpenSense

  1. In OpenSense, + ADD DEVICE → LORAWAN → TTN. Copy the webhook URL.
  2. In TTN Console, Application → Integrations → Webhooks → + Add webhook.
  3. Webhook format: JSON.
  4. Base URL: paste the OpenSense webhook URL (includes auth token).
  5. Enable Uplink message only. Leave the other event types off.
  6. Save.

Within one transmission cycle the readings appear in OpenSense.

Payload decoder

Efento sends a compact binary payload. TTN runs Efento's official decoder (included in the device profile). The decoded JSON OpenSense receives:

{
  "measurements": [
    { "type": "temperature", "value": 4.13 },
    { "type": "humidity",    "value": 67.8 }
  ],
  "battery": 95
}

OpenSense maps measurements[].type to sensor kinds. If you flash a custom decoder, ensure your output has the same shape, or write your own generic LoRaWAN mapping.

Cadence

  • Default: 15 minutes.
  • HACCP: change to 5 minutes in the Efento NFC mobile app.
  • Battery-conserving: 30 minutes (still fine for slow-changing climates).

LoRaWAN airtime regulation in EU868 caps your duty cycle at 1 % on most channels — at 5-minute cadence you are well under that limit for a single device. At more than ~50 devices per gateway, sit down and do the airtime math before raising cadence further.

Mount

  • The plastic enclosure is sealed (IP67) and rated for −30 °C to +60 °C.
  • For freezers below −30 °C, use the NS-T-3X variant or an external probe. The standard PCB battery dies fast at very low temperatures.
  • For Legionella supply probes, use the NS-T-3 with the external contact probe accessory. Mount on the riser, not on the loop return, unless you also have a return probe.

What you give up

  • LoRaWAN is one-way for our purposes — we receive, we do not push back. You cannot remotely change cadence from OpenSense; you have to walk to the sensor with the NFC phone app.
  • Latency: a "down" sensor is detected by absence-of-uplink, so the alarm fires 2 × cadence minutes after the actual fault. For a 15-min cadence this is 30 min — acceptable for cold chain, marginal for legionella.