Industrial IoT Wireless RTD Temperature Sensor

01Overview

The NCD Industrial IoT Wireless RTD Temperature Sensor is a battery-powered wireless transmitter that reads a single RTD temperature probe and reports it to an Atrium IIoT Gateway at user-defined intervals over its long-range wireless mesh network. The channel accepts a standard 100 Ω 3-wire PT100 probe (PT1000 selectable) connected via its M12 8-pin connector, and a 15-bit ADC delivers ±0.5°C full-scale accuracy with 0.03125°C nominal resolution. A sample PT100 probe is included for bench testing. The sensor ships configured for the frequency band and power option selected at time of order.

The sensor ships with one of three wireless communication modules. Choose the frequency band that matches your gateway and region — the sensor core, firmware, and Atrium integration are identical across all three. The 900 MHz and 868 MHz options run on NCD’s sub-GHz wireless mesh network, which cuts through industrial noise and interference for secure, long-range communication.

What’s in the Box

• Industrial IoT Wireless RTD Temperature transmitter (main unit) with on-board antenna
• Wireless communication module per your selection (900 MHz, 868 MHz, or 2.4 GHz) with antenna
• One sample 100 Ω 3-wire PT100 probe with PG9 connector (for bench testing only — see note below)
• D-cell (LR20) lithium battery with integrated supercapacitor (power switch ships in the OFF position)
• Mounting hardware

02Specifications

Full technical specifications for the Industrial IoT Wireless RTD Temperature Sensor (SKU PR55-44). The temperature range listed below is for the sensor electronics — the usable measurement range at the probe tip depends on the PT100 probe you fit.

03Prerequisites

Before installing this sensor, make sure you have the following in place.

Hardware Required

• NCD Atrium IIoT Gateway — powered on and connected to your local network
• Industrial IoT Wireless RTD Temperature Sensor (this unit)
• A 100 Ω 3-wire PT100 probe rated for your application (the included sample probe is for bench testing only)
• D-cell (LR20) lithium battery (included, switch in the OFF position for shipping) — or the external-power option if ordered

Software / Network

• A current version of Atrium running on your gateway
• A computer or mobile device on the same local network as the gateway
• A modern web browser (Chrome recommended)
• A gateway configured for the same wireless frequency band as this sensor (900 MHz, 868 MHz, or 2.4 GHz)

04Mounting & Installation

Connect the RTD probe first, then power on and mount the enclosure. The enclosure supports 1/4 NPT, 1/4-28 UNF, and magnet mounting.

Connecting the RTD Probe

The sensor enclosure carries an M12 8-pin connector. A 3-wire PT100 RTD probe is supplied with the sensor, terminated with a PG9 connector that connects to that port — align the connector, push it on, and hand-tighten the coupling until snug so it cannot work loose under vibration. If you are measuring with a PT1000 probe, set the RTD Range accordingly in Hardware Settings (see Section 8).

To wire your own probe, terminate its three leads into the PG9 connector assembly (below) following the M12 pinout — the connector consists of a gland nut, a sealing insert, the body, and a terminal block where the leads are screwed down.

Powering On

1. 1
   Open the enclosure

   Remove the screws securing the enclosure lid and lift the cover to expose the PCB, battery, and power switch.
2. 2
   Set the power switch

   The power switch has three positions: Battery Power, Off, and External Power. It ships in the Off position. Move it to Battery Power for battery operation, or External Power if you ordered the external-power option and have it connected.
3. 3
   Verify power

   Press the CFG button — the on-board TEST LED illuminates to confirm power is present. There is no continuously lit power LED; this is intentional to conserve battery. Press RESET to start the sensor; it sends two data packets on start-up to confirm operation.
4. 4
   Close and seal the enclosure

   Route the probe cable through the enclosure gland, replace the lid, and tighten the screws evenly to maintain the IP65 seal.

Mounting the Enclosure

• Threaded mount: Use the 1/4 NPT or 1/4-28 UNF fitting to mount the enclosure to a compatible boss or bracket.
• Magnet mount: Attach the magnetic mounting plate to any flat ferrous surface — ideal for equipment frames, panels, and pipes.

05Pairing with Atrium

Once powered on, the sensor transmits over its long-range wireless mesh and the gateway begins hearing it. New sensors are held pending (blacklisted) until you whitelist them through the Sensor Details wizard — data is not logged until a sensor is whitelisted. No radio pairing or pre-registration is required.

1. 1
   Power on and close the enclosure

   Set the power switch to Battery Power (or External Power), press RESET, then close the lid. Within one transmission interval (up to 10 minutes at the default 600-second Delay), the gateway will begin receiving its transmissions.
2. 2
   Open Atrium and go to Sensors

   Navigate to your gateway’s local address (e.g. http://ncd-[last-4-of-MAC].local) and click Sensors in the top navigation. A banner shows “X sensors need setup” with detected sensors grouped by type. Your unit appears under the RTD Temperature sensor type.
3. 3
   Open the Sensor Details wizard

   Click the sensor in the banner (or in the Sensors table) to open the Sensor Details wizard. New sensors start pending (blacklisted) — completing the wizard whitelists the sensor so Atrium begins logging its data.
4. 4
   Enter details and save

   Give the sensor a Sensor Name, Asset, and Location (see Section 6). Use Save to whitelist and finish, Save & Next to move to the next pending sensor, or Skip to leave a sensor pending for now.
5. 5
   Confirm it is reporting

   The whitelisted sensor now appears in the Sensors table with a recent Last Heard timestamp. Open its Dashboard to confirm live temperature data.

06Sensor Meta

The Sensor Meta tab controls how Atrium identifies and tracks this sensor. Access it via Sensors → [your sensor] → Configure → Sensor Meta.

07Metric Configuration

The Metrics tab lets you configure conversion formulas, units, custom labels, and dashboard visibility for each data channel. Access it via Configure → Metrics.

This sensor exposes the following metrics:

Custom Conversion Formulas

Each metric supports a custom conversion formula using value as the variable name. Leave the formula as value or blank to display raw data. Examples:

value + 0.5            // Apply a calibration offset to the channel
value * 9/5 + 32       // Convert degrees C to F manually (prefer the global unit setting)
value * 0.01           // Scale a raw integer to a decimal

Custom Labels & Visibility

Each metric can be assigned a Custom Label that replaces the default metric name throughout Atrium (e.g. “Supply Temp”). Unchecking Visible on Dashboard hides that metric’s card and chart without deleting data.

08Hardware Settings

Hardware settings control the sensor’s on-board configuration — transmission interval, RTD probe type, network addressing, and node identity. Changes are staged in Atrium and pushed to the sensor on its next configuration check-in. Access via Configure → Sensor Configuration.

RTD Probe Settings

Network & Timing Settings

Adjusting the Transmission Interval

1. 1
   Go to Sensor Configuration

   Navigate to Sensors → [your sensor] → Configure → Sensor Configuration.
2. 2
   Update the Delay value

   Enter your desired interval in seconds. A minimum of 60 seconds is recommended. Confirm the RTD Range and Wire Type match your fitted probe while you are here.
3. 3
   Click Save Hardware Settings

   The new values are staged and pushed to the sensor on its next configuration check-in.
4. 4
   Update the Report Interval in Sensor Meta

   Update the Report Interval on the Sensor Meta tab to match your new Delay value so offline detection stays accurate.

Battery Life

The sensor delivers up to 5 years of battery life. Actual life depends on your configuration — transmission interval (Delay) is the biggest factor. Longer intervals extend life; frequent transmissions shorten it. To estimate battery life for your exact settings, use NCD’s battery life calculator. For high-frequency monitoring, run the sensor on an external power supply.

09Temperature Units

Atrium provides a global temperature display unit setting that controls how temperature readings appear across the entire interface — all sensors, dashboards, alerts, and reports, including this sensor.

1. 1
   Open Gateway Settings

   Click Settings in the top navigation to open Gateway Configuration.
2. 2
   Select Temperature Display Unit

   Under Temperature Display Unit, toggle between °C and °F. This applies immediately to all temperature readings across Atrium.
3. 3
   Save Configuration

   Click Save Configuration at the bottom of the page to apply the change.

10Sensor Dashboard

The Sensor Dashboard provides a real-time and historical view of all data from this sensor. Access it by clicking the sensor in the Sensors list and selecting Dashboard.

Live Metrics

Time Range & Charts

Use the time range selector to view historical data for the last hour, 6 hours, 24 hours, 7 days, or 30 days. A custom date/time range is also available. Each metric has its own interactive chart — drag to zoom into a time window, double-click to reset. Trend temperature over days or weeks to spot developing process issues.

Mesh Route Map

Click View Map in the Mesh Route Map panel to visualize how this sensor’s data routes through the wireless mesh to reach the gateway. Useful for diagnosing signal path issues in multi-sensor deployments.

Interactive Preview

The panel below simulates the Atrium Sensor Dashboard for this RTD Temperature sensor. Data updates every 5 seconds to demonstrate the live monitoring experience.

11Setting Alerts

Atrium uses a Triggers & Actions model for alerting. A Trigger defines the threshold condition on a metric. An Action defines what happens when all assigned triggers fire. Navigate to Alerts in the top navigation (the page is titled Alerts & Actions) to configure.

Creating a Trigger

1. 1
   Go to Alerts → Triggers

   Click + New Trigger to open the Create Trigger form.
2. 2
   Configure the trigger

   Select the Device, Metric (e.g. temperature), Condition (Above or Below), and Threshold value. The Reset At column sets the value the metric must return to before the trigger can fire again — this hysteresis prevents repeated firing when the value oscillates near the threshold. Click Create Trigger.

Creating an Action

1. 1
   Go to Alerts → Actions

   Click + New Action. Actions link one or more triggers to a response — when all assigned triggers fire simultaneously, the action executes.
2. 2
   Assign triggers and configure the response

   Select the trigger(s) to watch and configure the response. Atrium supports email notifications and relay output actions (to drive an external relay, e.g. to signal or shut down equipment). Email must be configured in Settings → Gateway Configuration for email actions to work.

12Exporting Data

All sensor data can be exported to CSV directly from the Sensor Dashboard for use in spreadsheets, reporting tools, or other analysis software.

1. 1
   Open the Sensor Dashboard

   Navigate to the sensor and click Dashboard.
2. 2
   Select a time range

   Choose the time range you want to export using the selector at the top of the dashboard.
3. 3
   Click “CSV” on the desired metric

   Each metric chart has a CSV download button. Click it to download a timestamped CSV of that metric’s data for the selected time range.

Advanced: SQL Query Export

For bulk exports or custom queries across devices and date ranges, Atrium includes a SQL Query Tool (under Apps) that runs read-only SQL directly against the gateway database and exports the results to CSV. Write a SELECT against the readings table (joined to sensor_meta to filter by sensor name), click Execute Query, then Export CSV. Preset Quick Queries (Recent Readings, Readings by Sensor Name, Total Readings, and more) give you a starting point.

13Product Notes

Reference information for ordering and accessories. See Section 2 for the full hardware specifications.

Buy Now on store.ncd.io →

14Troubleshooting

Common issues and their solutions.

Sensor not appearing in Atrium

• Press the CFG button and confirm the TEST LED lights — if it doesn’t, check the power switch position and the battery or external supply. There is no continuously lit power LED.
• Press RESET; the sensor sends two data packets on start-up to confirm operation.
• Verify the sensor’s Network ID matches the gateway’s Network ID (default 7fff) and that both use the same frequency band. (Note: while in Configuration mode the sensor temporarily uses Network ID 7BCD.)
• Move the sensor to within ~3 feet / 1 meter of the gateway and press RESET to rule out range issues.
• Check that the Atrium gateway is powered on and connected to your network.

Sensor showing as Offline in Atrium

• Verify the Report Interval in Sensor Meta matches the Delay in Sensor Hardware Settings (both default to 600 seconds).
• Check the battery_pct on the last received reading — replace the battery if low.
• Check the RSSI value — remember higher numbers mean a weaker signal. Readings consistently above 75 dBm indicate marginal signal; reposition the sensor or gateway, check the antenna, or add a repeater node.

Temperature reading seems incorrect or shows a fault

• Check the data_valid metric — a fault usually means the RTD probe is disconnected, miswired, or open-circuit. Re-seat the M12 probe connector — make sure it is fully pushed on and the threaded coupling is hand-tight — and check the wiring against the M12 pinout in Section 4.
• Confirm the Set RTD Range (PT100 vs PT1000) and Set RTD Wire Type in Hardware Settings match the probe you fitted.
• Confirm the Temperature Display Unit in Gateway Settings is set to your preferred unit.
• Verify the probe is rated for the temperature being measured; the included sample probe is for room-temperature bench use only.
• Allow 15–30 minutes after installation for the probe to stabilize to ambient conditions.

Hardware settings not updating on sensor

• Settings are staged and applied on the sensor’s next configuration check-in — wait one full transmission interval (up to 10 minutes at the default 600-second Delay) after saving.
• To apply changes immediately, power-cycle the sensor with the RESET button, which opens a configuration window on boot.
• Confirm the sensor is actively transmitting by checking the Last Heard timestamp on the dashboard.
• Ensure only one gateway is attempting over-the-air configuration of this sensor at a time.

15Factory Reset

A factory reset restores the sensor’s wireless module to default settings. This is useful if the sensor is not being detected by a gateway, or if you are redeploying it to a new network. Reset behavior is governed by how long the CFG control is held after a RESET.

Option A — Magnetic Switches (no disassembly)

1. 1
   Trigger the RESET switch

   Hold a magnet near the RESET magnetic switch, then move it away.
2. 2
   Wait 1 second

   Allow approximately 1 second before proceeding.
3. 3
   Hold the CFG switch for ~20 seconds

   Hold the magnet near the CFG magnetic switch for approximately 20 seconds, then move it away. The hold must exceed 15 seconds to trigger a factory reset — a shorter hold only enters Configuration Mode.
4. 4
   Wait 3–5 seconds

   Allow 3–5 seconds for the reset to complete.
5. 5
   Trigger the RESET switch again

   Hold the magnet near the RESET switch once more, then move it away. This returns the sensor to normal Run Mode.

Option B — Physical Buttons (requires opening enclosure)

1. 1
   Open the enclosure

   Remove the screws and lift the lid to expose the PCB.
2. 2
   Press and release the RESET button

   Press and release the RESET button on the PCB.
3. 3
   Wait 1 second, then hold CFG for ~20 seconds

   Wait approximately 1 second, then press and hold the CFG button for approximately 20 seconds. The hold must exceed 15 seconds to trigger a factory reset. Release the button when done.
4. 4
   Wait 3–5 seconds

   Allow 3–5 seconds for the reset to complete.
5. 5
   Press RESET, then close the enclosure

   Press and release the RESET button to return the sensor to normal Run Mode. Replace the lid and re-secure the screws.