Web-Thermometer NTC

Reliable Temperature Monitoring with the Web Thermometer NTC from Wiesemann & Theis

The Web Thermometer NTC from Wiesemann & Theis is a compact, network-enabled temperature measuring device with an integrated NTC sensor covering the range from -45 °C to +75 °C. 

It is ideally suited for continuous monitoring of server rooms, network cabinets, offices, and all applications that require precise room or ambient temperature control within the standard climate range. 

The device features a powerful data logger (up to 20 years of storage capacity), an intuitive web interface, and supports modern Industry 4.0 protocols such as MQTT, REST, and OPC UA. Thanks to Power-over-Ethernet (PoE), high noise immunity, and optional DAkkS calibration, it is the ideal solution for professional IT and building monitoring. 

With a 5-year warranty and numerous alarm and integration options, the Web Thermometer NTC sets new standards for reliability and flexibility.

Technical Highlights at a Glance

• Integrated NTC sensor: -45 °C … +75 °C
• Integrated data logger: min. 16 weeks to max. 20 years
• PoE (Class 1) or external power supply 12–48 V DC
• Support for MQTT, REST, OPC UA, Modbus-TCP, SNMP v3
• Up to 12 individual alarms via e-mail, SNMP trap, Syslog, MQTT, etc.
• Dynamic integration of current measurements via AJAX/JavaScript
• Optional ISO factory calibration or DAkkS calibration with certificate
• High noise immunity according to EN 61000-6-2
• 5-year manufacturer’s warranty

Precise NTC Sensor for the Climate Range

The Web Thermometer NTC is equipped with a high-quality, permanently integrated NTC sensor, specifically optimized for the typical temperature range of -45 °C to +75 °C. 

This range covers all standard requirements for room and ambient temperature monitoring — from slightly cooled server rooms to warm production areas or office environments. Measurements are recorded continuously and made immediately available via the integrated web interface or network protocol.

Powerful Data Logger and Cloud Integration

The internal data logger stores temperature values depending on the adjustable sampling rate (15 s to 60 min) for periods between 16 weeks and 20 years. The battery-backed real-time clock ensures correct time stamps even during power outages, synchronized via NTP. 

Alternatively, measurement data can be automatically uploaded via FTP, sent as e-mail attachments, or transferred directly to the W&T Cloud – ensuring worldwide access to historical temperature data at any time.

Modern Industry 4.0 Interfaces

The Web Thermometer NTC is fully prepared for Industry 4.0 and IoT integration:

• MQTT – direct connection to cloud and IoT platforms
• REST API – easy integration into custom web applications
• OPC UA – standard automation protocol
• Modbus-TCP – integration with PLC and SCADA systems
• SNMP v1/v2c/v3 – seamless integration into existing monitoring systems
• Syslog, TCP/UDP sockets, FTP, Sensobase (ODBC)
• Current temperature readings can be dynamically embedded into custom websites or dashboards using JavaScript (AJAX).

Flexible Alarming and Green IT

Up to 12 individual alarms can be freely configured (threshold, hysteresis, delay). When a limit value is exceeded, the device automatically sends:

• E-mails (also as periodic reports)
• SNMP traps
• Syslog messages
• MQTT publish notifications
• TCP/UDP alerts

Especially in data centers, the Web Thermometer NTC supports optimization of air conditioning, thereby actively helping to reduce energy consumption – a key contribution to Green IT.

Easy Installation and Reliable Power Supply

The device is preferably powered via Power-over-Ethernet (PoE Class 1, max. 3.84 W) – ideal for installation in ceilings or cabinets without separate power lines. 

Alternatively, an external 12–48 V DC power supply can be connected via plug-in screw terminals. The RJ45 network interface is galvanically isolated and supports 10/100 MBit/s with Auto-MDIX.

Standards, Calibration and Warranty

The Web Thermometer NTC meets the highest quality requirements:

• High interference immunity according to EN 61000-6-2
• Low emissions according to EN 55032:2015 + A1 Class B
• Optional ISO factory calibration or DAkkS calibration with certificate
• 5-year manufacturer’s warranty

Typical Applications

• Server room and rack monitoring
• Network cabinets and IT infrastructure
• Offices, conference rooms, and call centers
• Warehouses and production facilities
• Building technology and energy management
• Museums, archives, and climate-controlled rooms
• Green IT projects for optimizing room climate control

The Web Thermometer NTC from Wiesemann & Theis is the perfect solution for anyone who needs reliable and convenient room and ambient temperature monitoring within the range of -45 °C to +75 °C. 

Whether used as a stand-alone device with e-mail alert, as an IoT sensor with MQTT, or as part of complex monitoring systems via OPC UA – it impresses with intuitive operation, high flexibility, and long-term quality. 

With optional DAkkS calibration, PoE power supply, and a 5-year warranty, it is the first choice for IT managers, facility managers, and system integrators.