Description
The TNMA is an immersion thermometer in the form of a handheld lance with HART, manufacturer type Müller MKTS-EL.
It is designed for mobile use – hay, compost, hot asphalt: The lance is inserted into the material until the tip is deep enough. It is available in lengths from 500 to 2000 mm and upon request, with Ø 10 mm made of stainless steel 1.4571. The weight is approximately 845 g (1000 mm with display), the protection class is IP 65 for the electronics and IP 68 for the sensor.
The process connection is explicitly listed in the data sheet as a handheld lance, no installation: There are no threads or sealing surfaces. Readings are taken directly from the handle – the 7-segment LCD has a resolution of 0.1 °C, its accuracy is ±1% or 1°C, whichever is greater, and it runs on a CR 2032 battery.
At the input, there is a Pt100 in 3-wire circuit in classes A, B, and AA, or alternatively a Type K thermocouple. The maximum range extends from -50 ... +400 °C with a smallest span of 50 K. The output is either the resistance directly on the connector or 4 ... 20 mA with HART in the 2-wire loop; the total accuracy via HART is 0.3% of the range at 16 bit. The transmitter is supplied from the current loop with 10 ... 35 VDC.
Please note before ordering: The sensor ranges up to +400 °C, but the factory setting of the transmitter only goes up to +200 °C; if you want to measure higher, you must specify the configuration as custom. The ambient temperature is not the medium temperature: With the transmitter, -20 ... +80 °C is permissible, without the transmitter -30 ... +100 °C, the medium may have -50 ... +400 °C. Supply and burden formula do not match: 10 ... 35 VDC are specified, but the burden formula calculates with UB - 12 V and results in a negative value below 12 V; sister sheets consistently state 12 ... 40 VDC. The source provides no information on the lifespan of the CR 2032 battery or battery regulations. A statement "system pressure 25 bar" is on the sheet, but has no discernible meaning for a handheld lance without a process connection – suitability for process pressure is therefore not proven. Super Seal and Deutsch DT04 three-pole only lead one sensor. Configuration is done using the HART interface with USB and software (01310-00220). A CE mark, a declaration of conformity, and explosion protection are not documented in the data sheet.
Advantages at a Glance
- Handheld lance Ø 10 mm in 500 to 2000 mm length – no installation required
- Pt100 in 3-wire circuit or Type K thermocouple
- Medium -50 ... +400 °C, accuracy 0.3% of range at 16 bit
- 4 ... 20 mA with HART or resistance directly on the connector
- Display on handle with 0.1 °C resolution, CR 2032 battery
- Lance made of stainless steel 1.4571, IP 65 / IP 68