Description
The TKMD is a resistance thermometer with connection head B in the version with GL type approval, manufacturer type Müller WT-MR1G.
It is designed for fixed plant installation at measuring points where type approval is required: The manufacturer's data sheet shows the GL mark with the number TAA00002H5. The aluminum connection head accommodates a ceramic base with connection posts, the process connection at the head is M24x1.5, the cable entry is M20x1.5, and the protection class is IP 54. The protection tube made of 1.4571 (316Ti) or 1.4401 (316) withstands up to 600 °C, the process pressure is max. PN16.
Compared to the TKMC, this is not the same product with an additional mark: This version is limited to a length of 200 mm instead of 2000 mm and has a different sheath material and accessory kit. The source does not list a transmitter as an accessory here, but it does include connection cables up to 6 m, compression fittings, and sheet metal flanges. Screw-in (ES) and immersion (ET) designs are available, as well as protection tube diameters of 3 to 15 mm; the selection is limited for the sheathed element and in the immersion design.
The measuring element is a Pt100 or Pt1000, single or double, in a 2-, 3- or 4-wire circuit, as a standard element or as a sheathed element. The sensor's operating range is -200 ... +450 °C, and the accuracy ranges in five steps from Class A to B1/10DIN. The resistance is at the ceramic base in the head, the test voltage is 500 VDC, and the response time on the 3×0.4 mm tube is t90 5 s.
Before ordering, please note: The approval is documented by a mark and number, not by a certificate – the manufacturer's data sheet does not name a certifying body, and the certificate is not available. The language versions contradict each other regarding the sheath material: The English page names 2.4816 (Inconel 600), while the German page and the order codes in both languages name 1.4401 (316) – 1.4401 applies here. A response time is missing for the other tube geometries. The ambient temperature is not the medium temperature: The head is limited to 480 °C, the element ends at 450 °C. IP 54 only applies to the connection head; the source does not specify a standard for the accuracy classes, and terminal assignment, CE mark, and explosion protection are missing. Both carry the product identification KD, distinguished only by the first digit: 4 ... 7 for the TKMD, 0 ... 3 for the TKMC (WT-MR1) – the latter up to 2000 mm long and sheathed with 2.4816.
Advantages at a glance
- GL type approval TAA00002H5, documented by mark and number
- Pt100 or Pt1000, 2-, 3- or 4-wire circuit
- Operating range -200 ... +450 °C, Class A to B1/10DIN
- Process pressure max. PN16, installation lengths 50 to 200 mm
- Protection tube 1.4571 or 1.4401, Ø 3 to 15 mm, up to 600 °C
- Connection head B made of aluminum, IP 54, cable entry M20x1.5
- Version without GL available as TKMC up to 2000 mm length