Description
The TEMD is a screw-in temperature sensor in an intrinsically safe design.
It is the Ex version of the series and is designed for installation in potentially explosive areas with gases. It is screwed directly into pipes, tanks, or units; the protective tube is made of stainless steel 1.4571, the system pressure is PN 25, and the protection class is at least IP 65. Compared to the other screw-in sensors in the series, it goes significantly higher in the medium: up to +425 °C.
It has no display, buttons, or limit contacts; the measured value is sent as a current or voltage signal for evaluation, and settings are made with the DEV-KMA configurator and TrComm software.
Measurements are taken with a Pt100 in a 2-wire circuit in Class A, B, or AA in the range of -50 … +425 °C with a minimum span of 50 °C. The output offers a choice between 4 … 20 mA in 2-wire technology and voltage signals such as 0 … 10 V in 3-wire technology. The accuracy is max. 0.1 % of the measuring range plus sensor error at 24-bit resolution, powered by 12 … 30 VDC.
Please note before ordering: The data sheet specifies installation for gases in Zone 0, Zone 1, and Zone 2 and lists three markings: II 1 G Ex ia IIC T6..T1 Ga, II 1/2 G Ex ia IIC T6..T1 Ga/Gb, and II 2 G Ex ia IIC T6..T1 Gb; it does not explicitly state which marking is assigned to which zone. The certifications are TÜV 21 ATEX 201293 X according to directive 2014/34/EU and IECEx TUN 21.0005X. Both approval numbers end in X, which means special conditions apply; these are found in the operating instructions and not in the data sheet. The temperature class is given as T6..T1, not as a single value; according to the data sheet, the applicable class depends on the installation. The ambient temperature depends on the output type: -20 … +75 °C is permissible for the 2-wire current output, but only -20 … +50 °C for the 3-wire voltage output – anyone who orders the voltage output and designs for the upper value will be 25 K too high. And the ambient temperature is not the medium temperature: The medium can be up to +425 °C, but the electronics in the head cannot – above +85 °C, they can be destroyed. A CE mark is not documented in the data sheet, and a declaration of conformity is not available. The version without explosion protection, with display and two limit contacts, is the TEMB.
Advantages at a Glance
- Intrinsically safe, marking II 1 G Ex ia IIC T6..T1 Ga
- ATEX TÜV 21 ATEX 201293 X and IECEx TUN 21.0005X
- Installation for gases in Zone 0, Zone 1, and Zone 2
- Pt100 in 2-wire circuit, medium -50 … +425 °C
- Accuracy max. 0.1 % of measuring range, 24-bit resolution
- 4 … 20 mA in 2-wire or 0 … 10 V in 3-wire technology