{"product_id":"tmmb-oberflaechen-temperatursensor-auf-haftmagnet","title":"TMMB surface temperature sensor on magnet","description":"\u003cp\u003eThe \u003cstrong\u003eTMMB\u003c\/strong\u003e is a surface temperature sensor on a holding magnet, manufacturer type Müller \u003cstrong\u003eMETS-WTM\u003c\/strong\u003e.\u003c\/p\u003e\n\u003cp\u003eIt is placed on a pipe or a vessel and holds itself – no drilling, no process connection, no intervention in the medium. The spring-loaded measuring face presses against the surface, the magnet pulls with \u003cstrong\u003e66 N\u003c\/strong\u003e.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eThis device has no display and no keys\u003c\/strong\u003e – it is set exclusively over HART. Otherwise it is identical to the \u003cstrong\u003eTMMA\u003c\/strong\u003e (METS-WSM), which carries the display. Anyone who wants to read the value on site orders the TMMA.\u003c\/p\u003e\n\u003cp\u003eThe input is a \u003cstrong\u003ePt100 in 4-wire connection\u003c\/strong\u003e in classes A, B and AA (B 1\/3 DIN), with a range of \u003cstrong\u003e-50 … +200 °C\u003c\/strong\u003e at a smallest span of 50 K; up to -50 … +250 °C on request. The output is \u003cstrong\u003e4 … 20 mA with HART\u003c\/strong\u003e in the 2-wire loop, current range 3.8 … 20.5 mA, with 3.6 mA on short circuit and 21 mA on break. Accuracy is \u003cstrong\u003e0.3 % of the range\u003c\/strong\u003e at \u003cstrong\u003e16 bit\u003c\/strong\u003e, the response time 20 ms, the measuring rate 10 measurements per second, the filter 0 … 99 s.\u003c\/p\u003e\n\u003cp\u003eThe \u003cstrong\u003etwo limit contacts\u003c\/strong\u003e are PNP or NPN with 30 VDC \/ 200 mA, optionally 1000 mA; switching point and hysteresis are adjustable across the whole measuring range, the switching delay from 0.0 to 999.9 s, and failsafe behavior as well. Supply comes from the HART current loop with \u003cstrong\u003e12 … 40 VDC\u003c\/strong\u003e, load R = (UB − 12 V) \/ 21 mA, with reverse polarity protection.\u003c\/p\u003e\n\u003cp\u003eMechanically: holding magnet in \u003cstrong\u003eAlnico 500\u003c\/strong\u003e, measuring face Ø 6 mm spring-loaded with 1.5 mm travel, sensor body stainless steel \u003cstrong\u003e1.4571\u003c\/strong\u003e, PBT GF30 housing, connection either at the side or on top, weight approx. 259 g, system pressure PN 25, protection at least \u003cstrong\u003eIP 65\u003c\/strong\u003e at the electronics.\u003c\/p\u003e\n\u003cp\u003eThree points the manufacturer leaves open and that belong in the planning. \u003cstrong\u003eThe sensor sits with the magnet directly on the hot surface.\u003c\/strong\u003e The measuring face may reach +200 °C, the electronics in the head only +80 °C – how much heat travels into the head is not documented, and above +85 °C the electronics can be destroyed. The \u003cstrong\u003egalvanic isolation applies only between the switching outputs and the amplifier\u003c\/strong\u003e, not against the loop and not against the surface the magnet sits on. And how the \u003cstrong\u003eholding force changes with temperature\u003c\/strong\u003e the source does not say.\u003c\/p\u003e\n\u003cp\u003eTen electrical connections are available – which one carries how many limit contacts is not a free choice: two contacts are only possible on M12 five- and eight-pin, on MIL and on the cable version; on Deutsch DT04 four-pin and on Super Seal, none. Configuration uses the \u003cstrong\u003eHART interface with USB and software\u003c\/strong\u003e, order number 01310-00220; when communicating through a HART modem a resistance of 250 Ω has to be taken into account. No CE marking is documented and no declaration of conformity is available.\u003c\/p\u003e\n\u003ch3\u003eAdvantages at a glance\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eMeasuring without intervening in the process – holding magnet with 66 N\u003c\/li\u003e\n\u003cli\u003eSpring-loaded measuring face Ø 6 mm, 1.5 mm travel\u003c\/li\u003e\n\u003cli\u003ePt100 4-wire, classes A, B and AA\u003c\/li\u003e\n\u003cli\u003eMedium -50 to +200 °C, up to +250 °C on request\u003c\/li\u003e\n\u003cli\u003e4 … 20 mA with HART, accuracy 0.3 % of the range\u003c\/li\u003e\n\u003cli\u003eTwo limit contacts with adjustable delay\u003c\/li\u003e\n\u003cli\u003eSensor body stainless steel 1.4571, magnet Alnico 500\u003c\/li\u003e\n\u003cli\u003eProtection at least IP 65\u003c\/li\u003e\n\u003cli\u003eVersion with display available as TMMA\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"octogon Shop","offers":[{"title":"Default Title","offer_id":57245618766150,"sku":null,"price":0.0,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0819\/5558\/6374\/files\/TMMB_METS-WTM_titelbild_762e2e44-6288-4034-aa0b-09e27d501197.webp?v=1788951932","url":"https:\/\/octogon-sensors.com\/en\/products\/tmmb-surface-temperature-sensor-on-magnet","provider":"octogon GmbH","version":"1.0","type":"link"}