Description
The TRMA is a room temperature sensor.
It is built for air-conditioning and cold storage – refrigeration plants on ships, cold rooms, building services. The housing is screwed to the wall through two Ø 4.6 mm holes 45.5 mm apart; the short protective tube of 30 mm and Ø 6 mm reaches into the room. The housing is made of PBT GF30 in black with flammability rating UL94 HB, measures approx. 117 × 28 × 32 mm and weighs 50 g; any mounting position.
Two versions are available: the sensing element sits either directly on the connector – the sensor then outputs its resistance directly – or behind a HART transmitter that turns it into 4 … 20 mA. Setting is done in software over HART: LRL, URL, LRV, URV, filter, adjustment and simulation.
The input takes one or two Pt100 or Pt1000 in 2-, 3- or 4-wire connection, in classes A, B and AA; with an amplifier, one Pt100 is provided for. The measuring range runs without an amplifier from -30 to +90 °C, with an amplifier from -30 to +80 °C at a smallest span of 50 K – the same difference applies to the working temperature of the device. The current output delivers 4 … 20 mA with HART in the 2-wire loop, overall range 3.6 … 21 mA with 21 mA on break, short circuit or underrange. Total error is 0.3 % of the range at 16 bit resolution, the measuring rate 10 measurements per second, the filter 0 … 99 s. The sensor is supplied from the HART current loop with 12 … 40 VDC, with reverse polarity protection.
Note before ordering: The protective tube is fixed at 30 mm and Ø 6 mm – whether other lengths are possible can be clarified on request. Protection is at least IP 65 but depends on the chosen connection; the assignment is available on request. Ten connections are available, from M12×1 to a cable outlet – two sensors do not work with every connector. Configuration uses the HART interface with USB and software; when communicating through a HART modem, a minimum resistance of 250 Ω must be taken into account. UL94 HB is the lowest grade in the series. A declaration of conformity is available on request.
Benefits at a glance
- Room sensor for cold rooms, air-conditioning and building services
- Pt100 or Pt1000, classes A, B and AA
- Two versions: resistance direct or 4 … 20 mA with HART
- Range -30 to +90 °C without, -30 to +80 °C with amplifier
- Total error 0.3 % of the range, 16 bit
- PBT GF30 housing, only 50 g, wall mounting 45.5 mm
- Protective tube 30 mm Ø 6 mm, protection at least IP 65