HART protocol temperature transmitter

The TMT162 temperature measurement transmitter comes standard with a high-intensity backlit LCD for ease of reading under all operating and environmental conditions. The 4-20 mA, 2 wire loop powered device also includes HART functionality offering faster commissioning long with online set-up and reconfiguring facilities.

Designed for installation across a range of applications, the TMT162 is a dual channel device offering a digital measurement accuracy of 0.1 K for Pt100 sensors from -50 to +200°C. Built-in surge protection protects it from overvoltage surge damage.

Explosion-proof, Ex d, and intrinsically safe, Ex ia, the device will accept two-sensor inputs for 2 x Pt100 3 wire or Pt100 4 wire and TC connection capabilities. All internationally accepted approvals are available and EMC is to NAMUR NE21 standards.

Primary temperature measurement capability is provided by independent two-sensor inputs and include a facility for over- and under-range results. Sensor input channels can also be mathematically combined for differential and average value measurements. The unit's measurement software will also identify a faulty sensor as well as any increase in terminal resistance, such as corrosion of sensor terminals or supply cabling, according to the European chemical industry standards NAMUR NE43.

As a back-up to the primary measurement system, the transmitter features drift warning and drift alarm capabilities. Maximum allowable drift parameters can be pre-set by the user to suit site conditions. Automatic switching from sensor 1 to sensor 2, on failure, can be enabled.

In drift warning mode, any violation of the pre-sets activates a warning using the HART protocol and also displays an 'attention' symbol on the display. A breach in drift alarm mode activates an alarm using the 4-20 mA signal as well as an error code on the display panel, according to NAMUR NE89.

The specially-designed large-character display panel also includes bargraph output facilities and is designed to be easily read from greater than average distances, day or night.