MTL5074 TEMPERATURE CONVERTER

THC or RTD input

The MTL5074 converts a low-level dc signal from a temperature sensor mounted in a hazardous area into a 4/20mA current for driving a safe-area load. Software selectable features include linearisation, ranging, monitoring, testing and tagging for eight thermocouple types and 2-, 3- or 4-wire RTDs. For thermocouples requiring coldjunction compensation, the HAZ-CJC plug can be ordered with the product, and includes an integral CJC sensor

Number of channels One Signal source Types J, K, T, E, R, S, B or N THCs to BS 4937 EMF input 2/3/4-wire platinum RTDs to BS 1904/DIN43760 (100Ω at 0°C) Location of signal source Zone 0, IIC, T4 hazardous area Div.1, Group A, hazardous location Input signal range –75 to +75mV, or 0 to 400Ω (Input impedance 10MΩ) Input signal span 3 to 150mV, or 10 to 400Ω RTD excitation current 200µA nominal Cold junction compensation Automatic or selectable Cold junction compensation error ≤1.0°C Common mode rejection 120dB for 240V at 50Hz or 60Hz Series mode rejection 40dB for 50Hz or 60Hz Calibration accuracy (at 20°C) (includes hysteresis, non-linearity and repeatability) Inputs: mV/THC: ±15µV or ±0.05% of input value (whichever is greater) RTD: ±80mΩ Output: ±11µA Temperature drift (typical) Inputs: mV/THC: ±0.003% of input value/°C RTD: ±7mΩ/°C Output: ±0.6µA/°C Example of calibration accuracy and temperature drift (RTD input) Span: 250Ω Accuracy: ± (0.08/250 + 11/16000) x 100% =0.1% of span Temperature drift: ± (0.007/250 x 16000 + 0.6) µA/°C = ±1.0µA/°C Safety drive on sensor burnout Upscale, downscale, or off Output range 4 to 20mA nominal (direct or reverse) Maximum load resistance 600Ω LED indicator Green: one provided for power and status indication Power requirement, Vs with 20mA signal 68mA at 24V 82mA at 20V 52mA at 35V Power dissipation within unit with 20mA signal 1.5W at 24V 1.6W at 35V

MTL5074

Includes HAZ-CJC signal plug (with internal CJC sensor). For use with thermocouple, mV or RTD inputs

MTL5074-RTD

Includes standard HAZ1-3 signal plug. For use with mV or RTD inputs. (Can be used with thermocouples with cold-junction compensation if HAZ-CJC plug is fitted.)

HAZ-CJC

Hazardous-area signal plug for terminals 1 to 3 including cold-junction compensation sensor.