DRA-TCI-RTI-Srs-Sig-Cond

Supported Applications

The Omega DRA series comprises DIN Rail 2-Wire Temperature Signal Conditioners and Transmitters, specifically the DRA-TCI-2 for thermocouple inputs and the DRA-RTI-2 for RTD inputs. These linearized temperature transmitters convert sensor signals into a proportional 4 to 20 mA process signal suitable for data acquisition systems, PLCs, and distributed control networks.

The series is designed for industrial environments requiring DIN rail mounting (35 mm) within terminal housings or enclosures rated IP20 and IP40 respectively. The DRA-TCI-2 supports thermocouple types J, K, T, E, R, S, and B with eight-segment linearization. The DRA-RTI-2 accepts 2-wire or 3-wire Pt-100 RTDs (alpha = 0.00385).

Operating Conditions & Performance

The series operates within an ambient temperature range of -20 to 70°C (-4 to 158°F) and a storage temperature range of -30 to 85°C (-22 to 185°F). Humidity tolerance is rated at 5 to 95% RH. The devices feature high common mode rejection (CMR), filtering, and low ripple current characteristics.

Performance specifications vary by model:

• DRA-TCI-2 Accuracy: ±0.08% of span for Type K; ±0.1% to ±0.2% for other thermocouple types (typical).
• DRA-RTI-2 Performance: <±0.1% of span accuracy, hysteresis, and repeatability.

The response time is 160 msec (0 to 98%). The excitation voltage for the RTD model is 1 mA. Load resistance capability follows the formula: Rmax (ohms) = (Vsupply - 10) / 0.02.

Measurement Envelopes

The DRA-TCI-2 supports the following input ranges by thermocouple type:

• Type K: 32°F to 2462°F (0°C to 1350°C)
• Type J: 32°F to 1400°F (0°C to 760°C)
• Type T: 32°F to 752°F (0°C to 400°C)
• Type E: 32°F to 1832°F (0°C to 1000°C)
• Types R, S, B: 32°F to 3092°F (0°C to 1700°C)

The DRA-RTI-2 supports an input range of 79°F to 1490°F (26°C to 810°C). Minimum span requirements are documented as 180°F (100°C) for Types K, J, T, and E; and 1170°F (650°C) for Types R, S, and B.

Configuration Options

The series is field rangeable via DIP switches and potentiometers. Test terminals are provided to monitor the output signal without disturbing the process loop. The housing material is polycarbonate with overall dimensions of 3.23" H x 0.9" W x 3.90" D (82 x 22.5 x 99 mm) and a weight of 4.6 oz. (130 g).

Power requirements are satisfied by a supply voltage of 10-40 Vdc. The series is CE certified.

Configuration Options

• DRA-TCI-2: Ordered for specific thermocouple types (J, K, T, E, R, S, B). Cannot be altered after ordering.
• DRA-RTI-2: Configured for 2 or 3-wire Pt-100 RTD inputs.

An optional power supply (DRN-PS-1000) is available, providing 95-240 Vac input and a 24 Vdc @ 1A output.

Key Product Differences

The primary distinction within the series lies in the sensor interface technology:

• DRA-TCI-2 (Thermocouple Input): Designed for thermocouples with eight-segment linearization. Model numbers follow the format DRA-TCI-2-(*) where (*) denotes the specific thermocouple type.
• DRA-RTI-2 (RTD Input): Designed for Pt-100 RTDs, offering tighter performance specifications (<±0.1% of span) compared to typical non-K thermocouple configurations in the TCI series.

The DRA-TCI-2 is ordered specifically for a single thermocouple type and cannot be altered post-manufacture. At the outer limits of range, specific ranges may be obtained using adjacent switch combinations as detailed in the user guide span and zero tables.