DRA-RTT-2 DIN Rail Loop Powered RTD Input Signal Conditioner
DIN Rail Mount Loop-Powered RTD Input Signal Conditioner
Supported Applications
The Omega DRA-RTT-2 is a non-isolated signal conditioner designed for temperature measurement and signal transmission. It accepts a 3-wire Pt 100 RTD input (a = 0.00385, according to DIN 43760/BS1904) and converts this into a linearly proportional 4 to 20 mA process current output.
Field ranging is accomplished using an internal DIP switch array for coarse range setting and front panel accessible multi-turn zero and span potentiometers for fine tuning. Test terminals are provided to monitor the transmitter's 4 to 20 mA output without disturbing the actual process loop.
Operating Conditions & Performance
The DRA-RTT-2 operates within an ambient temperature range of -20 to 70°C (-4 to 158°F) with a humidity rating of 5 to 95% RH. The device is housed in polycarbonate providing IP40 protection, while the terminal housing offers IP20 protection.
Performance specifications include an accuracy of ±0.1% of span (including linearity, hysteresis and repeatability) and temperature stability of < ±0.015% of span/°C. The sensor excitation is maintained at < 1 mA to minimize self-heating effects.
Input configuration supports the following ranges:
• Zero Range (Tmin): -55 to 202°C (-67 to 395°F)
• Span Range (Tspan): 30 to 810°C (86 to 1490°F)
The device requires a loop power supply of 10 to 36 Vdc. Supply variation effect is < ±0.03% of span for full change.
Configuration Options
The DRA-RTT-2 series supports specific configuration options and accessories:
• Mounting: 35 mm DIN rail mounting is standard, with overall dimensions of 90 H x 17.5 W x 58 mm D (3.54 x 0.7 x 2.28").
• Ranging Configuration: Three "zero" DIP switches and three "span" DIP switches allow for coarse selection of the input range, supplemented by two fine-tuning potentiometers.
• Power Supply Option: The iDRN-PS-1000 power supply is available (95 to 240 Vac input, 24 Vdc @ 1 A output).
• Warranty: OMEGACARE™ Extended Warranty Program options are offered.
The unit weighs 70 g (2.5 oz). Storage temperature range is -30 to 85°C (-22 to 185°F).
Key Product Differences
The DRA-RTT-2 model number identifies the non-isolated RTD input signal conditioner configuration. The series does not include isolated variants in this specific data sheet scope.
| Electrical Output | 4 to 20 mA |
| Enclosure Ratings | IP20, IP40 |
| Excitation Current | < 1 mA |
| Height | 90 mm |
| Isolation | None |
| Lead Compensation Error | < ±0.03% of span for full change |
| Length | 58 mm |
| Loop Resistance | Rmax (Ω) = (Vsupply - 10)/0.02 |
| Materials | Polycarbonate |
| Mounting | DIN Rail 35 mm Standard |
| Operating Temperature, Max | 70 °C |
| Operating Temperature, Min | -20 °C |
| Relative Humidity | 5 to 95% RH, noncondensing |
| Resistance Tolerance | < ±0.05°C/10 Ω lead resistance |
| Series ID | DRA-RTT-2-Sig-Cond |
| Storage Temperature, Max | 85 °C |
| Storage Temperature, Min | -30 °C |
| Supply Power Type | DC |
| Temperature Stability | <±0.015% of span/°C |
| Weight | 70 g |
| Width | 17.5 mm |
| Zero Setting Adjustable Range | -55 to 202°C |