RTD temperature sensor can directly provide accurate input signal of temperature changes for display instruments, recording instruments, signal conditioners, scanister and computer.
Specification:
1. RTD temperature range and accuracy chart
Type of sensing element | Measuring range | Allowable deviation Δt |
Pt100 | -200~420℃ | Class B (-200~800℃) Permissible deviation ±(0.30+0.005|t|) |
Class A (-200~650℃) Permissible deviation ±(0.15+0.002|t|) |
Cu50 | -100~150℃ | -50~100℃ Permissible deviation ±(0.30+6.0*10-3t) |
Note: t is the actual measuring temperature absolute value of the temperature sensing element.
2. Transmitter parameter chart
Input | Platinum thermistor: PT100, PT1000 |
Output | 4-20mA |
Intrinsic error | ±0.2%, ±0.5% |
Transmission mode | Two wire |
Supply voltage | DC 12~35V, rated voltage DC 24V |
Load resistance | 0~600Ω (DC 24V), rated load 250Ω |
Temperature influence | ≤0.05/1℃ |
Working environment | Temperature: -25~+80℃, humidity: 5%~95%, mechanical vibration: f≤55Hz, amplitude<0.15mm |
Display | 3 1/2digital display or LCD display, temperature unit is degree centigrade (℃). |
3. Meter and protection head type (unit: mm)

4. Selection chart
Type of sensing element | Meter type | Installing form | Mode of connection | Thermowell diameter | Thermowell total length |
T4: Pt100; T6: Pt1000 | P0: No meter; P2: Meter with digital display (unit: ℃); P4: Intelligent meter with digital display (unit: ℃) | I1: No fixed device; I2: Fixed card sets of thread joint (thread M27*2mm); I3: Movable card sets of thread joint (thread M27*2mm); I4: Fixed card sets of flange (flang DN 15mm); I6: Taper thermowell and fixing thread (thread M27*2mm) | C3: Standard waterproof protection head; C4: Explosion-proof protection head | D0: Φ16mm (when thermowell insertion depth≥300mm); D1: Φ12mm (when thermowell insertion depth<300mm) | 225~2150mm |
Note: The sensing element is sheath RTD sensor, thermowell material is stainless steel, and circuit adopts non-isolated type. When ordering products, write the thermowell insertion depth l and the corresponding temperature range for output 4~20mA signal you need.
Tips: Troubleshooting of Pt100 RTD sensor
- Fault: Instrument shows negative value.
Possible cause: Wrong connection between display instrument and Pt100 RTD sensor, or short circuit of Pt100 RTD sensor.
Processing method: Correct the connection, find out short circuit position and strengthen insulation. - Fault: Instrument shows that the indicated value of Pt100 RTD sensor is lower than the actual value or the indicating value is unstable.
Possible cause: There are metal chips, dust, dirt among wiring terminal and Pt100 RTD sensor short circuit.
Processing method: Remove metal chips, clean dust and water drops, find out short circuit position and strengthen insulation. - Fault: Instrument displays infinity.
Possible reasons: Pt100 RTD sensor or lead wire short circuit, or connection terminal loosening, etc.
Processing method: Change the resistance body, or welding and tighten the thread screw. - Fault: Relation between Pt100 RTD sensor resistance value and temperature has changed.
Possible cause: Resistance wire of Pt100 RTD sensor become corrosive and degenerative.
Processing method: Replace resistance wire of Pt100 RTD sensor.
RTD sensor with digital meter can directly display high-precision real-time temperature. It converts temperature to 4-20mA standard signal proportional to the electrical signals of thermistor, and outputs to display instrument or DCS system in control room. Built-in small transmitter adopts silicone rubber seal structure, good anti-interference ability, shock and humidity, apply to harsh environments. Measuring temperature range -200~+420 ℃.