|
Model 231, 231P, and 234 |
|
 |
The 230 Series Temperature Transmitters include three models: Model 231, Model 231P, and Model 234. Each model supports a different sensor type. |
|
Model 234 |
|
|
| |
| |
| Features |
| |
- Sensor input fully isolated from power supply potential
- Different models support various sensor types
- 4-lead differential measurement
- Output range of 4 mA to 20 mA or 0 mA to 20 mA (0 V to 10 V)
- Available rack-mount case holds up to 12 units
|
| |
| Model 231 Features |
| |
- Operates from 1.4 K to 500 K with appropriate diode
|
| |
| Model 231P Features |
| |
- Operates from 1.4 K to 800 K with appropriate NTC RTD
|
| |
| Model 234 Features |
| |
- Operates from 100 mK to 420 K with appropriate NTC RTD
- Includes serial interface
|
| |
| Model 234D Features |
| |
- Operates from 100 mK to 420 K with appropriate NTC RTD
- Includes serial interface
- 6-digit LED display
|
| ....................................................................................................... |
| You may also be interested in... |
|
|
|
|
|
|
|
 |
|
| Description |
| |
| Model 231 |
| |
| The Model 231 operates with either silicon diode or gallium-aluminum-arsenide (GaAlAs) diode sensors. |
| |
| Excited with a 10 µA current source from the Model 231, the sensors produce a voltage that depends on temperature. A microcontroller reads the voltage through an A/D converter and translates it into temperature using a temperature response curve. The Model 231 includes two standard curves for DT-470 and DT-670 diode sensors. It also supports a single CalCurve™ option for calibrated sensors (TG-120 diodes require a CalCurve™). |
| |
| Model 231P |
| |
| The Model 231P uses a PT-100 Series platinum sensor. The Model 231P excites the sensor with a 500 µA current to produce a measurable signal. Either the standard platinum curve (IEC 751) or a CalCurve™ is used for temperature conversion. |
| |
| Model 234 |
| |
| The Model 234 operates with Cernox™, carbon-glass, germanium, or other negative temperature coefficient (NTC) resistance temperature sensors. The Model 234 excites the sensor with a constant voltage of 10 mV or less to minimize the effects of sensor self-heating at low temperatures. |
| |
| The Model 234 employs an analog control circuit to maintain a constant voltage signal across the sensor. A series of reference resistors convert the resulting sensor current to a voltage. A microcontroller reads the voltage with an A/D converter, calculates sensor resistance, and converts the resistance to temperature by table interpolation (requires a CalCurve™ for temperature conversion). The sensor excitation voltage is reversed each reading to compensate for thermal voltages and offsets. |
| |
| Click here for more information |
|
|
