118 230 Series Temperature Transmitters Instruments Features Sensor input fully isolated from power supply potential 230 Series Temperature Transmitters/Monitors 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 PTC RTD Model 231, 231P, and 234 Model 234 Features Operates from 100 mK to 420 K with appropriate NTC RTD The 230 Series Temperature Transmitters include three models: Model 231, Model 231P, and Model 234. Each model supports a different sensor type. Includes serial interface Model 234D Features Operates from 100 mK to 420 K with appropriate NTC RTD Model 234D Includes serial interface 6-digit LED display www.lakeshore.com Lake Shore Cryotronics, Inc. (614) 891-2244 fax: (614) 818-1600 e-mail: [email protected]

230 Series Temperature Transmitters 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...

120 230 Series Temperature Transmitters Instruments 231 Thermometry 231P 234/234D Number of inputs 1 1 1 Measurement type 4-lead differential 4-lead differential 4-lead differential Sensor type Silicon diode, GaAlAs diode Platinum Carbon-glass, germanium, Cernox™ Sensor temperature coefficient Negative Positive Negative Sensor units Volts (V) Ohms (Ω) Ohms (Ω) Input range 0 V to 5 V 0 Ω to 312 Ω 1 Ω to 300 kΩ Sensor excitation 10 µA ±0.1% DC current 500 µA ±0.02% DC current Constant voltage pinned at 5 mV or 10 mV dependent on resistance range Update rate 5 readings per s 5 readings per s 4 readings...

230 Series Temperature Transmitters 231 Output Instruments 231P 121 234/234D Number of outputs 1 Output type Current source, isolated from power source – output or sensor can be grounded, but not both (all models) Output range 4 mA to 20 mA or 0 mA to 20 mA (for 0 V to 10 V with provided 500 Ω 0.02%, 25 ppm resistor) (all models) Output compliance 10 V (500 Ω max load) 10 V (500 Ω max load) 10 V (500 Ω max load) Output temperature ranges Range 1 Range 2 Range 3 Range 4 Range 5 Range 6 0 K to 20 K 0 K to 100 K 0 K to 200 K 0 K to 325 K 0 K to 475 K 0 K to 1000 K 0 K to 20 K 0 K to 100 K 0 K to...

122 230 Series Temperature Transmitters Instruments 231 231P 234/234D 0 mA to 20 mA output (0 V to 10 V with 500 Ω, 0.02% load resistor) Output resolution Voltage Temperature equivalence Range 1 Range 2 Range 3 Range 4 Range 5 Range 6 0.6 mV 0.6 mV 0.61 mV 1.2 mK 6.1 mK 12.2 mK 19.8 mK 29 mK 61 mK Not used 6.1 mK 12.2 mK 19.8 mK 29 mK 61 mK 0.6 mK 1.2 mK 6.1 mK 12.2 mK 18.3 mK 15.2 mK Output accuracy Voltage 3 mV (0.03% of full scale) 3 mV (0.03% of full scale) ±4.5 mV (±0.025% of full scale ±0.02% resistor accuracy) Temperature equivalence Range 1 Range 2 Range 3 Range 4 Range 5 Range 6 6 mK...

230 Series Temperature Transmitters Instruments 123 Ordering Information 2001 Part number 231 231-115 234D-230 Description Transmitter card for use with Silicon Diode 231 transmitter with a 115 VAC (50/60 Hz) wall plug-in power supply 231 transmitter with 230 VAC wall plug-in power supply Transmitter for use with Platinum Resistor 231P transmitter with 115 VAC (50/60 Hz) wall plug-in power supply 231P transmitter with 230 VAC wall plug-in power supply Transmitter for use with Carbon-Glass, Germanium, and Cernox™ 234 transmitter with 115 VAC (50/60 Hz) wall plug-in power supply 234 transmitter...