Home > Temperature Monitors > Model 18i / 14i / 12i > Specifications
Input Channels
The Model 18i has eight input channels where the Model 14i has four and the Model 12i has two. In every other way, the monitors are identical. Each input may be independently configured for any of the supported sensors. There is no use of scanning or multiplexing.
Sensor Connection: 4-wire differential. DB9 Connectors.
Sensor Types: See Supported Sensor Table.
Sensor Selection: Front Panel or remote interface.
Input Configurations: See input specifications table.
Excitation Modes: Constant-Current or Constant-Voltage.
AC Excitation Frequency: 1.625Hz bipolar square wave.
Voltage Excitations: 10mV. Minimum excitation current is 100nA, maximum is 1.25mA.
Sample Rate:15Hz per channel.
Digital Resolution: 24 bits.
Measurement Accuracy: See input specifications table.
Measurement Drift: 30ppm/oC.
Isolation:Input channels are not isolated.
Measurement Filter: 0.5, 1, 2, 4, 8, 16, 32 and 64 Seconds.
Calibration Curves: Built-in curves for industry standard sensors plus eight user curves with up to 200 entries each. Interpolation is performed using a Cubic Spline.
User Programming
Users may program the instrument via the embedded web server. The IPython Notebook is used to edit, run and debug programs written in the Python language.
Security
Built-in firewall blocks any unused Ethernet service or protocol. Open HTTPS provides an encrypted and secure web server.
User Interface
Display Type: Graphics TFT LCD, 4mm and 8mm character height.
Number of Inputs Displayed: Up to eight.
Keypad: 4-key sealed Silicon Rubber.
Temperature Display: Six significant digits, autoranged.
Display Units: K, C, F or native sensor units.
Display Resolution: Up to seven significant digits.
Web Server
Secure, embedded web server provides: Real-time status and configuration; Firmware updates; User sensor curve upload / download; Live strip charts; Data-logging download.
Data Logging
Data logging is performed to an internal 2GB circular buffer and is time-stamped with a real-time clock. Buffer memory is non-volatile and will retain valid data without AC power. All eight input channel temperatures are recorded.
Status Outputs
Audible and Visual Alarms: Independent audible remote and visual alarms.
Relays: Two dry-contact relays. Both N.C. and N.O. contacts available. Contact ratings are 10.0A.
Remote Interfaces
Maximum reading rate for all interfaces is 10 rdg/s.
Ethernet: Connects to anyEthernet Local Area Network. Electrically isolated. TCP and UDP servers provide remote control by using an ASCII command language. HTTPS provides a built-in web server. SMTP sends e-mail based on alarm conditions.
Modbus: The industrial Open Modbus/TCP protocol is supported on the Ethernet interface.
IEEE-488.2 (GPIB): External Option. Connects via LAN port.
Programming Language: IEEE-488.2 SCPI compatible.
LabVIEW™drivers available for all interfaces.
General
Ambient Temperature: 25°C ± 5°C for specified accuracy.
Mechanical: 5.6”W x 2.9”H x 8.8”D.
Weight: 3.5 Lbs.
AC Power Requirement: IEEE-802.3af Power over Ethernet (requires powered hub or injector) or 5 - 48V AC/DC
AC Power Switch: Front panel.
Conformity: European CE certified.
Calibration: NIST traceable.
Silicon and GaAlAs Diode sensors from Cryo-con or any other manufacturer are directly supported over their full 1.4 to 500K range using built-in calibration curves and sensor data. Plus, non-volatile Flash memory is available for several custom or calibrated sensors.
Platinum RTD sensors can use built-in DIN 43760 (IEC 750) standard setups for 100Ω or 1,000Ω devices. The DIN standard is used for temperatures from 70K to 1020K and extends it down to 30K for cryogenic use. A unique feature of Model 18i / 14i / 12i is the use of an AC ratiometric resistance bridge to cancel low frequency noise.
The Model 18i / 14i / 12i provides robust support for the Negative Temperature Coefficient (NTC) sensors commonly used by cryogenic applications. They include Ruthenium-oxide, Cernox™, Carbon-Glass, Germanium, Carbon-Ceramic and several others. Since they have a negative temperature coefficient, the constant-voltage measurement method will reduce, rather than increase, power dissipation in the sensor as temperature decreases. By maintaining the lowest possible power level, sensor self-heating is minimized and useful temperature range is greatly increased.
An additional advantage to constant-voltage biasing is that NTC resistors lose sensitivity in the upper part of their range. By auto-ranging excitation current to maintain a constant voltage, sensitivity and noise immunity in that range is greatly improved.
Sensor excitation used in conjunction with the constant-voltage feature is a 1.625Hz bipolar square wave. This effectively cancels thermal EMF induced offset errors that sometimes occur in cryogenic systems.
Model 18i / 14i / 12i Supported Sensors | ||
Temperature Range | Example Sensors | |
Diode | 1.4 - 500K | Cryo-con S900 / S950 SI-440, 430, 410 Lakeshore DT-670, 470 |
GaAlAs diode | 1.4K - 500K | Lakeshore TG-120 |
Platinum RTD | 14 - 1200K | Cryo-con CP-100 Cryo-con GP-100 Cryo-con XP-100 Cryo-con XP-1K |
Rhodium-Iron | 1.4 - 800K | Oxford PHZ 0002 |
Germanium Thermistor |
500mK - 400K | AdSem, Inc. |
Carbon Glass | 1.4 - 325K | Lakeshore CGR-1-500 |
CLTS |
4K - 300K |
|
Cernox™ | 500mK - 325K | Lakeshore, all types |
Carbon-Ceramic | 500mK - 300K | TMi-A1 |
Ruthenium Oxide | 500mK - 200K | SI RO-600, SI RO-105 |
Input Specifications | |||
Diode Sensors | PTC Resistor Sensors | NTC Resistor Sensors | |
Input Configuration | Constant-Current DC | Constant-Current AC | Constant-Voltage AC |
Input Range | 0.1V - 2.00V 0.1V - 6.00V |
1.0mA: 0.1 -500Ωm 100µA: 1.0 -5.0KΩ |
Minimum: 5Ω Maximum: 100KΩ |
Accuracy: % Rdg ± % Range |
0.004% ± 80µV | 0.01% + 0.0005% | 14 - 30KΩ: 0.05% + 0.05% 4 - 100KΩ: 0.15% + 0.15% |
Resolution: % Range |
10μV | 0.0003% | 0.0003% |
Excitation | 10μA DC | 1.0mA, 100μA | 10mV 1.25mA to 100nA |
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trademarks of Cryogenic Control Systems, Inc. All other product and company names are trademarks or trade names of their respective companies. |
Tel: (858) 756 3900 Fax: (858) 759 3515
Specifications subject to change without notice. ©Cryogenic Control Systems, Inc. 1998 - 2021 |