‧相對濕度範圍: 10 ~ 98%,  解析度 0.02%,  準確性 ±0.5%.
‧NIST 標準認可為基礎之雙壓力操作原理, NIST 可追溯數據.
‧全自動控制使用者所設定的測試值. 自動操作軟體 ControLogTM.
‧全電腦化自動轉換校正功能. RS-232C 系列式介面.
‧實驗箱內尺寸:
 Model 2500  H19" x W33" x D20"
 Model 2500-S  H19" x W36" x D23"
 Model 2500-ST H22" x W36" x D23"

Thunder Scientific Model 2500 Humidity Generator

‧Accuracy ± 0.5 % RH
‧Traceable to NIST
‧Based on NIST Proven Two-Pressure Principle
‧Self Contained and Mobile
‧Automated Control of User Setpoints
‧Shipped with ControLog(TM) Automation Software and Humicalc(R) Humidity Conversion Software
‧Computerized Internal Transducer Calbration
‧Automatically Applies Enhancement Factors
‧RS-232C Serial Interface

The Model 2500 Humidity Generator is a self contained system capable of producing atmospheres of known humidities using the fundamental, NIST proven, "two-pressure" principle. This system is capable of continuously supplying accurately known humidity values for instrument calibration, evaluation, and verification, as well as for environmental testing.

Simply apply power and the 2500 will power-up ready to generate. Humidity setpoint values are input by the operator from the front panel keypad and are limited only by the range of the 2500 humidity generator.

Relative humidities are calculated from the measurements of pressure and temperature with the following formula:

Formula: %RH = f_s/f_c x e_s/e_c x P_c/P_s x 100

To generate a known humidity, the computer controls the pressure ratio P_c/P_s utilizing the enhancement factor ratio f_s/f_c and the effective degree of saturation e_s/e_c. Humidity produced is solely dependent on the measurement of pressures and temperatures and does not rely on any other device (such as a dew point hygrometer, psychrometer, or humidity sensor) for the measurement of water vapor content. Precision humidity generation is determined by the accuracy of the pressure measurements and on the accuracy and uniformity of temperature throughout the generating system.

General Information
The Model 2500 Humidity Generator operates using an on board multifunction CPU in conjunction with other peripheral cards to perform calculation and control functions. The embedded computer control system allows the 2500 to generate known humidity levels unattended, freeing the operating technician from the task of system monitoring and adjustment. A computer and/or printer may be connected via the bi-directional RS-232C interface ports allowing remote setpoint control and continuous acquisition of system data.

Humidity and temperature setpoint values are input by the operator from the front panel keypad while visual indications of system status are displayed in real time on the liquid crystal display.

Control / Display Screen
All Control and measurement parameters critical to the operation of the humidity generator are displayed on this screen. Each parameter in the leftmost column is identified with a brief title and corresponding units. The generator operates in a variety of user selectable pressure, temperature, and flow units. Some of these are °C, °F, psi, "Hg, Tor, mbar, kPa, l/m, l/h, cfm and cfh. Humidity is calculated and displayed in percent relative humidity (%RH). The asterisk in the leftmost column indicates the active humidity control parameter. The "SetPnt" column lists control setpoints and the "Actual" column lists all of the measured data and calculated parameters of the generator.

Temperature Control: The system utilizes a fluid jacketed test chamber for extremely stable temperature control. Temperature setpoint control is attained by controlling the temperature of the circulating fluid medium that jackets the test chamber and associated humidity generation components. Chamber and saturation temperatures are governed by this medium and are digitally controlled by the computer at any value between 0 °C and 70 °C using PID (proportional-integral-derivative) algorithms.

Pressure and Flow Control: Pressure control and mass flow control are accomplished through computer actuation of electromechanical valve assemblies. Pressure and flow are measured continuously and controlled using PID algorithms similar to those employed in temperature control.

Calibration: The 2500 humidity generator employs an integral programmatic calibration scheme allowing the temperature and pressure transducers to be calibrated while they are electrically connected to the humidity generator.

Calibration / Display Screen
Coefficients for each transducer are calculated by the computer and stored in the systems nonvolatile memory until the next calibration is performed.

Specifications

Relative Humidity Range: 10% to 98%
Relative Humidity Resolution: 0.02%
Relative Humidity Accuracy: ±0.5% @ PcTc(k=2)
Chamber Temperature Range: 0°C to 70°C
Chamber Temperature Range: (Optional) -10°C to +70°C
Chamber Temperature Resolution: 0.02°C
Chamber Temperature Uniformity:** ±0.1°C
Chamber Temperature Accuracy: ±0.06°C
Chamber Pressure Range: Ambient
Gas Flow Rate Range: 2 to 20 slpm
Gas Type: Air or Nitrogen
Gas Pressure Rating (MAWP): 175 psiG
Heating/Cooling Rate: 2.5 Minutes Per °C Average
Chamber Window: 6" x 6" (152 mm x 152 mm) Window in Door
　 　
Physical Dimensions: 　
2500 19" (483 mm) H
33" (838 mm) W
20" ( 508 mm) D 
2500S 19" (483 mm) H
36" (914 mm) W
20" (508 mm) D 
2500ST 22" (559 mm) H
36" (914 mm) W
23" (584 mm) D 
Physical Dimensions of Cart: 　
2500 33.25" 9845 mm) H
40" (1.20 m) W
23" (584 mm) D 
2500S 33.25" (845 mm) H
43" (1.09 m) W
23" (584 mm) D 
2500ST  33.25" (845 mm) H
43" (1.09 m) W
26" (660 mm) D
　 　
Physical Dimensions 2500 With Cart: 　
2500 53" (1.35 m) H
40" (1.20 m) W
23" (584 mm) D 
2500S 53" (1.35 m) H
43" (1.09 m) W
23" (584 mm) D
2500ST 56" (1.42 m)
43" (1.04 m) W
26" (660 mm) D 
　 　
Chamber Dimensions: 　
2500 12" (305 mm) H
12" (305 mm) W
10" (254 mm) D 
2500S 12" (305 mm) H
15" (381 mm) W
10" (254 mm) D 
2500ST 15" (381 mm) H
15" (381 mm) W
12" (305 mm) D
　 　
Utilities: 　
Electrical Power: 100/120 V~, 15 A, 50/60 Hz
(Optional) 200/240 V~, 8 A, 50/60 Hz
Air Compressor: 100/120 V~, 5 A, 50/60 Hz
(Optional) 200/240 V~, 2.5 A, 50/60 Hz
Air Supply (External): Clean, Oil Free Instrument Air
@ 175 psiG & 20 slpm
　 　
Environmental: 　
Operating Temperature: 15°C to 30°C
Storage Temperature: 0°C to 50°C
Humidity: 5 to 95% Non-condensing