Thunder Scientific

2500/2500ST Benchtop/Mobile Humidity Generator

Self contained system capable of producing atmospheres of known humidities using NIST proven, two-pressure principle, 0.5 %RH uncertainty

Call Today!
800-567-8686 Normally ships in 6-8 Weeks

  Request Quote

Can We Help You?

CALL US   EMAIL US   CHAT LIVE

Our product experts are here to help you find the right solution for your application!

The Model 2500 Benchtop 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 formula:
 

%RH= fs/ fc · es/ ec · Pc/ Ps · 100


To generate a known humidity, the computer controls the pressure ratio Pc /Ps utilizing the enhancement factor ratio fs/fc and the effective degree of saturation es/ec. 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.

Principle of Operation

The Model 2500 Benchtop 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 left most 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/min, l/h, cfm and cfh. Humidity is calculated and displayed in percent relative humidity (%RH). The asterisk in the left most 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

Coefficients for each transducer are calculated by the computer and stored in the system’s nonvolatile memory until the next calibration is performed.

 

• 0.5 %RH Uncertainty
• Traceable to SI
• Self Contained and Mobile
• Automated Control of User Setpoints
• 2500 ControLog® Automation Software
• HumiCalc® with Uncertainty Software
• Computerized Internal Transducer Calibration
• Low Noise Air Compressor with Air Dryer
• RS-232C Serial Interface

Relative Humidity Range 10 to 95 %RH
Relative Humidity Uncertainty 0.5 %RH
Chamber Temperature Range 0 to 70 C
Chamber Temperature Range 10 to 70 C
Chamber Temperature Uniformity 0.1 C
Chamber Temperature Uncertainty 0.06 C
Chamber Pressure Uncertainty 0.15% FS
Chamber Pressure Range Ambient
Display Resolution 0.01
Gas Flow Rate Range 5 to 20 L/min
Gas Flow Rate Resolution 0.02 L/min
Gas Flow Rate Uncertainty 2% FS
Gas Type Air or Nitrogen
Gas Pressure Rating (MAWP) 175 psiG
Heating Stainless Steel Immersion Heater
Heating/Cooling Rate 2.5 Minutes Per C Average
Cooling 1/3 hp R-134A Refrigeration System
Chamber Window 6" x 6" (152 mm x 152 mm)
Physical Dimensions:
Model 2500 H Dim:19" (483 mm)
W Dim:33" (838 mm)
D Dim:20" (508 mm)
Model 2500ST H Dim:22" (559 mm)
W Dim:36" (914 mm)
D Dim:23" (584 mm)
Physical Dimensions of Cart:
Model 2500 H Dim:33.25" (845 mm)
W Dim:40" (1.20 m)
D Dim:23" (584 mm)
Model 2500ST H Dim:33.25" (845 mm)
W Dim:43" (1.09 m)
D Dim:26" (660 mm)
Physical Dimensions 2500 with Cart:
Model 2500 H Dim:53" (1.35 m)
W Dim:40" (1.20 m)
D Dim:23" (584 mm)
Model 2500ST H Dim:56" (1.42 m)
W Dim:43" (1.09 m)
D Dim:26" (660 mm)
Chamber Dimensions:
Model 2500 H Dim:12" (305 mm)
W Dim:12" (305 mm)
D Dim:10" (254 mm)
Model 2500ST H Dim:15" (381 mm)
W Dim:15" (381 mm)
D Dim:12" (305 mm)
Access Port:
Standard Port Diameter:1.9" (48 mm
Location:Right Side
TPA Port Diameter:1.9" (48 mm
Location:Right Side
LPD Port Diameter:1.93" (49 mm)
Location:In Door
MPD Port Diameter:1.125" (28.5 mm)
Location:In Door
Utilities
Electrical Power 100/120 V~, 15 A, 50/60 Hz
Electrical Power (Optional) 200/240 V~, 8 A, 50/60 Hz
Electrical Power For ST Model 200/240 V~, 8 A, 60 Hz
Electrical Power For ST Model (Optional) 200/240 V~, 8 A, 50 Hz
Air Compressor 100/115 V~, 10 A, 50/60 Hz
Air Compressor (Optional) 220/240 V~, 6.3 A, 50/60 Hz
Air Supply (External) Clean Oil Free Instrument Air @ 175 psiG & 20 L/min
Environmental
Operating Temperature 15 to 30 C
Storage Temperature 0 to 50 C
Humidity 5 to 95% Non-condensing

The fluid jacketed test chamber can accommodate humidity sensors, hygrothermographs, chilled mirror hygrometers, and various material samples for environmental testing. Virtually any humidity and temperature point may be generated, for any length of time, within the operational limits of the generator. The output of the device under test may then be compared with the generator's printed data for analysis.

Humidity Sensors And Chart Recorders: Insert humidity probes through the two inch port in the side of the chamber or place hygrothermographs into the chamber and you can: determine humidity calibration accuracy and characterize humidity sensitivity by subjecting the sensing system to a variety of humidity levels; perform operational checks such as the sensing systems capability to correctly calculate and display other humidity parameters; determine the repeatability, stability, hysteresis, and drift characteristics of various humidity sensing systems.

Chilled Mirror Hygrometers: Install the actual chilled mirror head into the chamber or insert a sample tube through the test port and draw a sample through the chilled mirror head and you can: verify mirror temperature measurement accuracy (calibration) when the hygrometer is in thermal equilibrium with its environment; perform operational checks of the heat pump and optical components before and after mirror cleaning and balancing; determine whether the hygrometer is controlling the mirror deposit in the liquid phase or ice phase when operating at dew and frost points below 0 °C; determine if the hygrometer is correctly calculating other humidity parameters; determine the hygrometer's repeatability, stability, and drift characteristics.

Environmental Testing: The 2500 can serve as a test bed for evaluation and R&D of humidity sensors, humidity sensing systems, and humidity sensitive products, e.g., polymers, composites, film, magnetic medium, blood gas analysis, pharmaceuticals, soil hydrology, consumables, electronics, optics, etc. Depending on the temperature and humidity being generated, the 2500 may operate continuously from hours to months. With continuous generation of a nominal 50 %RH at 21 °C, the reservoir will last about two weeks between refills.

Item
Description
Availability
Price
Accessories
Has 2 access ports with a diameter of 1.9" (48 mm) in the right side of the chamber and 1 additional hygrometer sample port with a 1/4" (6.35 mm) fitting
Normally ships in 6-8 Weeks
Call Today!
800-567-8686
Expanded chamber temperature range of 10 C to +70 C
Normally ships in 6-8 Weeks
Call Today!
800-567-8686
Designed for the user to add a flush mounted panel to the chamber opening, each corner has 10mm mounting threads to attach your panel
Normally ships in 6-8 Weeks
Call Today!
800-567-8686
Provides external temperature probe access through the top panel for measurement of the saturation temperature
Normally ships in 6-8 Weeks
Call Today!
800-567-8686
Doors
Has 6 each 1.125" (28.5 mm) diameter access ports through the door for multi probe calibration
Normally ships in 6-8 Weeks
Call Today!
800-567-8686
Provides the system with improved chamber temperature uniformity
Normally ships in 6-8 Weeks
Call Today!
800-567-8686
Software
Windows based ControLog fully automates the operation of a Thunder Scientific 2500 Humidity Generator and allows various device connections through a number of different interfaces
Normally ships in 6-8 Weeks
Call Today!
800-567-8686
ST Model Only
Provides a gas flow rate of 10 to 40 Liters per minute; however this option is only available with the 2500ST model
In Stock
Call Today!
800-567-8686
4 each 1.125" (28.5 mm) diameter access ports with a window configuration (ST Models Only)
In Stock
Call Today!
800-567-8686
Improves chamber temperature uniformity for high volume sensor calibrations
Normally ships in 6-8 Weeks
Call Today!
800-567-8686
Transport
Provides the lab a way to move the Model 2500 to remote sensor locations and calibrate them in the field, as long as you have power and an air hook-up available
In Stock
Call Today!
800-567-8686