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Continuous Process Analyzer for Binary Gas Mixtures by Thermal Conductivity - 425 Series
Item # Model 425RMN7
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Item # Model 425RMN7, Continuous Process Analyzer for Binary Gas Mixtures by Thermal Conductivity, ex-proof sensor housing with rack mount control cabinet (two separate enclosures)
The Nova 425 Thermal conductivity (TC) Analyzer has many applications in industry where the measurement of one gas in a two gas or some multi-gas mixtures is required. The Nova TC cell is temperature controlled and its high stability enables it to be used even in high purity measurements. Since the TC cell does not consume the sample, have any moving parts, hot wires, or sealed chemicals, it will last for many years.
In operation, the TC cell detects the rate at which the sample gas conducts heat away from a Resistance Temperature Device (RTD) with reference to a similar RTD surrounded by air (or other reference gas). A sample gas containing the gas to be measured will cause the temperature, and its resistance, to change with respect to the reference RTD. This will cause an output from the Wheatstone bridge measuring circuit which is calibrated and displayed on a digital meter.
: Wall Mounted NEMA7 UL/CSA Explosion-proof sensor cabinet with 19" rack mount control cabinet (two separate cabinets)
Method of Detection
, air, or CO
, air, Ar, O
, He, etc
in Ar, CO
, He, H
RTD-based TC cell can be used to measure almost any binary gas mixture such as H
, air, SO
, Ar, He, NH
0-2% to 0-100% and suppressed ranges such as 95-100%
0.1% of gas to be measured
Accuracy & Repeatability
±1% of full scale
Less than 1% of full scale per month
Response Time (T-90)
10-15 seconds to 90% step change
Ambient Temperature Range
32 to 122°F (0 to 50°C), Lower temperatures (-5°F, -20°C) with Cold Weather Package
±1% of full scale
Size & Weight
Dimensions will vary depending on enclosure style and options required
115 VAC, 60 Hz
220 VAC, 50 Hz
4-20 mA into 500 ohms non-isolated standard
Isolated 4-20 mA, RS232, RS485, MODBUS, Ethernet outputs
High and/or low alarm contacts available, relay contacts SPDT 5A @ 220 VAC rating
Low flow alarm
Binary Gas Analyzer
Hazardous Area Rating Options
Class 1, Div 1, Grp A-D Hazardous Area Rating
For continuous analysis of many binary gas mixtures comprised of H
, Ar, He, NH
, air, and others. Applications include heat treating atmospheres, welding gas mixtures, blanketing gas mixtures, ammonia synthesis, leak detection, purge monitoring, flue gas, magnesium blanketing by SF
Bright digital readout
Lower cost than infrared, GC or mass spectrometer
High stability, microprocessor-controlled, long-life thermal conductivity (TC) cell
Easy-to-maintain modular layout
Built in sample pump or pressure regulator
4-20 mA outputs
Sensors mounted in temperature controlled heated box to improve accuracy
Hi/Low gas, low flow, and diagnostic alarms available
Isolated analog, RS232, RS485, MODBUS, and Ethernet outputs available
Sample conditioning systems available for removal of moisture, acidic gas, and dust
Cabinet purge system available for use in hazardous areas
One-step 'cal-now' button calibration with touch screen LCD display
Full automatic calibration with touch screen LCD display
Cold weather package for operation to -5°F (-20°C)
Cabinet coolers can be fitted to most models
Air or nitrogen for zero
Analyzed calibration gas for span
All Nova analyzers are built using proven technologies and techniques. If this product does not suit your application, please contact Nova. In many cases, we are able to build an analyzer specific to your needs.
425 Process TC Analyzer
Nova Analytical Systems is a part of the