Model 3020P​

Explosion Proof Percent Oxygen Analyzer​​​


The Model 3020P is a versatile microprocessor-based instrument for detecting oxygen at the percent (%) level in a variety of gases. This instrument serves as the explosion-proof, bulkhead-mount version of the 3000P, and is designed to make the task of percent oxygen analysis easier, faster and more precise than ever before. Simple menu choices, externally accessible switches and dual LCD and LED displays make setup and operation clear and quick.

Analysis Ranges

Three user-configurable ranges are standard, with an excellent linearity precluding the need to recalibrate when changing ranges. Two fully programmable concentration alarms satisfy nearly any requirement. All features offer a sophistication that assures years of service.


Two standard 0-1 VDC and two 4-20 mADC isolated outputs provide both concentration and range identification. A bi-directional RS-232 serial interface is incorporated to relay information to a host computer for remote monitoring of critical functions.


All controls and displays are available from outside the housing. The instrument has two simple operator controls. A digital meter, an alphanumeric display, and a sample flow meter give the operator constant feedback.

Additional Advantages

  • Linearity of analysis across three user-selectable ranges

  • Auto-ranging capabilities

  • Digital Interface allows monitoring from a remote station

  • Extended-life, maintenance-free sensor

  • Comprehensive self testing function


  • C      Integrally mounted cal/zero valves

  • M     Isolated 4-20 mADC signal and range ID output

  • V      Plumbed for vacuum service

  • F      Flame arrestors for Class 1, Div 1, Group C/D service

  • G     Flame arrestors for Class 1, Div 1, Group C/D service with cal valves

  • H     Flame arrestors for Group B (hydrogen) service

  • I       Flame arrestors for hydrogen service with cal valves

  • S      Stainless steel cell block​


  • An explosion proof NEMA 4/7 rated enclosure

  • 2-line alphanumeric display screen, driven by microprocessor electronics continuously prompting and informing the operator

  • High resolution, accurate readings of oxygen content from low ppm levels through​ 100%

  • Advanced Micro-Fuel Cell designed for trace analysis, with a one year warranty and an expected life of two years

  • Versatile analysis over a wide range of applications

  • Microprocessor based electronics: 8-bit CMOS microprocessor with 32 kB RAM and 128 kB ROM

  • Three user-definable output ranges (from 0-1% through 0-100%) assuring a perfect match for the user's process

  • Air-calibration range for convenient spanning at 20.9%

  • Auto-ranging automatically selects the proper preset range for a given measurement. Manual override allows the user to lock onto a specific range of interest

  • Two adjustable concentration alarms and a system failure alarm

  • Extensive self-diagnostic testing at start-up and on demand with continuous power-supply monitoring

  • Two way RS-232 serial digital port for use with a computer or other digital communication device

  • Four analog outputs; two for measurement (0-1 VDC and isolated 4-20 mADC) and two for range identification

  • NEC and ATEX rated configurations



​3 customer programmable ranges (minimum 0-1%) with auto-ranging
(if option with flame arrestors is requested, maximum range is 25% O2)
Calibration Range: 0-25%


​± 2% of FS at a constant temperature
± 5% of FS over operating temperature range (once temperature equilibrium has been reached)


​0.5% of FS

​Response Time

​(B-1) 90% of FS at 77°F (25°C) in less than 10 seconds


​32° to 122°F (0° to 50°C)


​Signal:         Analytical measurement 0-1 VDC
Range ID:    0-1 VDC


​Analysis:       5 digit red LED, 3/5" high numerals
Menu:           20 character, 2 line LCD
Data Lines:  Bi-directional RS-232C serial interface, baud rate 2400 (remote monitoring of
                       all critical functions)


​One system failure alarm contact to detect power failure
Two fully programmable concentration alarm set points and corresponding Form C 3 amp contacts


​115 to 230 VAC, 50/60 Hz


​Teledyne Micro-Fuel Cell, Class B-1
Optional: A3, A5, B-3, C-3


​Explosion proof enclosure is U/L and CSA listed for Class 1, Div 1, Group B, C & D service NEMA 4/7 rated

(for NEC version)

​25.63"H x 15.25"W x 11"D
(65.10 x 38.74 x 27.94 cm)


  • Monitoring inert gas blanketing

  • Air separation and liquefaction

  • Chemical reaction monitoring

  • Semiconductor manufacturing

  • Petrochemical process control

  • Quality assurance

  • Gas analysis certification