OMS 420 - Insitu Oxygen / Combustibles Monitor - MRU Instruments

Description

OMS COMPARISON CHART	OMS COMPACT	OMS RT	OMS HT	OMS EX
ZrO2 sensor for wet O2 analysis	✅	✅	✅	✅
Heated solid electrolyte sensor for combustibles	OPT	OPT	OPT	OPT
DN65 PN6 flange	✅	✅	✅	❌
4″ANSI 150lbs flange	OPT	OPT	OPT	✅
Compact probe with flow guidance (hollow) tube	✅	✅	❌	✅
Ejector tube, needing compressed air	❌	❌	✅	❌
Back-purge for sensors and probe	❌	OPT	✅	OPT
Flue gas temperature	≤1800°F	≤1800°F	≤3000°F	≤1800°F
Transmitter with microprocessor, graphical LCD	✅	✅	✅	✅
IP 65	✅	✅	✅	✅
Integrated auto-calibration	❌	OPT	OPT	OPT
Reference air inlet through natural diffusion, no air pump is required	✅	✅	✅	✅
2x analog 4-20 mA galvanic isolated	✅	✅	✅	✅
Digital RS 485 with Modbus RTU protocol	✅	✅	✅	✅
Hazardous area designation of use: Zone 2 or Class 1, Div 2, Gr A/B/C/D	❌	❌	❌	✅
Special IP 65 pressurized cabinet and z-purge controller, complying to II 3G Ex pz II T3 Gc	❌	❌	❌	✅

Features:

In-situ combustion optimization monitor
Oxygen and Combustibles (COe) Transmitter
combination of O₂ and COe for ideal combustion efficiency
Superior Design for Superior Results!
Real-time measurements
Unique, heated solid electrolyte combustibles sensor
Easy access to sensors for fast and simple service

Benefits:

Make your combustion process more cost-effective.
Get the data to show your organization cares about the environment.

Applications:

Gas Turbines / Compressor Stations / Boiler Manufacturers / Iron & Steel Industry / Power Plants / Refineries / Petrochem

The MRU OMS 420 Series Transmitters are offered in four different versions: Compact, Remote mount, High-temp, or Ex for hazardous locations. The OMS 420’s are the ideal choice to optimize fuel efficiency on combustion sources, with a number of advantages over other transmitters.

The addition of our unique combustibles sensor allows safe operation with a lower Excess Air Ration, translating in to higher efficiencies
The MRU Combustibles Sensor is accurate and stable even down to 1% oxygen – No dilution is needed.
The Flow Guidance Tube design allows the sensor to be mounted near the back of the transmitter to make service fast, easy, and no need for system shutdown.
Mounting versatility
Available Auto Calibration

Better sensors and design for better performance and reliability

Zirconium dioxide O₂ sensor has long life, fast response, high stability & low energy consumption
Heated Solid Electrolyte COe sensor has high accuracy/sensitivity, fast response, long life, and stable down to 1% oxygen -No dilution air required,
Flow Guidance Tube allows easy access to the sensors and are suitable for high dust / particulate or high temperature applications to 3000°F with probe lengths to 6′
Optional Auto Calibration

Measurement component		Measuring range	Resolution	Accuracy
O2	Oxygen	0 … 25 Vol. % absolute	0.01 %	± 0.2 % or ± 5 % of reading*
COe	Combustibles	0 … 1,000 ppm	1 ppm	± 50 ppm or ± 10 % of reading*

General technical data
Warm-up time	min. 30 min.
Flange	DN65 PN6 flange, Ø 6.3” (160 mm)
Probe tube	12” … 6.5-foot (300 … 2,000 mm) Ø 2.36” (60 mm)
Flange temperature	min. 158 ° F … max. 302 °F (+70 … max. +150 °C) (condensation moisture must be avoided)
Response time/T90	< 10 sec.
Analog output	2x current loop 4 … 20 mA, with galvanic isolation linearized for both 0 … 25.00 % O₂ and 0 … 1,000 ppm COe (user definable settings in 0.5 % steps are possible)
Digital output	RS 485 (with Modbus protocol, without galvanic isolation)
Power supply	18 … 24 Vdc (for model OMS 420 compact), 90 … 100 W
Electronics of the transmitter	with local microprocessor, display and 4 push-buttons
Calibration inlet	with test gas fitting for 6/4 mm tube calibration gas supplied manually or automatically via. pneumatic unit PU 420
Back-purge inlet	Only possible with the RT, HT, and EX models! min. 6 … 8 bar compressed air with quick connector for 8 mm tube
Ambient temperature of electronics	-4 … 140 °F (-20 … +60 °C)
Enclosure Transmitter	die cast aluminum, 6.3“ x 6.3“ x 2.36“ (160 x 160 x 60 mm) and 7.87“ (200 mm) probe tube, Ø 1.97“ (50 mm)
Protection class	IP65
Weight	approx. 7.7 lbs. (3.5 kg) (without probe and flange)

Compact / RT & HT	OMS 420_EX	Questionnaire US	Selection Chart EN
Compact / RT & HT	OMS 420_EX	Questionnaire ES	Selection Chart ES