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MODEL 221R Oxygen Deficiency Monitors

Updated:2025-03-13

Brand: AMI
Model: 221R
Description: The AMI MODEL 221R is the gold standard for oxygen deficiency & confined space oxygen monitoring. It is used by the thousands in US Government Laboratories, Space Agencies, Universities and a broad ra
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Product Details

MODEL 221R Oxygen Deficiency Monitors Description：

Operator Manual Data Sheet AMI Overview

Features & Benefits

1.Special Safety Features

Rechargeable battery backup with low power alarm, tamper-resistant alarm setpoints to prevent user override, calibrations error detection, and front panel lock-out.

2.Washdown-Ready Metal Enclosure

The powder-coated aluminum enclosure of the Analyzer is designed to provide protection against ingress of dust and water from low pressure spray. Design protects analyzers in difficult industrial environments and allows for low pressure washdown of the unit.

3.Audible Alarms & Relays

Detection of an Oxygen-Deficient environment will trigger a 95 dB alarm to warn of danger. Additionally, includes relays for triggering safety beacons or exhaust fans.

4.10-Year Sensor Life

The Zirconium Oxide Sensor provides up to 10-years of operational life while only requiring simple, periodic calibration. Detection technology is IDEAL for monitoring oxygen safety levels. Maintains accuracy over wide temperature range and not affected by changes in barometric pressure.

5.Optional Remote Probe

Allows monitoring of locations away from the control unit. Comes standard with a 12 ft (3.6m) cable but can be extended by the customer up to 300 ft (91.4m).

Technical Specifications

Physical & Eletrical Specifications
WEIGHT	MOUNTING	GAS CONNECTIONS	DIGITAL DISPLAY
4.0 lbs (1.8 kg)	Wall mount	Diffusion screen. No pump, sample tubing or fittings required	4-digit LCD (reads full scale from 0.0% to 25.0%)
POWER		OUTPUTS
100 –240 VAC < 11 Watts. Battery back-up provides 1 hour of power		4 – 20 mA isolated output signal Bi-directional RS485 communication

2-year warranty for Parts & Labor for any defects in materials or workmanship. 2-year Warranty for zirconium oxide sensors.

Operational Specifications
MEASUREMENT RANGE	AMBIENT OPERATIONAL TEMPERATURE RANGE	METHOD OF MEASUREMENT
0 –25.0%	+14°F to +122°F (-10°C to +50°C)	Zirconium Oxide Sensor (10-year life expectancy)

Monitor Performance Specifications
Minimum detection limit	90% UPSCALE RESPONSE TIMES FOR SPECIFIC RANGES	REPEATABILITY	Diurnal Temperature Specification	APPROVALS
0.05% of Oxygen	<12 sec for 0.0% – 25.0%	±0.1% of range or ±0.1% of oxygen whichever is greater	<±1% of scale over temperature range	UL 61010-1 for Safety Electrical Equipment CE Marked, Designed to Meet IP65

Analyzer Key Features
TAMPER RESISTANT PRESET ALARMS	OSHA Preset Standard Alarms Below 19.5% Oxygen Danger Level — Red warning light, 95 dB audible alarm, Relay 2 de-energized Above 23.5% Oxygen Enriched Level — Red warning light, 95 dB audible alarm, Relay 1 & 2 de-energized Additional Preset Alarm Below 20.0% Oxygen Caution Level — Yellow caution light, Relay 1 de-energized
WASH DOWN READY	Designed to withstand direct water spray
SAFETY FEATURES	1-hour rechargeable battery back-up Tamper-resistant alarm setpoints Front panel lock-out Calibration error detection and alarm
ACCESSORIES	Remote Sensing Probe for monitoring up to 300 ft from control unit Pre-wired Type B wall plug
COMMAND CENTER SOFTWARE	Included Software, which provides access to advanced functions: Calibration history Alarm configurations Data Log history of O2 measurements, power history Security settings