Model NGA2000 NDIR

Instruction Manual

748332-F April 2003

SECTION 1

DESCRIPTION AND SPECIFICATIONS

1-1 OVERVIEW

This manual describes the Non-Dispersive Infrared (NDIR) Analyzer Module of Rosemount Analytical's NGA2000 Series of gas analysis components.

The NDIR Analyzer Module is designed to continuously determine the concentration of oxygen in a flowing gaseous mixture. The concentration is expressed in one of three fashions:

•parts-per-million

•percent of composition

•percent of fullscale

The user can obtain an output that is linear with concentration by initiating a linearizer, which is based on a fourth-order polynomial. The linearizer is incorporated in the Analyzer Module's electronic circuitry and is adjustable through interconnection with the network.

The entire Analyzer Module is designed as a slide-in module (if configured in stand-alone instrument fashion), removable from the front of the Platform, with gas connections made from the rear. All electronics relative to sample detection and conditioning are included in this module.

1-2 TYPICAL APPLICATIONS

The NDIR Analyzer Module is designed to cover a wide range of process, stack and automotive applications. Typical measurements include:

Chemical and Petroleum

•Carbon dioxide: Manufacture of ethylene oxide, phthalic anhydride and ammonia; nitrogen generation; and producer gas monitoring

•Carbon Monoxide: Stack monitoring

•Methane: Ammonia manufacture

•Acetylene: Manufacture of acetylene, acrylonitrile, and vinyl chloride

•Sulfur Dioxide: Sulfuric acid stack gas

Food and Agriculture

•Carbon Dioxide and Water Vapor: Blanketing of perishables, fermentation processes, photosynthesis studies, personnel protection

Aerospace and Oceanography

•Carbon Dioxide, Carbon Monoxide, and Water Vapor: Diving and space chambers

Metals and Ceramics

•Carbon Dioxide: Monitoring of producer gas, steel converting, manufacture of cement, soaking pit, heat treating

•Carbon Monoxide: Inert gas generation, producer gas monitoring, rotary kiln roasting, tin plate annealing, steel converting, aluminum power processing, porcelain kilns, tunnels

•Water Vapor: Heat treating, hydrogen brazing, nickel and chrome plating

•Sulfur Dioxide: Flash smelting

•Ammonia: Ammonia dissociation

1-3 THEORY OF TECHNOLOGY

Inside of the Analyzer Module, two equal-energy infrared beams are directed through two parallel optical cells, a flow-through sample cell and a reference cell. The reference cell may be sealed or may contain a continuously flowing reference gas. (See Figure 1-1 below.)

The infrared radiation is interrupted by a chopper at a frequency of 5 Hz.

Rosemount Analytical Inc. A Division of Emerson Process Management

Description and Specifications 1-1