Overview; Description Of Product; Description Of Function - Honeywell SEARCHLINE EXCEL PLUS Technical Manual

10 Chapter 3 Overview

3 Overview

3.1 Description of Product
Searchline Excel Plus & Searchline Excel Edge Open Path Flammable Hydrocarbon Gas Detectors provide enhanced safety
monitoring in the event of loss of containment of flammable hydrocarbon gases. Searchline Excel Plus & Searchline Excel
Edge help facilities protect people, plant and the environment against the hazards of flammable hydrocarbons. Their
strength is that they reliably detect a broad range of hydrocarbon gases and can do this in extremes of weather, even
through thick fog.
The new Searchline Excel is available in two versions:
• Searchline Excel Plus – Medium Range Safety Open-Path Flammable Hydrocarbon Gas Detector
• Searchline Excel Edge – Long Range Perimeter Monitoring Open-Path Flammable Hydrocarbon Gas Detector
Searchline Excel Plus & Searchline Excel Edge OPFHGD consist of a cooperative transmitter and receiver located
where a flammable hydrocarbon gas cloud could occur. The transmitter unit sends an infrared beam to the receiver unit.
Searchline Excel Plus and Searchline Excel Edge instruments detect a gas cloud that crosses this beam.
3.2 Description of Function
Searchline Excel Plus & Searchline Excel Edge flammable gas detectors operate on the principle of infrared absorption.
Gases absorb light at specific wavelengths depending on their molecular composition. Hydrocarbon gases absorb in
the infrared region of the electromagnetic spectrum. If a cloud of hydrocarbon gas is present, part of the infrared light
is absorbed by the gas, causing a reduction in the light energy that is proportional to the amount of gas in the beam.
The amount of absorption depends upon the size of the gas cloud impinging on the beam and upon the concentration of
that cloud.
Searchline Excel Plus & Searchline Excel Edge transmitter units produce a well-defined focused beam of infrared light and
the partner, co-operative receiver unit detects this beam and determines the amount of gas present and reacts accordingly.
Both units have advanced diagnostics built in. Each unit is housed in a robust stainless steel housing. The receiver
produces a 4–20 mA analogue output equivalent to 0–5 LEL.m (Lower Explosive Limit x meters) / 0–250,000 ppm.m
(parts per million x meters) of gas as well as a stepped level option and relay outputs and digital communications outputs.
Note
The infrared beam is invisible and eye safe.
The transmitter and receiver units incorporate intelligent heated optics designed to minimise the build-up of humidity,
condensation, snow or ice on the glass windows, that could obscure the optics in extreme conditions. In-built diagnostics
monitor the clarity of the transmitter and receiver windows. An advanced nano-technology coating on the windows helps
to maintain clarity.
The system is microprocessor controlled with advanced integral self-diagnostics and fault-finding facilities that drive
a status-based maintenance and extended cycle time.
Local indication of instrument status is provided via LEDs on the transmitter and a high visibility HALO light ring on
the receiver.
Local communication between an operator/technician and the gas detector system is via an associated Handheld Unit
that uses the receiver's inbuilt Bluetooth wireless serial link. The Handheld Unit provides the user with an advanced
user-friendly App supporting the Honeywell Fire and Gas Platform products with menu-style interface to select and invoke
commands for commissioning and configuring the system and for operator and maintenance viewing the system state and
measurements.
The Handheld Unit is connected to the receiver via wireless Bluetooth over a range of typically 20 m (66 ft) enabling simple
remote access.
The Fixed Platform App has been tested with Ecom Smart-EX02 mobile phone. Other phones and tablets running
Android 5.1 (Lollipop) or higher may work, but Honeywell does not guarantee full functionality.
Searchline Excel™ Plus / Searchline Excel™ Edge – Technical Manual