Introduction

The Simtronics GD1 sets a new standard for toxic gas detection. Using a tuneable laser diode, the GD1 delivers enhanced coverage and fail safe detection. The performance improvement marks a genuine step change for safety systems and life cycle cost savings.

The GD1 has been designed with features that provide an effective response to the detection of gas hazards in a wide range of industrial environments from offshore production facilities to wastewater treatment plants.At the heart of the detector is a tuneable laser diode that eliminates environmental effects from sun, rain and fog. The laser scans single absorption lines where there is no interference from other gases.

Unlike traditional methods for detecting H2S (MOS or EC cell) the GD1 needs no recalibration and can replace multiple standard detectors to cover the same risk. The complete optomechan ical design and construction is so stable that an ultra fast speed of response can be achieved whilst providing unparalleled service life and detector stability, thus saving on maintenance and service costs.

Supplied with worldwide hazardous area approvals. Suitable for use in systems with SIL 2 requirement.

Specifications

Type	Laser Open Path Gas Detector
Design principle	Near IR Laser Scanning
IR Source	Tuneable laser diode, Laser Class 1, eye safe
Calibrated gas	Hydrogen sulphide (H2S)
Detected gases	Target gas only
Calibrated range	0 – 200 ppm.m 0 - 500 ppm.m 0 - 1000 ppm.m 0 - 2000 ppm.m 0 - 5000 ppm.m 0- 50000 ppm.m
Path length	5 - 75m
PERFORMANCE
Zero point stability	±4%, Relative to full scale deflection (FS)
Span stability	±4% FS
Response time	5 sec
Tolerable Obscuration	98% (Allowable signal loss)
Calibration interval	Fixed factory calibrated. No field calibration required.
ELECTRICAL
Power supply	24V DC, (range 18 - 32V DC)
Power consumption	15W max (TX: 10W + Rx: 5W)
Cable entry	M25
Heated Optics	Yes
Junction box	Supplied with Exe junction box for Transmitter (Tx) and Receiver (Rx).
Connection	0.5 mm2 (20 AWG) - 2.5 mm2 (14 AWG), 3 wires
Analogue output signal	0-20mA, max. load impedance 500Ω. Optional LCD Display
Fault signalling	Diagnosis signalling in the 0.4 - 3.0mA range
Maintenance interface	HART v6.0 Universal Commands
ENVIRONMENT
Storage	-40°C to +75°C (-40°F to 167°F)
Operation	-40°C to +65°C (-4°F to 149°F)
ATEX flameproof	-55°C to +75°C (-67°F to 167°F)
Humidity	100% RH (non-condensing)
Ingress	IP66 / IP67  DIN 60529
RFI/EMI	Complies with EN 61000-6-2, EN 61000-6-4, EN 50270, EN 60945
HOUSING
Ex Classification	Tx/Rx: ATEX II 2 G EExd IIC T5 JB: ATEX II 2 G EEx e T6
Material	316 L stainless steel
Weight	Tx/Rx: 5.5 Kg (12 lbs),   JB: 2.0 Kg (4.4 lbs)
Dimensions	205L x 115W x 248H (mm),  8.1 x 4.3 x 9.8 (inches)
APPROVALS
ATEX	DNV 2008 ATEX 18877X
IECEX	DNV 10.0002X
Ingress	IP66/IP67 IEC 60529
SIL	Suitable for use in SIL2 systems