Dräger Polytron 2 IR fixed gas detector

Dräger Polytron 2 IR fixed gas detector 8315629 EX 334

Dräger Polytron 2 IR fixed gas detector 8315629 EX 334

The Dräger Polytron IR is an explosion proof infrared gas detector for continuous monitoring of combustible gases and vapors. With its stainless steel body and drift free optics this gas detector is built for harsh offshore environments. Two models working with different wavelengths cover a broad range of detectable substances.

TECHNICAL INNOVATION

The model type 340 extends the area of applications for the Dräger Polytron IR product line. The different wavelength of the Dräger Polytron IR type 340 offers detection of alkanes at an even higher sensitivity. The possible monitoring of cyclohexane presents one of various options for gas detection resulting from this innovation. With both transmitter models Dräger Polytron IR type 340 and type 334, Dräger defines the status quo of measurement technology for continuous monitoring of ambient air regarding combustible gases and vapors. The Dräger Polytron IR works based on the physical principle of infrared absorption. The innovative double compensating and non-focussing optics effectively compensates temperature and ageing effects. With its many field proved components it sets the standard for safety relevant measurement requirements. It is approved by certification that the Dräger Polytron IR can be used for SIL 2 (safety integrity level) safety functions.

CONFIGURATION

Flexible is the configurable measuring range for the Dräger Polytron IR: Type 334 offers 0 to 20 %LEL and up to 100 %LEL, alternatively 0 to 100 %v/v for methane. For the type 340, the full scale is configurable from 5 to 100 %LEL. Configuration is menu guided and easy to perform, using a HART® handheld terminal.

CALIBRATION

For the easy calibration of the Dräger Polytron IR, one gas needs to be selected from an internal list, and this gas can differ from the gas to be measured. All data will be converted automatically to the substance to be monitored. So, the intricate use of factors for cross sensitivity calibration is no longer necessary. Thus for all Dräger Polytron IR transmitters there is only one calibration gas required, independent of the substance to be monitored.

STAND-BY MODE (PREVENTIVE MAINTENANCE FUNCTION)

Using a preventive maintenance function – stand-by mode – the Dräger Polytron IR does not immediately shutdown in case of dirty optics. Prior to providing a beam block fault signal, there will be a warning transmitted to the control system. The measurement continues in the background, and it will be switched back to normal operation when measuring gas concentrations of more than 15 %LEL. Alarming in a hazardous situation and with it the complete safety functionality will be maintained.

Type

Explosion proof gas detector with infrared sensor technology 

Gases and ranges

Longterm stability (drift)

Combustible gases 0 to 5 … 100 %LEL (depending on substance)

and vapors 0 to 350 … ppm (depending on substance)

Methane 0 to 100 %v/v (type 334 only)

< 2 %LEL (measuring range 0 to 100 %LEL methane) / 2 years 

Repeatability

< 2 %LEL (measuring range 0 to 100 %LEL methane) 

Response time t0…90

< 5 seconds 

Output signal analog

4 to 20 mA 

Output signals digital

HART®, RS 485 

Preventive maintenance function

2 mA in case of dirty optics 

Fault signal

Power supply

< 1.2 mA 

Signals for warning and maintenance configurable 

15 to 30 VDC, < 5 W, 3-wire 

Ambient conditions

Enclosure

Temperature

– 40 to +65 °C / – 40 to +150 °F (UL variants)

– 40 to +60 °C / – 40 to +140 °F (IECEx variants

Pressure

700 to 1300 hPa / 23.6 to 32.5 inch Hg 

Humidity

0 to 100 %RH, non-condensing 

IP 66 and IP 67, NEMA 4 and 7

Size

125 mm x 180 mm x 155 mm / 4.9'' x 7.1'' x 6.1'' (W x H x D) 

Weight

3.1 kg 

Approvals

UL, CSA Class 1, Div 1, Groups B, C, D 

ATEX II 2G EEx de [ia] IIC T5, II 2D IP 6X T100°C EN 50281-1-1 

IECEx Ex de [ia] IIC T5, Ex tD A21 IP6X T100°C

Explosion protection and performance approval 

EN 61779-1 

EN 61779-4 

EN 50271 

CE-mark: electromagnetic compatibility (directive 2004/108/EC)