Dräger Pulsar 7000 Serie Instrucciones De Uso página 8

en Description
3.2 Feature description
3.2.1 General information
The Dräger Pulsar 7000 Series includes various gas warning systems. The system is available in the following variants:
Dräger Pulsar 7000 Series – Open Path Gas Detector

Dräger Pulsar 7000 Series – Duct Mount Gas Detector

Combustible hydrocarbons absorb a certain wavelength range of the infrared radiation. The gas warning system uses this property.
Each gas warning system consists of a transmitter and a receiver. The transmitter generates infrared light using several Xenon
light sources and radiates it in pulses. Optical sensors in the receiver detect whether or not a gas cloud containing hydrocarbons
in the measuring path between the transmitter and receiver is absorbing part of the infrared radiation. The intensity of the infrared
radiation arising at the receiver is converted into analog current signals. The receiver transfers the signals to a control unit (e.g.
®
Dräger REGARD 7000) via a 4 to 20 mA interface. The 4 to 20 mA interface features a configurable zero capture range. Minor
variations or signal noise within this range are set to exactly 4 mA.
The gas warning system measures an integral gas concentration in the measuring path. The signal that the receiver sends to the
control unit is proportional to the measured integral gas concentration. Depending on which gas warning system is used, the
receivers are factory-calibrated to different gases:
Methane/propane: Pulsar 7700 RX

Ethylene: Pulsar 7900 RX

Influences from rain, snow or contamination on the lenses are almost completely compensated for by the measurement of a
reference wavelength of the infrared radiation.
The optics of transmitter and receiver is equipped with a heating to optimize performance if ice, snow or condensation is present.
For communication purposes between transmitter and receiver, a DIGITAL LINK connection may be installed. Via this DIGITAL
LINK connection, the receiver can increase both signal strength and flash frequency in the transmitter (strong mode). This means
that adverse environmental influences can be compensated for to a certain degree. Without a DIGITAL LINK connection, no
communication is carried out between the transmitter and receiver. This means that the system has the following limitations:
Strong mode not available

Longer response times (see section 8 on page 26)

Measured values are updated at rare intervals only

Restricted operation while in alignment mode

Dräger recommends using the DIGITAL LINK connection.
Transmitters and receivers are configured for different ranges. Depending on the required measuring distance, the components
can be combined as follows:
Transmitter
Pulsar 7000 TX S (15 ft. to 200 ft.)
(4 m - 60 m)
Pulsar 7000 TX L (100 ft. to 650 ft.)
(30 m - 200 m)
Pulsar 7000 TX S (15 ft. to 200 ft.)
(4 m - 60 m)
Pulsar 7000 TX L (100 ft. to 650 ft.)
(30 m - 200 m)
Pulsar 7000 TX S (15 ft. to 200 ft.)
(4 m - 60 m)
Pulsar 7000 TX L (100 ft. to 650 ft.)
(30 m - 200 m)
8
Pulsar 7700 RX S (15 ft. to 390 ft./4 m - 120 m, methane, propane)
without DIGITAL LINK connection
15 ft. to 200 ft.
(4 m - 60 m)
100 ft. to 390 ft.
(30 m - 120 m)
Pulsar 7700 RX L (320 ft. to 650 ft./100 m - 200 m, methane, propane)
-
320 ft. to 390 ft.
(100 m - 120 m)
Pulsar 7900 RX S (15 ft. to 390 ft./4 m - 120 m, ethylene)
15 ft. to 100 ft.
(4 m - 30 m)
100 ft. to 200 ft.
(30 m - 60 m)
Receiver
with DIGITAL LINK connection
15 ft. to 200 ft.
(4 m-60 m)
100 ft. to 390 ft.
(30 m - 120 m)
-
320 ft. to 650 ft.
(100 m - 200 m)
15 ft. to 200 ft.
(4 m - 60 m)
100 ft. to 390 ft.
(30 m - 120 m)