Information For Safe Use; Measuring Function For The Explosion Protection Acc. To 2014/34/Eu; Approvals - Dräger PEX 1000 Instrucciones De Uso

Description
2.3

Information for safe use

Only certified sensors or sensing heads are allowed to be connected to the terminals br/br, ge/
yw, and sw/bk of the PEX 1000.
The following notes apply during operation with the remote Dräger sensing heads
Polytron SE Ex PR ... DD/DQ and HT M DD/DQ (100 %LEL) and must be observed with
regards to the measuring function:
1. Basically, the measuring principle of heat of reaction which is based on the catalytic
oxidation of a flammable gas, is ambiguous because at high measuring gas concentrations
there is not enough oxygen in the sensor for the oxidation of the flammable gas. So the
measuring signal decreases at very high gas concentrations and can even lead to values
within the measuring range. A connected controller unit must be operated with display
devices, measuring value outputs (if available), and alarm thresholds operating self-
retaining if the measuring range is exceeded.
2. The measuring principle of heat of reaction requires a minimum oxygen concentration of
12 % by vol., otherwise the displayed measuring values will be too low because of oxygen
deficiency.
2.4 Measuring function for the explosion protection acc. to 2014/34/
EU
The PEX 1000 in combination with the sensing head Polytron SE Ex PR ... DD/DQ has been
approved in respect to the measuring function for explosion protection according to EN 60079-
29-1 for the following gases and vapours:
acetone, acetylene, ammonia, petrol 065/095 (FAM standard gasoline), benzene, 1.3-
butadiene, n-butane, n-butyl acetate, diethyl ether, dimethyl ether, ethanol, ethene (ethylene),
ethyl acetate, ethylene oxide, n-hexane, methane, methanol, methyl ethyl ketone (MEK),
methyl methacrylate, n-nonane, n-octane, n-pentane, propane, i-propanol, propene
(propylene), propylene oxide, toluene, hydrogen and o-xylene.
NOTICE
i i
Although the PEX 1000 has been factory-tested before delivery, the commissioning
after installation must include the zero point and sensitivity calibration.
The commissioning must be terminated by a function test of the complete gas
detection system.
2.5

Approvals

See Declaration of Conformity on Page 75.
24 Dräger PEX 1000