Table of Contents
Advertisement
Secure the analyzer and the Ex px safety equipment in accordance with your dimensional
drawings in section Connection diagrams (Page 37), and connect them as shown in the
assembly diagrams 4-2 and 4-3. The following information applies to use of the Ex px safety
equipment recommended by us in accordance with our current Catalog AP01. This information
applies accordingly to all other purging units.
It is essential that you observe the following conditions for trouble-free operation:
• When tightening union nuts on the gas couplings, use a suitable open-ended spanner to
achieve correct counterlocking; otherwise the danger exists that the gas path will leak.
• The operator must ensure the minimum pressure of the protective gases at the installation
site. An overpressure of 0.2 ... 0.4 MPa (2 ... 4 bar) must be applied at the pressure regulator
of the Ex px safety equipment.
• If the protective gas is discharged, the pressure drop over the line must not exceed 5 hPa
(5 mbar) at a flow of 50 l/min. To achieve this, the exhaust air line must be dimensioned
accordingly (e.g. for a pipe thread with inside diameter of ISO 228 - G 1, the length of the
exhaust air line should be about 20 m).
• The pre-purging time which can be set on the Ex px safety equipment (5 min with a protective
gas flow of 50 l/min) must not be changed (this is the minimum!).
• The Ex px safety equipment is delivered with fixed basic parameters. The protective gas
pressure is preset to 105 hPa (rel.). Reasonable changes to these parameters, such as
reduction of the maximum protective gas pressure, can only be made in accordance with the
specifications in the supplied manual for the Ex px safety equipment.
• Sample gas must not be supplied to the analyzer until the pre-purging phase has ended.
• A key switch can be connected to the Ex px safety equipment (see Key switch (Page 49) for
details).
• OXYMAT 6F: Before sample gas is fed in, the microflow sensor must be purged by reference
gas. Therefore the reference gas must also be connected (pre-purging period = 5 min) when
the Ex px safety equipment is switched on. The reference gas pressure must always be
0.2 ... 0.4 MPa (2 ... 4 bar) above the sample gas pressure.
For analyzer versions with leakage compensation, the following also applies:
For operation with combustible sample gases, the difference in pressure between the protective
gas and sample gas must be permanently and reliably kept at over 50 hPa (recommended 5 hPa).
Differential pressure monitoring must be provided for failure protection. This should ensure that
the Ex px safety equipment switches off the analyzer and goes into the pre-purging phase when
a set pressure difference is fallen below. It is up to the user to select a suitable differential
pressure monitoring device (e.g. differential pressure switch).
OXYMAT 6F: The sample gas inlet contains a restrictor that creates a dynamic pressure to
dampen pulsating flows. Removal of this restrictor may be advisable if differential pressure
monitoring (with leakage compensation) is to take place. The damping measure (restrictor)
should then be fitted upstream of the pressure measuring point if required.
Compact Operating Instructions in accordance with EN 61010-1 and EN 60079-0
Compact Operating Instructions, 09/2018, A5E45779389002-01
4.5 Analyzers for operation in hazardous areas
Connecting
41
Advertisement
Table of Contents
