Thermo Scientific HB-S200, Руководство пользователя

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Sarasota 200 Ultrasonic Multipath
Flowmeter
Appendix 5 I.S Interface and Transducer Page A5-1 Thermo Fisher Scientific
APPENDIX 5
INTRINSICALLY SAFE TRANSDUCERS AND INTERFACE UNIT.
Introduction.
The Sarasota 200 Intrinsically safe system comprises a Transducer Type No: 01500-IST and an
Interface Unit Type No: 01500-ISI. These two items are certified as a single entity and are intended for
use with each other.
The transducer is dimensionally identical to the standard 1 MHz unit and is mounted in the same
manner on a rack assembly which is positioned to propagate ultrasound in the hazardous area. It has
additional energy limiting components potted in the housing adjacent to the piezo ceramic disc to
prevent excessive voltages being generated from mechanical impact under fault conditions. It is
labelled with specifications and manufacturers data.
The Interface unit is contained in a surface mounting enclosure with terminal block connections. It
contains components to prevent the transfer of excessive energy from the safe area to the hazardous
area where ignition may be caused. The unit is mounted remote from the transducer in the safe area and
is labelled with specifications and manufacturers data. The maximum permissible cable length between
the transducer and interface is 100 meters
The general installation instructions as contained in the main body of the manual apply but for the IS
system additional precautions and instructions apply.
Installation guidelines for Hazardous Areas.
The Sarasota 200 IS Transducer and Interface Unit has been designed such that it will not give rise to
physical injury when handled properly. Neither item produces excessive surface temperature and they
do not emit infra red, electromagnetic or ionising radiation.
Before starting installation work ensure all power connections are isolated and precautions taken to
prevent power being restored while work is taking place. Hazardous area installations forbid the use of
tools or equipment which could produce an explosion hazard by causing a spark or imposing excessive
mechanical stress.
Each item must be installed in a manner to avoid exposure to thermal or mechanically induced stresses
and in addition neither item should be exposed to chemically aggressive substances beyond the
expected levels in a sewage treatment installation or aqueous industrial outflows. The Sarasota 200 IS
Transducer and Interface is not intended to be exposed to significant conditions of dust build up.
In cases where impact or other mechanical forces may be expected appropriate methods of protection
must be used. Details of permissible installation conditions (ambient temperature, maximum surface
temperature and gas groups) are provided on the labels affixed. This equipment must only be installed
in hazardous areas appropriate to the method of protection.
Marking.
The Sarasota 200 IS Transducer and Interface unit are marked for use in hazardous areas in accordance
with the ATEX Directive. The transducer is considered as part of the interface. Each item is marked as
follows:
IS Transducer: [Epsilon x] II 2 G EEx ib IIB T4 Installed in the hazardous area
Intrinsically safe protection: ib. Apparatus Group II, Area Category 2 G, Gas Group IIB, T4 Surface
temperature class at an ambient temperature of 40 Deg C
IS Interface: [Epsilon x] II (2) G [EEx ib] IIB Installed in the safe area
Intrinsically safe protection: ib. Apparatus Group II, Area Category 2 G, Gas Group IIB, T4 Surface
temperature class at an ambient temperature of 40 Deg C
[Epsilon x] is marked on the label as shown below.
Maintenance.
The Sarasota 200 IS Transducer and Interface is maintenance free and in the event of a fault condition
developing cannot be serviced. No repair should be attempted to installed items, faulty assemblies
should be replaced with an identical replacement
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