YOKOGAWA AXFA14G - Page 87

<INSTALLATION AND OPERATING PRECAUTIONS FOR TIIS FLAMEPROOF EQUIPMENT>
86
EX-B03E
4. Installation of Flameproof
Apparatus
(1) Installation Area
Flameproof apparatus may be installed, in accordance
with applicable gases, in a hazardous area in Zone 1 or 2,
wherethespeciedgasesarepresent.Thoseapparatus
shall not be installed in a hazardous area in Zone 0.
Note: Hazardousareasareclassiedinzonesbasedupon
the frequency of the appearance and the duration of an
explosive gas atmosphere as follows:
Zone 0: An area in which an explosive gas atmosphere
is present continuously or is present for long
periods.
Zone 1: An area in which an explosive gas atmosphere is
likely to occur in normal operation.
Zone 2: An area in which an explosive gas atmosphere
is not likely to occur in normal operation and if it
does occur it will exist for a short period only.
(2) Environmental Conditions
The standard environmental condition for the installation
ofameproofapparatusislimitedtoanambient
temperature range from –20°C to +40°C (for products
certiedunderTechnicalCriteria).However,someeld-
mountedinstrumentsmaybecertiedatanambient
temperature up to +60°C as indicated on the instrument
nameplates.Iftheameproofapparatusareexposed
to direct sunshine or radiant heat from plant facilities,
appropriate thermal protection measures shall be taken.
5. External Wiring for Flameproof
Apparatus
Flameproofapparatusrequirecablewiringorameproof
metal conduits for their electrical connections. For
cable wiring, cable glands (cable entry devices for
ameprooftype)towiringconnectionsshallbeattached.
Formetalconduits,attachsealingttingsascloseto
wiring connections as possible and completely seal the
apparatus. All non-live metal parts such as the enclosure
shallbesecurelygrounded.Fordetails,seethe“USER’S
GUIDELINES for Electrical Installations for Explosive Gas
AtmospheresinGeneralIndustry,”publishedin1994.
(1) Cable Wiring
• For cable wiring, cable glands (cable entry devices
forameprooftype)speciedorsuppliedwiththe
apparatus shall be directly attached to the wiring
connections to complete sealing of the apparatus.
• Screws that connect cable glands to the apparatus
arethoseforG-typeparallelpipethreads(JISB0202)
with no sealing property. To protect the apparatus
from corrosive gases or moisture, apply nonhardening
sealant such as liquid gaskets to those threads for
waterproong.
• Speciccablesshallbeusedasrecommendedby
the“USER’SGUIDELINESforElectricalInstallations
forExplosiveGasAtmospheresinGeneralIndustry,”
published in 1994.
• In necessary, appropriate protective pipes (conduit
orexiblepipes),ductsortraysshallbeusedfor
preventing the cable run (outside the cable glands)
from damage.
• To prevent explosive atmosphere from being
propagated form Zone 1 or 2 hazardous location
to any different location or non-hazardous location
through the protective pipe or duct, apply sealing
of the protective pipes in the vicinity of individual
boundaries,orlltheductswithsandappropriately.
• When branch connections of cables, or cable
connections with insulated cables inside the conduit
pipesaremade,aameprooforincreased-safety
connectionboxshallbeused.Inthiscase,ameproof
or increased-safety cable glands meeting the type of
connection box must be used for cable connections to
the box.
(2) Flameproof Metal Conduit Wiring
• Fortheameproofmetalconduitwiringorinsulated
wires shall be used as recommended by the USER’S
GUIDELINES for Electrical Installations for Explosive
Gas Atmospheres in General Industry, published in
1994.
• For conduit pipes, heavy-gauge steel conduits
conformingtoJISC8305Standardshallbeused.
• Flameproofsealingttingsshallbeusedinthevicinity
ofthewiringconnections,andthosettingsshallbe
lledwithsealingcompoundstocompletesealing
of the apparatus. In addition, to prevent explosive
gases,moisture,oramecausedbyexplosionform
being propagated through the conduit, always provide
sealingttingstocompletesealingoftheconduitin
the following locations:
(a) In the boundaries between the hazardous and
non-hazardous locations.
(b) In the boundaries where there is a different
classicationofhazardouslocation.
• For the connections of the apparatus with a conduit
pipe or its associated accessories, G-type parallel
pipethreads(JISB0202)shallbeusedtoprovide
aminimumofve-threadengagementtocomplete
tightness. In addition, since these parallel threads
do not have sealing property, nonhardening sealant
such as liquid gaskets shall thus be applied to those
threads for ensuring waterproofness.
• Ifmetalconduitsneedexibility,useameproof
exiblettings.