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<Installation and Operating Precautions for TIIS Flameproof Equipment>

EX-B03E

Installation and Operating Precautions for TIIS Flameproof Equipment

Apparatus Certifi ed Under Technical Criteria (IEC-compatible Standards)

1. General

The following describes precautions on electrical apparatus of

ameproof construction (hereinafter referred to as

ameproof

apparatus) in explosion-protected apparatus.
Following the Labour Safety and Health Laws of Japan,

ameproof apparatus is subjected to type tests to meet either

the technical criteria for explosionproof electrical machinery and
equipment (standards noti

cation no. 556 from the Japanese

Ministry of Labour) (hereinafter referred to as technical criteria),
in conformity with the IEC Standards, or the “Recommended
Practice for Explosion-Protected Electrical Installations in
General Industries,” published in 1979. These certi

ed apparatus

can be used in hazardous locations where explosive or
in

ammable gases or vapours may be present.

Certi

ed apparatus includes a certi

cation label and an

equipment nameplate with the speci

cations necessary for

explosion requirements as well as precautions on explosion
protection. Please con

rm these precautionary items and use

them to meet speci

cation requirements.

For electrical wiring and maintenance servicing, please refer
to “Internal Wiring Rules” in the Electrical Installation Technical
Standards as well as “USER’S GUIDELINES for Electrical
Installations for Explosive Gas Atmospheres in General
Industry,” published in 1994.
To meet

ameproof requirements, equipment that can be termed

“

ameproof” must:

(1) Be certi

ed by a Japanese public authority in accordance

with the Labour Safety and Health Laws of Japan and have
a certi

cation label in an appropriate location on its case,

and

(2) Be used in compliance with the speci

cations marked on its

certi

cation label, equipment nameplate and precautionary

information furnished.

2. Electrical Apparatus of Flameproof Type of

Explosion-Protected Construction

Electrical apparatus which is of

ameproof construction is

subjected to a type test and certi

ed by the Japanese Ministry

of Labour aiming at preventing explosion caused by electrical
apparatus in a factory or any location where in

ammable gases

or vapours may be present. The

ameproof construction is

of completely enclosed type and its enclosure shall endure
explosive pressures in cases where explosive gases or
vapours entering the enclosure cause explosion. In addition,
the enclosure construction shall be such that

ame caused

by explosion does not ignite gases or vapours outside the
enclosure.
In this manual, the word "

ameproof" is applied to the

ameproof

equipment combined with the types of protection "e", "o", "i", and
"d" as well as

ameproof equipment.

3. Terminology

(1) Enclosure

An outer shell of an electrical apparatus, which encloses live
parts and thus is needed to con

gure explosion-protected

construction.

(2) Shroud

A component part which is so designed that the fastening of joint
surfaces cannot be loosened unless a special tool is used.

(3) Enclosure internal volume

This is indicated by:— the total internal volume of the

ameproof

enclosure minus the volume of the internal components essential
to equipment functions.

(4) Path length of joint surface

On a joint surface, the length of the shortest path through
which

ame

ows from the inside to outside of the

ameproof

enclosure. This de

nition cannot be applied to threaded joints.

(5) Gaps between joint surfaces

The physical distance between two mating surfaces, or
differences in diameters if the mating surfaces are cylindrical.

Note: The permissible sizes of gaps between joint surfaces, the path

length of a joint surface and the number of joint threads are
determined by such factors as the enclosure’s internal volume,
joint and mating surface construction, and the explosion
classi

cation of the speci

ed gases and vapours.

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 non-hardening sealant such as liquid
gaskets to those threads for waterproo

ng.