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<Installation and Operating Precautions for TIIS Flameproof Equipment>

EX-B03E

• 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, non-hardening
sealant such as liquid gaskets shall thus be applied to those
threads for ensuring waterproofness.

• If metal conduits need

exibility, use

ameproof

exible

ttings.

6. Maintenance

Flameproof

Apparatus

To maintain the

ameproof apparatus, do the following. (For

details, see Chapter 10 “MAINTENANCE OF EXPLOSION-
PROTECTED ELECTRICAL INSTALLATION” in the USER’S
GUIDELINES for Electrical Installations for Explosive Gas
Atmospheres in General Industry.)

(1) Maintenance servicing with the power on.

Flameproof apparatus shall not be maintenance-serviced with
its power turned on. However, in cases where maintenance
servicing is to be conducted with the power turned on, with
the equipment cover removed, always use a gas detector
to check that there is no explosive gas in that location. If it
cannot be checked whether an explosive gas is present or not,
maintenance servicing shall be limited to the following two items:
(a) Visual inspection

Visually inspect the

ameproof apparatus, metal conduits,

and cables for damage or corrosion, and other mechanical
and structural defects.

(b) Zero and span adjustments

These adjustments should be made only to the extent that
they can be conducted from the outside without opening the
equipment cover. In doing this, great care must be taken not
to cause mechanical sparks with tools.

(2) Repair

If the

ameproof apparatus requires repair, turn off the power

and transport it to a safety (non-hazardous) location. Observe
the following points before attempting to repair the apparatus.
(a) Make only such electrical and mechanical repairs as will

restore the apparatus to its original condition. For the

ameproof apparatus, the gaps and path lengths of joints

and mating surfaces, and mechanical strength of enclosures
are critical factors in explosion protection.
Exercise great care not to damage the joints or shock the
enclosure.

(b) If any damage occurs in threads, joints or mating surfaces,

inspection windows, connections between the transmitter
and terminal box, shrouds or clamps, or external wiring
connections which are essential in

ameproofness, contact

Yokogawa Electric Corporation.

CAUTION

Do not attempt to re-process threaded connections or re

nish

joints or mating surfaces.

ed, the electrical circuitry and

internal mechanisms may be repaired by component
replacement, as this will not directly affect the requirements
for

ameproof apparatus (however, bear in mind that the

apparatus must always be restored to its original condition).
If you attempt to repair the

ameproof apparatus, company-

speci

ed components shall be used.

(d) Before starting to service the apparatus, be sure to check all

parts necessary for retaining the requirements for

ameproof

apparatus. For this, check that all screws, bolts, nuts, and
threaded connections have properly been tightened.

(3) Prohibition of specifi cation changes and

modifi cations

Do not attempt to change speci

cations or make modi

cations

involving addition of or changes in external wiring connections.

7. Selection of Cable Entry Devices for Flameproof

Type

IMPORTANT

The cable glands (cable entry devices for

ameproof type)

conforming to IEC Standards are certi

ed in combination

with the

ameproof apparatus. So, Yokogawa-speci

ed cable

entry devices for

ameproof type shall be used to meet this

demand.

References:

(1) Type Certi

cate Guide for Explosion-Protected Construction

Electrical Machinery and Equipment (relating to Technical
Standards Conforming to International Standards), issued by
the Technical Institution of Industrial Safety, Japan

(2) USER’S GUIDELINES for Electrical Installations for

Explosive Gas Atmospheres in General Industry (1994),
issued by the Japanese Ministry of Labour, the Research
Institute of Industrial Safety.