Caution, Warning – Yokogawa EJX115A User Manual

Page 11

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<2. Handling Cautions>

2-3

IM 01C25K01-01E

(b) Never apply a voltage exceeding 500 V DC

(100 V DC with an internal lightning protector)

for the insulation resistance test, nor a voltage

exceeding 500 V AC (100 V AC with an internal

lightning protector) for the dielectric strength

test.

(c) Before conducting these tests, disconnect

all signal lines from the transmitter terminals.

The procedure for conducting these tests is as

follows:

• Insulation Resistance Test

1) Short-circuit the + and – SUPPLY terminals in

the terminal box.

2) Turn OFF the insulation tester. Then connect

the insulation tester plus (+) lead wire to the

shorted SUPPLY terminals and the minus (–)

leadwire to the grounding terminal.

3) Turn ON the insulation tester power and

measure the insulation resistance. The voltage

should be applied as briefly as possible to verify

that the insulation resistance is at least 20 MΩ.

4) After completing the test and being very careful

not to touch exposed conductors disconnect the

insulation tester and connect a 100 kΩ resistor

between the grounding terminal and the short-

circuiting SUPPLY terminals. Leave this resistor

connected at least one second to discharge any

static potential. Do not touch the terminals while

it is discharging.

• Dielectric Strength Test

1) Short-circuit the + and – SUPPLY terminals in

the terminal box.

2) Turn OFF the dielectric strength tester. Then

connect the tester between the shorted

SUPPLY terminals and the grounding terminal.

Be sure to connect the grounding lead of the

dielectric strength tester to the ground terminal.

3) Set the current limit on the dielectric strength

tester to 10 mA, then turn ON the power and

gradually increase the test voltage from ‘0’ to

the specified voltage.

4) When the specified voltage is reached, hold it

for one minute.

5) After completing this test, slowly decrease the

voltage to avoid any voltage surges.

2.9 Installation of an Explosion-

Protected Instrument

NOTE

For FOUNDATION Fieldbus explosion protected

type, please refer to IM 01C22T02-01E.

For PROFIBUS PA explosion protected type,

please refer to IM 01C25T04-01EN.

If a customer makes a repair or modification to

an intrinsically safe or explosionproof instrument

and the instrument is not restored to its original

condition, its intrinsically safe or explosionproof

construction may be compromised and the

instrument may be hazardous to operate. Please

contact Yokogawa before making any repair or

modification to an instrument.

CAUTION

This instrument has been tested and certified

as being intrinsically safe or explosionproof.

Please note that severe restrictions apply to this

instrument’s construction, installation, external

wiring, maintenance and repair. A failure to abide

by these restrictions could make the instrument a

hazard to operate.

WARNING

Maintaining the safety of explosionproof

equipment requires great care during mounting,

wiring, and piping. Safety requirements also

place restrictions on maintenance and repair.

Please read the following sections very carefully.

WARNING

The range setting switch must not be used in a

hazardous area.

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