7 notes for saftey, Notes for saftey -2, Caution – Yokogawa YVP110 User Manual

Page 13

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<1. Notes on Handling>

1-2

IM 21B04C01-01E

1.6 Insulation Resistance Test

and Withstand Voltage Test

CAUTION

(1) Overvoltage of the test voltage that is so

small that it does not cause an dielectric

breakdown may in fact deteriorate insulation

and lower the safety performance; to prevent

this it is recommended that the amount of

testing be kept to a minimum.

(2) The voltage for the insulation resistance test

must be 500V DC or lower, and the voltage

for the withstand voltage test must be 500V

AC or lower. Failure to heed these guidelines

may cause faulty operation.

(3) Where a built-in arrester is provided (suffix

code: /A), the voltage for the insulation

resistance test must be 100V DC or lower,

and the voltage for the withstand voltage test

must be 100V AC or lower. Failure to heed

these guidelines may cause faulty operation.

Follow the steps below to perform the test, the

wiring of the communication line must be removed

before initiating testing.

Insulation resistance test procedure

1. Lay transition wiring between the + terminal and

the − terminal.

2. Connect the insulation resistance meter (with

the power turned OFF) between the transition

wiring of Step 1 above and ground terminal.

The polarity of the input terminals must be

positive and that of the ground must be

negative.

3. Turn the power of the insulation resistance

meter ON and measure the insulation

resistance. The duration of the applied voltage

must be the period during which 100 MΩ

or more is confirmed (or 20 MΩ if the unit is

equipped with a built-in arrester).

4. Upon completion of the test, remove the

insulation resistance meter, connect a 100

kΩ resistor between the transition wiring, and

allow the electricity to discharge. Do not touch

the terminal with your bare hands while the

electricity is discharging for more than one

second.

Withstand voltage test procedure

Testing between the input terminals and the

grounding terminal

1. Lay the transition wiring between the + terminal

and the − terminal, and connect the withstand

voltage tester (with the power turned OFF)

between the transition wiring and the grounding

terminal. Connect the grounding side of the

withstand voltage tester to the grounding

terminal.

2. After setting the current limit value of the

withstand voltage tester to 10 mA, turn

the power ON, and gradually increase the

impressed voltage from 0 V to the specified

value.

3. The voltage at the specified value must remain

for a duration of one minute.

4. Upon completion of the test, carefully reduce

the voltage so that no voltage surge occurs.

1.7 Notes for Saftey

CAUTION

When air is supplied to a valve, do not touch

the moving part (a stem of the valve), as it may

suddently move.

CAUTION

• While A/M selection switch is set to manual

side (M), the pressure set in the regulator

for air supply will be directly output to the

actuator regardless of the control signal.

Before changing the mode from auto to

manual, check and confirm thoroughly that

there will be no effect which may cause

a danger in process or personal injury by

changing the mode.

• Do not change the mode by using auto/

manual switch during the operation. If the

mode is changed from auto to manual or

manual to auto, the valve stem will happnen

to move to the position which is different

from the control signal (the input signal to the

positioner), and thus dangerous.

• As soon as the manual operation is finished,

make it sure to change the mode to auto by

moving the A/M selection switch to Auto(A)

side.

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