Operation Manual

2-4

IM 1F5B2-01E

2.6 Precautions Regarding Use of Transceivers

IMPORTANT

• ULTRA YEWFLO is designed with full consideration of and measures against

interference from high-frequency noise. It is likely, however, that ULTRA YEWFLO

is affected by such noise if you use a transceiver near the instrument or the cable

wired to it. When using a transceiver, assess its influence on the loop where ULTRA

YEWFLO is connected by first locating it a few meters away from the ULTRA

YEWFLO’s converter component and then bringing it gradually closer in. Use the

transceiver at distances that do not cause a problem.

2.7 Precautions Regarding Insulation Resistance and

Withstanding Voltage Tests

• Insulation resistance and withstanding voltage tests can deteriorate insulation and

degrade safety even if the testing voltages are at levels that may not cause the

insulation to break down. Keep the application of these tests to a minimum.

• During insulation resistance testing, do not apply voltages exceeding 500 V DC.

• During withstanding voltage testing, do not apply voltages exceeding 500 V AC.

• Follow the procedures summarized below to run these tests. During testing, leave the

cable of the transmission line disconnected.

• Insulation Resistance Test Procedure

<1> Wire a cross-over cable from the SUPPLY "+" terminal through the PULSE "+"

to "-" terminals.

<2> Connect an insulation resistance meter (with the power switched off) between

the cross-over cable and the grounding terminal. Use the cross-over cable as the

positive-polarity test point and the grounding terminal as the negative-polarity

test point.

<3> Turn on the insulation resistance meter and measure the insulation resistance.

<4> After the completion of testing, remove the insulation resistance meter, connect a

100-kΩ resistor across the cross-over cable and the grounding terminal, and

allow at least one second for the accumulated electricity to discharge. (Do not

touch the terminals during discharge.)

• Withstanding Voltage Test Procedure

<1> Wire a cross-over cable from the SUPPLY "+" terminal through the PULSE "+"

to "-" terminals.

<2> Connect a withstanding voltage tester between the cross-over cable and the

grounding terminal. Connect the ground-side terminal to the grounding terminal.

<3> Gradually raise the testing voltage from 0 V to the specified level.

<4> Keep the voltage at the specified level for one minute.

<5> After the completion of testing, gradually lower the testing voltage to prevent a

power surge.