YOKOGAWA EY200, Руководство пользователя

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<2> Earth Voltage Measurement (Series interference voltage): ~V
Set the range switch to Earth voltage (˜V) position in the
condition of <1>.
Earth voltage will be indicated on the display. Make sure
that the voltage is 3V or less.
When the display reads more than 3V, it may result in
excessive errors in earth resistance measurement. To avoid
this, make measurement after reducing the voltage by
turning off the power supply of the equipment under test
etc.
<3> Earth resistance (
Ω
) Measurement: Simplified Measurement
Set the range switch to 2000Ω position and press the test
button (Ω measurement.).
LED remains illuminated during testing. Turn the range
switch to 200Ω and 20Ω when the earth resistance is low.
This indicated value is the earth resistance of the earthed
equipment under test.
<Note>
• If the auxiliary earth resistance of auxiliary earth spike
C is too high to make measurement, the display reads
' . . . '. Recheck the connection of test leads and the earth
resistance of auxiliary earth spike.
<4> Simplified Measurement Value
Two-pole(wire) method is used for simplified measurement.
In this method, earth resistance value re of earth electrode
connected to terminal P is added to true earth resistance
value Rx and shown as an indicated value Re.
Re = Rx + re
If the re is known beforehand, true earth resistance value
Rx is calculated as follows.
Rx = Re - re