Iwatsu SS-281A-H Instruction Manual page 28

Chapter 4 Measurement
4.3.4 Handling of Rogowski Coil Sensor
The Rogowski Coil has a coil structure consisting of an extra-fine wire rod
wound tight around a wick material of Teflon tube. Avoid pulling or bending
the Rogowski Coil Sensor excessively as much as possible. The minimum
curvature radius of the coil is 5 mm. Application of excessive force to the
Rogowski Coil may cause plastic deformation of part of the coil. Use caution
when attaching and detaching the coil from a target to be measured.
Deformation of the coil structure will degrade the specifications of the sensor.
In order to measure current, the one end of the Rogowski Coil is required to
be inserted into the joint hole so that the coil forms a loop that circles around
the current to be measured. The insertion length of the coil is about 8 mm
from the joint hole end. Insert the Rogowski Coil until bumping.
WARNING
CAUTION
The Rogowski Coil has a structural life. The duration of use of the coil
depends on the use environment and use conditions.
We recommend that you replace a deformed coil or a coil with its surface
damaged, in order to maintain safety and accurate measurement. Contact
Iwatsu office or our sales distributors for replacement.
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・ Avoid the generation of corona discharge in
an environment where high voltage is
applied to the sensor for a long time.
Depending on the frequency of the applied voltage
and installation conditions of the sensor, Corona
discharge may be generated even when a voltage
lower than the resisting voltage is applied to the
sensor. This generation may lead to degrading the
insulating outer sheath, causing an electrical shock,
fire, or failure.
Corona discharge tends to be generated due to
electric field concentration. Take some measures to
avoid the generation; for example, keep the sensor
away from high-voltage parts as far as possible to
achieve insulation.
・
Stop using the Rogowski Coil with its sheath
damaged, because the resisting voltage for
insulation of the coil cannot be guaranteed.