Megger SG32-1500M, Руководство пользователя

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SG32-UG-EN-V01 Dec 2016
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GETTING TO KNOW YOUR SG32-1500M
Basic Operating Principle of User Interface
All Controls
The built-in controller (PLC) ensures that all operational steps must be executed
in a logical sequence, which provides the highest level of safety to the operator
when working with this type of HV equipment.
The guiding principle for
operation of the SG32-1500M is to always push the lit button to go to the
next step.
Overview of Methods available on the SG32-1500M
TDR / Pulse Reflection
TDR or Pulse Echo is a low voltage method of fault pre-location suitable for
locating short and open circuits and other faults below about 300Ohm. It is not
suitable for high impedance or flashing faults, where HV method should be
used.
Arc Reflection
Arc Reflection is the most widely HV method of fault Pre-location used, especially
on solid dielectric insulated MV and HV cables. It is suitable for high resistance,
flashing and other faults that can be ignited by a surge generator. A reference
trace is taken without the arc, and then a real-time trace is taken during the arc
and recorded and compared to the reference trace. The point of divergence
(impedance change) is the fault position.
Arc Reflection (Multi-shot)
Arc Reflection Multi-shot defines a technique with multiple TDR pulses fired during
the HV phase. It allows finding the optimal trigger point without having to
adjust the optimum trigger delay. It provides the advantage of being able to view
multiple traces, all of which have been captured during the period of the arc at
different times. It's an excellent feature for hard to flash over / capture faults,
e.g. in PILC cables.