Megger SMART THUMP ST16, User Manual

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M
AVTMST16 Rev 1 May 2016
14
Connection Diagram
The following figure shows the simplified connection diagram.
Connection Sequence
Connect the unit in the following order:
Step Description
Connect the safety ground lead to a reliable ground (e.g. station-ground,
transformer ground rod. Do not drive a separate ground rod!).
Connect the HV return lead to the cable shield or the concentric neutral of the
specific cable to be tested. The resistance between the HV return (operational
ground) and the safety ground should be less than 5
Ω
(check with ohmmeter, if
questionable), if not the F-OHM safety feature will be activated, disabling the HV
ON function or activating the HV OFF function.
NOTE: The closer and better the HV return is connected to the
shield / concentric of the cable to be tested, the better the
TDR trace readings will be.
Connect the HV lead to the phase conductor to be tested (optional elbow
adapter or vice-grip. (See 'Available Accessories' in Section 2).
Connect the supplied power cord to the connector on the back of the unit
and connect the other end to a power outlet.
NOTE: If no power connection can be established, the unit can be
operated from the internal battery, provided it is equipped
with this feature and is properly charged. The unit also
provides 2 battery terminals that are accessible from the
out-side, which can be connected to an external battery
Only after all necessary connections have been made, the ground connection
to the cable under test can be lifted.
110 V … 230 V
±15%,
50 / 60 Hz