Megger SMART THUMP ST16, User Manual

Page: 29 / 62

Operating Instructions
AVTMST16 Rev 1 May 2016
19
Menu item Description
>> Automatic HV
release
The way a HV test is started, automatic or manual .
Automatic means that after initializing HV by pushing the HV ON button, HV will
build up in the test mode or will charge the capacitor and fire as soon as voltage
has been reached (typically preferred in North America).
Manual means that in both situations the HV has to be manually “released”, once
the preset level has been reached (typically preferred in Europe).
Voltage
selection
When set to Manual the unit will always default to 2kV as a starting level in all HV
modes. The operator must then select the actual HV level in any operating mode
and operation menu (Quick-Steps and Expert mode).
When set to Automatic , the unit, when in Quick Steps mode only , will always
fire a shot in ARC reflection at the full voltage (max. energy) and when in thump
mode will go to maximum voltage (operator can down adjust). If a
HIPOT/Breakdown test was performed before hand, then the unit will match the
thump voltage to the breakdown voltage during the HIPOT test
plus 4kV, i.e.
breakdown 4kV, thump voltage will be set to 8kV.
Sheath Test
Limit
Units, which have the Sheath Test Option enabled, have a default test voltage that
can be adjusted between 2 and 5kV.
Continuous
Testing
1. When disabled, only DC HIPOT / breakdown tests can be performed.
2. When enabled, DC HIPOT /Proof tests can be performed for up to 30 minutes
and the data can be exported via USB stick and loaded on the EasyPROT
software.
3.
Must be enabled to perform Sheath Tests.
>> Set-up Start
Marker
Procedure to adjust the start marker position to the end of the actual length of the
HV output cable (typically on SMART-THUMP at the end of the 50ft (17m) HV out-
put cable).
The procedure is fully automatic and the operator is prompted when necessary!
First a measurement is taken with the ends of the connection cable open. Then the
gain setting is adjusted if needed and confirmed and a copy of the trace is frozen.
A second trace is recorded with the ends of the connection cable shorted to each
other, which should show a significant change. The marker is automatically placed
on the position where both traces start to split.
If required, the marker can be manually adjusted. This setting of the start marker
will be stored as the default, if operator acknowledges the prompt,
and should
only be changed if the length of the connection cable is changed.
Cable List
By means of the cable list the appropriate propagation velocity can be quickly
adjusted / selected by identifying the type of cable to be tested
Cable list can be exported and imported which allows for example to edit an
exported list (XML file) according to the preferences of the customer (see page
43) and then share it among all units of a customer
This submenu offers the following options:
Set default Menu item to select the default cable list out of all available cable
lists. Only the cable types of the default cable list can be accessed
during measurement.