Megger IDAX 300, Руководство пользователя

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AG033586EE ZP-AG03E IDAX 300/322/350 21
4 IDAX 5 SOFTWARE
Now you have a “File” with one “Test”, the CHL
configuration, visible on the legend in the left-hand
side of the main window (see picture below). On the
top you have several “Tabs” showing Nameplate, The
Test (Named Moisture), Hook-up, Graph (and table),
Settings and Help.
7]
Press the “Hook-up” tab to show the cable
connections from the instrument to the
object.
There are two pictures showing the two versions of
IDAX 300, IDAX 300 delivered 2011 or earlier (to the
left) and IDAX 300 delivered 2012 or later.
Note If you have an older IDAX 300 with two input
connector for each channel, the SENSE input
must NOT be connected
8]
Ensure that the safety ground cable is
connected to the IDAX 300 instrument and
to the station ground near the test object/
transformer. This cable acts as safety ground
AND test input lead.
9]
Make sure that all HV phase terminals and
any exposed neutral terminal are connected
together. While connecting together the
terminals with bare copper wire, the phases/
windings should be connected to ground.
10]
Make sure that all LV phase terminals and
any exposed neutral terminal are connected
together. While connecting together the
terminals with bare copper wire, the phases/
windings should be connected to ground.
11]
Connect the Generator cable to the high
voltage winding – according to the picture in
Hook-up tab
.
12]
Connect the Red input lead to the low
voltage winding – according to according to
the picture in Hook-up tab.
13]
Remove any grounding connection from the
windings before you start the measurement.
14]
Connect to the IDAX instrument using the
“Connect” button located on the right-hand
side of the main window or simply press the
“Start” button (that will connect to IDAX 300
if not connected yet).
15]
Press “Start” to initiate the measurement/test
Measurement
The Moisture Test will start a routine initiation
procedure where the system measures all
1)
capacitances, including stray capacitances in the
test object as well as the interference level. This
routine procedure sets up the instrument and the
model ensures the highest possible accuracy over the
selected frequency range.
Note
A capacitance check is also performed and
in case the measured capacitance to ground
does not match with the sum of individually
measured capacitances, the measurement will
be stopped. If so, re-check that all connec-
tions are correct and start the measurement
again.
Note
From 2012, IDAX has single input terminals
and utilizing a new methodology where stray
capacitance are estimated and compensated
for based on pre-measurements on all termi-
nals, red, blue and ground. In previous IDAX
models with dual input terminals, “input” and
“sense”, some stray capacitances were not
compensated for.
Note: The compensation is only important for
higher frequencies well above 50/60 Hz.
Next, the Dielectric Frequency Response (DFR)
measurement starts from the highest selected
frequency (usually 1000 Hz) and then steps down
to the set “Stop frequency” of e.g. 1 mHz. After
measuring 40 Hz, power frequency capacitance and
dissipation factor are calculated and presented.