Megger NIM 1000, Руководство пользователя

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Operation
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4.2.1 Network Impedance Measurement
4.2.1.1 Prepare Measurement
By selecting the menu item in the main menu you will reach a sub menu in which
you may select the following measurement parameters in preparation for a network
impedance measurement.
Menu
item Description
Maximum measuring current (80 ... 1000 A)
Because the accuracy of the measurement increases with increasing
measuring current, as high as possible a measuring current but also one which
is appropriate to the capacity of the network should be selected.
If the NIM 1000 is connected to a mains socket (with fusing of up to
16 A), the 80 A setting which has been particularly dimensioned for
this type of application should be selected!
Total measurement duration (0 … 20 days) and interval of the individual
measurements.
Over the whole measurement duration, one measurement per involved phase
is taken at the set interval.
After the menu item is selected, the two values are to be defined one after
another. The options for setting the interval depend on the previously set total
measurement time.
The number of measurements can also be defined as an alternative to
measurement duration (see below). The respective last adopted setting
applies.
Number of measurements (1 … 255)
The set number of measurements is carried out in quick succession and while
constantly switching between the phases involved.
The measurement duration can also be defined as an alternative to the
number of measurements (see above). The respective last adopted setting
applies.
Delay time (0 … 30 seconds)
The start of the measurement can be delayed by the time set here.
Resetting calibration values
If the time of calibration was quite a while ago (e.g. after a measurement which
lasted a while or in the case of temporary failure of a phase), it could be useful
to reset the calibration values.
Value to be calculated using a load calculation (see information on next page
too)
V
DIP
Voltage dip at given connection power
P
MAX
Max. connection power at given voltage dip
Off Load calculation deactivated
Setting the
measurement
parameters