ZES ZIMMER LMG450, Руководство пользователя

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prCE-Harmonic measuring mode LMG450
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If the current is <5mA or <0.6% of I
trms
there is no judgement of the current. For this reason
‘------’ is displayed for the limit.
With the arrow keys or with the shuttle knob you can scroll through the list to see all
harmonics.
In the top line you see the total trms value of the signal and the frequency of the
synchronisation source.
Below the softkeys you see the result of the complete current judgement: a ‘
9‘ indicates that
all requirements of the standard are met. A ‘
8‘ indicates a fault measuring result. This result is
only the result of the actual measuring and not influenced by earlier measurements.
Please note:
If only ‘?’ appear and no ‘!’ then the result will be ‘
9‘, because this is only the short term
result, which might be correct.
6.4.4 Power
With Power you see the most important power values of the instrument. For the handling
please see the general description in chapter 5.4, ‘Display of values’
6.4.5 Long time evaluation
In this menu you see the result of the long time evaluation. This is started with Start and can be
cancelled with the Stop button. You see in the first row the order of the harmonics, followed
by the maximum measured current.
The third row shows the evaluation for fluctuating harmonics. According to the standard it is
allowed that some defined harmonics have values up to 1.5 times the limit for maximum 10%
of a 2.5 minute window. The maximum percentage out of this window is displayed here. If the
value is bigger than 10% you have a ‘!’ behind this value.
In the fourth row you see if the current harmonics have violated any point of the standard
anytime while the complete long time measuring. If you have here a ‘!’ the device under test
does not fulfil the standard!
In the last row you see if the test voltage has ever violated the harmonic limits.