One-shot Results for Narrowband, Full Spectrum and Harmonics
|Memory and Interfaces||
|LMG640 (Table top)||455 mm||224 mm||200 mm|
|Weight||Depending on installed options: max. 7.2 kg|
|Protection class||EN 61010 (IEC 61010, VDE 0411), protection class I / IP20 in accordance with EN 60529|
|Electromagnetic compatibility||EN 61326|
|Temperature||0 ... 40 °C (operation) / -20 ... 50 °C (storage)|
|Climatic category||Normal environmental conditions according to EN 61010|
|Line input||100 ... 230 V, 47 ... 63 Hz, max. 200 W|
In the wake of stricter monitoring of consumption and efficiency of electrical appliances, new standards and procedures (eg SPECpower_ssj2008, IEC 62301) will continuously be created to enable an objective comparison of the different manufacturers. Whether it is workstations, servers or appliances, is irrelevant to the principle: The long-term evaluation of the power consumption has always to take all relevant operating conditions into account. The differences between minimum load - e.g., Idle mode, - and full load can thereby be of considerable magnitude, which requires a very sophisticated means of measurement (see also Application Note No. 102, "Measurement of standby power and energy efficiency."). The measurements must be carried out over several hours and may not show any gaps. By selecting a sufficiently large measurement range, range changes and the inevitably resulting data losses can be avoided. The fundamental precision LMG600 also ensures an accurate measurement at the lower limit of a range.
The fast switching semiconductors used to improve the efficiency of
modern frequency converters cause extremely steep voltage edges. The
resulting capacitive currents affect the bearings and the motor
insulation - this can lead to premature failure.
Motor filter (e.g. du / dt filter) attenuate the voltage gradient, but generate themselves power dissipation due to the settling of the filters' frequencies (typically > 100 kHz). The high bandwidth and the small time difference between the current and voltage of the LMG600 enable highly accurate power loss measurements on the filters at these frequencies, and longitudinal measurements with small cos φ. This also applies to power measurements at high bandwidths up to 10 MHz. This requires that the current and voltage channels must be designed for minimum delay differences; in the LMG600 it is less than 3 ns; this corresponds to 50 Hz at an angle error <1 μrad. The instrument is therefore ideally suited for the power loss measurement at small phase angles for transformers, inductors, capacitors and ultrasonic sensors. No options or adjustments are necessary, as the devices will fully meet this measurement task already in the default setting when shipped. For measurements on circuits of highest performance, typically current and voltage transducers are employed. The phase angle of the converter can be corrected via the runtime menu and thus the measurement accuracy can be improved.
Particularly in the aerospace industry, electromagnetic compatibility between installed systems poses an existential threat. For this reason, applicable legislation such as ABD0100.1.8 sets limits on harmonic currents up to the range of 150 kHz. These harmonics can be analyzed using the LMG670. First of all, this is possible directly thanks to the implementation of harmonics analysis, and secondly it allows for the desired level of detail through the transfer and analysis of the sampling values using external software.