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MEg 30 - portable version for LV networks...
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MEg 31 - portable version for MV networks...
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MEgA Měřicí Energetické Aparáty 1. Charakteristics PQ monitor is a multi-function measuring instrument to be used for the measure- ment and a long-term recording of up to four voltages and four currents, of active and reactive power and energy in three-phase four-conductor and five-conductor LV networks, as well as in MV and HV networks.
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PQ monitor – MEg30, MEg31, MEg32, MEg33 MEg 32 – PQ monitor in version for fixed mounting in LV networks MEg 33 – PQ monitor in version for fixed mounting in MV networks The following instruments have been designed for PQ monitors in portable version: –...
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MEgA Měřicí Energetické Aparáty the telereprogramming of their structure according to user’s requirements and/or the teleprogramming of newly developed functions. 2. Principle of measurement and of data processing, organization of the data memory The measurement of four voltages and of four currents is based on sampling them with frequency 5120 Hz.
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PQ monitor – MEg30, MEg31, MEg32, MEg33 The basic setting of ranges of the circular areas of the 2 MB memory has been chosen as follows: – recording of average RMS values of four voltages, four currents and three real and three imaginary components of the power;...
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MEgA Měřicí Energetické Aparáty – average values of the basic harmonic of voltages U1 to U4 and current I1 to I4, – values Umax95 and Umin95 of voltages U1 to U3, – values Umax and Umin (0.2 s) of voltages U1 to U3, –...
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PQ monitor – MEg30, MEg31, MEg32, MEg33 – number of ten-minute intervals in which average value of the 2 to 25 har- monic was higher than the value defined by the standard, – number of ten-minute intervals in which the THD for the 2...
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MEgA Měřicí Energetické Aparáty 3.8 Relay output The relay output is made by a change-over contact of the polarized relay and one or more of the following meanings can be assigned to it by the program: – voltage U1 to U4 outside the chosen tolerances, –...
PQ monitor – MEg30, MEg31, MEg32, MEg33 In order to save the energy of the internal battery, it is recommended to suppress the unnecessary (in this case) one-minute back-up supply of the monitor before each planned disconnection of measuring conductors from the supply voltage. This shall be done by using the notebook with the started program of the PQ monitor where the item Uspat shall be updated in menu Measuring instrument.
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MEgA Měřicí Energetické Aparáty Maximum size of the conductor being clamped: 10 mm × 20 mm Range of measurement: 0 to 1.2 I Accuracy of measurement: 0.5% I + 0.2% of the measured value at f = 50 Hz Frequency range: 40 Hz to 2 kHz 4.3 Measurement of frequency...
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PQ monitor – MEg30, MEg31, MEg32, MEg33 4.10 Reference ambient conditions Ambient temperature: 20°C ± 2°C Relative humidity: 40% to 60% Air pressure: 86 kPa to 105 kPa Without hoarfrost, bedewing, rain and sunshine 4.11 Ambient conditions Operating temperature: –20°C to +60°C...
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MEgA Měřicí Energetické Aparáty Terminals K1, K2, K3 of the change-over contact of the polarized relay Maximum DC/AC voltage: 125 V/150 V Maximum switched/permanent current: 1 A Maximum switched power: 30 W/60 VA Electric strength between the coil and the contact of the relay: 2.5 kV...
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PQ monitor – MEg30, MEg31, MEg32, MEg33 measurements and supply in single-phase LV networks we can use a LV adapter which shall be inserted into a LV mains socket. Modular banana plugs of measuring cables U1 and N of the MEg30 unit shall be connected into its safety jacks.
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MEgA Měřicí Energetické Aparáty According to the place of measurement, either safety alligator clips or grips with an integrated fuse shall be inserted onto modular banana plugs of the measuring conductors U1, U2, U3, U4, complying with the category of measurement IV. Grips with an integrated fuse shall be used for measurements in unprotected circuits.
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PQ monitor – MEg30, MEg31, MEg32, MEg33 6.1 Basic steps when installing the monitor – choice of type of current sensors – checking the agreement between the serial number of MEg30 and those of cur- rent sensors – choice of the range of current measurement –...
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MEgA Měřicí Energetické Aparáty surement shall be chosen by the user of the monitor according to the significance and properties of the place of its installation. In case of the portable version MEg30 it is recommended to check the accuracy of measurement every 2 years in average.
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PQ monitor – MEg30, MEg31, MEg32, MEg33 10. Guarantee It is not permitted to open the PQ monitor unit and its accessories during the guar- antee period. A guarantee in the length of two years since the date of sale is provided for the PQ monitor in version MEg30.
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