English
Electrical energy or the grid current is metered for various reasons:
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consumption of various technologies (heat pumps, heating water, etc.)
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monitoring maximum power (not to exceed max. current of the circuit breaker)
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regulation of the PVPS internal consumption
In the following examples we consider secondary measurement (not for billing). The electricity meter at the entrance to the building (a property of the distribution companies) is equipped with a communication interface, but it is sealed and we do not consider using it.
We have a 4-quadrant fast electricity meter C-EM-0401M available directly on the CIB bus. We are currently preparing a simpler version of the CIB three-phase electricity meter C-EM-0300M and its wireless version R-EM-0300M-A.
We have solutions with EMU and EMI modules for measuring consumption (and production) and other quantities for a large number of outlets.
Metering the consumption of 1ph devices (the heat pump compressor) and calculating the instantaneous current (for visual information and easier control according to the current - load isolating, etc.); it is recommended to use a 1ph electricity meter with a pulse output 9901M, or ED11.M.
In metering the consumption of 1ph devices, you can also use the ED 110 electricity meter with an optical interface; the values (power, voltage, current) are read by the TXN 149 01 optical head; the electricity meter is a two-tariff device, so the power is read separately for each tariff. The pulse output S0 can also be used in the ED 110 electricity meter.
In metering the generation and consumption of 1ph electrical energy (photovoltaic power plants, the wind power station for the owner's own consumption, etc.), you can use the ED 110 electricity meter with an optical interface, and the values (the power of consumption and supplies for two tariffs, voltage, current), are read by the TXN 149 01 optical head.
Metering the consumption of 3ph devices (in the household) and calculating the instantaneous current (for visual information and easier control according to the current - load isolating, etc.) can utilize the 9901M 1ph electricity meter for each phase separately; a disadvantage is the need for three pulse inputs, and an advantage is the availability of information about each phase and a good price.
Metering the consumption of 3ph devices can also be done by the three-phase electricity meter with an S0 pulse output, the ED 310 type (for currents up to 63 A with direct measurement, for higher currents there is the 310I ED variant with indirect measurement); only one pulse input is needed, but there is no separate information about the consumption of each phase; or the optical interface can be used, and the values (power, voltage, current) are read by the TXN 149 01 optical head; the electricity meter is usually at least for two tariffs (the ED 310 can manage up to four tariiffs), so the power for each tariff can be read separately. The RS485 communication interface or the M-bus can also be used for communication.
Metering the generation and consumption of 3ph power (PVPS, wind power for the user's own consumption, etc.) can be done by the ED 310 three-phase electricity meter with direct measurement (for currents up to 63 A), or the ED 310I with indirect measurement (for higher currents); an optical interface is used, and the values (power consumption and generation, the voltage, the current), are read by the TXN 149 01 optical head; the electricity meter ED 310 is for up to four tariffs, so the power for each tariff can be read separately. Alternatively, the RS-485 interface or the M-bus can be used for communication.
Detailed measurement of 3ph network can be done by the SMM33 module, which is designed to measure and monitor line and phase voltages, currents, active and reactive power, the power factor, THD voltages and currents and frequencies in single-phase and three-phase low voltage networks.
Metering the supply and consumption of DC electrical energy (MVE, PVPS) can be done by the DC meter VMU-E, which allows measuring voltages up to 400 VDC and currents up to 1,000 ADC. The electricity meter is connected to the RS-485 interface of the Foxtrot basic module via the VMU-X communication module.