Energy meters
While the terms "electricity bill" or "electricity meter" are
commonly used, meters actually measure electricity consumption ,
that is, the amount of electricity delivered over time. Households and
small consumers are billed for the consumption of active energy, while
larger consumers also for the measurement of reactive energy.
Meters - devices for measuring electricity consumption
Energy meters are diverse devices, both in terms of construction,
principle of operation and purpose. Well-known manufacturers such as
F&F, Kanlux, Orno or ELS offer them in various parameter configurations.
Counters - ways of dividing devices
All available for sale and use counters can be divided according to the
technology of execution into:
- inductive - the measurement of energy consumption is based on the
rotation of the aluminum target driven by the eddy magnetic field
produced by the coils. The meter counts the revolutions of the disc
and on this basis the energy bill is issued.
- electronic - made of semiconductor integrated circuits, under the
influence of current flow and applied voltage, they generate pulses
proportional to the amount of energy consumed. The counter counts
pulses over time.
Energy metering devices are also classified according to another
criterion - the number of phases they support. Meter manufacturers, e.g.
F&F, Kanlux, Orno or ELS , offer both single-phase meters (in
single-phase, three-wire 230V installations) and three-phase meters (in
three-phase installations, five-wire voltage 400V).
Energy meters are also distinguished according to another criterion,
which is the type of power supply. The devices are:
- direct (for small consumers, such as households) - the current
circuits of the meter are connected directly to the circuit covered
by the measurement, voltage circuits supplied from the circuit
covered by the measurement,
- semi-indirect - current circuits powered by current transformers
connected to the circuit covered by the measurement, voltage
circuits supplied by the circuit covered by the measurement.
Semi-indirect systems are most often installed in the case of
pre-meter protection higher than 63 A, when supplied with voltage of
400 V,
- intermediate meters - current circuits powered by current
transformers connected to the circuit covered by the measurement,
and voltage circuits powered by voltage transformers. They are used
with MV and HV supply.
Induction meters, although still in use, are gradually being replaced by
electronic meters - more accurate and enabling remote reading and
programming of parameters such as tariff zones or bidirectional .
Electronic meters - measurement of active and reactive energy, indication of network parameters and remote reading
Electronic energy meters offer many possibilities. In addition to
programming tariff zones, bidirectional meters enable the measurement of
both energy collected from the grid and delivered to it, therefore they
are used in the case of prosumers (suppliers of energy from photovoltaic
cells connected to the power grid). Indications of network
parameters in standard electronic meters include, among others:
- measurement of active and reactive energy (in bidirectional
meters, both imported and exported),
- phase voltages and currents (in single-phase meters on one phase, in
three-phase meters - on each phase separately),
- frequency,
- active power,
- reactive power,
- apparent power ,
- power factor ,
- harmonics.
Electronic meters - remote reading on the example of MeternetPRO
The meters are used not only for settlements with the energy supplier,
but also for settlements with tenants, monitoring consumption for energy
audit and for the purpose of its optimization. The MeternetPRO
program provided by F&F is an example of a powerful application. It
allows for remote reading of meter indications (as well as measurement
converters, input and output expansion modules, multimeters and other
measuring devices). Data exchange is carried out via LAN, RS-485 or
M-bus standard networks. The program is installed on an external server,
cooperation with the user takes place via a web application via any
browser, and in the case of a LAN - via the Internet.