The multi-purpose electric meter СЭТ 4ТМ is installed for multi-tariff electricity metering in 3 and 4-wire power grids AC voltage with a frequency of 55 ± 2 Hz, with a rated current of 1-5 Amps with transformer connection current and direct connection to stress.
Electric meters SET 4TM produce: accounting and measurement of reactive and active electricity (taking into account losses), the fixation of power peaks, maintaining power current arrays with a programmable integration indication, measurement of the power quality indicator and indicators three-phase network.
Metering devices SET 4TM 03M, SET 4TM02M can be installed as a means industrial or commercial accounting electricity in small-motor and household areas, in industrial enterprises and in energy systems that account for intersystem flows and power grids of power flows.
The metering of electricity metering СЭТ 4ТМ 03М has 3 communication interfaces, and СЭТ 4ТМ02М - 2, and can work both separately and and as a part of the dispatcher control automation systems and in the system of automated metering and control of electricity.
- 1 Counter Types
- 2 Safety regulations
3 Principle of operation and function
- 3.1 Energy accounting and tariffing
- 3.2 Power load profiles
- 3.3 Determination of load maxima
- 3.4 Measurement of energy quality and electrical parameters
- 3.5 Digital inputs and test outputs
- 3.6 Indication
- 3.7 Communication interfaces
- 4 Design
- 5 Operating rules
The power meter is connected to the network using current and voltage transformers. Electric meter with a voltage of 3x (57.8-115) / (150-250) volts can be used on connections with phase voltages from the range of 57.8-125 volts. Set 4m 03m meter with 3x (130-240) / (209-410) volt voltage can be used as transformers for measuring voltage and without them at connections with phase voltages out of the range: 120-230 volts.
The model range of electricity meters includes meters that differ in the level and accuracy, rated currents, rated voltages, availability of a backup power source, and availability of communication interfaces. Electricity meters SET 4ТМ02М and СЭТ 4ТМ 03М differ only in the number of means of communication. At SET 4ТМ02М there is an optical port and one RS485 interface, for SET 4ТМ 03М there is an optical port and 2 RS485 interfaces. All interfaces are isolated, equal priority and independent.
Bidirectional electric meters set 4tm 03m can rebuild for work in unidirectional mode and record:
- reactive energy of the 2nd and 4th quadrants, as reactive energy of the 4th quadrant (capacity load) and backward-directed reactive energy;
- reactive energy of the 5th and 3rd quadrants, as reactive energy of the 3rd quadrant (induction load) and direct-directed reactive energy;
- active reverse and direct directional energy, as direct directional active energy (metering independent of current movement in a separate phase of the power grid).
The operation of the meter in the unidirectional mode is allowed only on lines with unidirectional current flow. Moreover, the possibility of data distortion with incorrect connection of the instrument current circuits is excluded.
Before you begin work, you need to carefully study the instructions for the electric meter set 4m 03m. Repair, maintenance and installation of the meter is performed by an accredited service company. Only persons who have been instructed in safety with an electrical safety group of at least III and with a tolerance of up to 1000 volts of voltage are allowed to work on installing the meter.
All work with the meter must be carried out when the power is disconnected.
Principle of operation and function
Energy accounting and tariffing
Counter set 4tm 03m produces a multi-tariff record of reactive and active energy of the reverse and forward direction and 4 quadrant reactive energy in 8 zones of the tariff, on 8 types of days (Monday-Sunday / holiday) in 12 months.
The tariff zone discrete is 10 minutes.. The sequence of tariff zones in days is limited by the number of 10-minute intervals in days and has 144 cycles.
The electric meter tariff set 4m 03m uses the list of transferred days and the schedule of holidays. Due to the list of postponed days, you can change the tariffs by day type, without changing the tariff schedules (for example, working Sunday, which should be charged as Monday).
The meter produces non-tariff energy metering, taking into account the reactive and active losses in the power transformer and power lines.
The meter saves the archives of the recorded tariff electricity and non-tariff electricityconsidering losses (4 quadrant reactive, reactive reverse and forward direction and active electricity):
- for the previous and current days;
- all from the reset;
- for all previous days with archiving up to 30 days;
- over the past year and the beginning of this year;
- for the past day and at the beginning of this day;
- in the past 12 months and this month;
- at the beginning of each past calendar day with archiving up to 30 days;
- for the past and current year;
- for the past 12 months and at the beginning of this month.
At the same time, the set 4m 03m counter can be rearranged to a single tariff mode, regardless of the set tariff schedule. In this case, accounting is done according to the tariff number one.
Power load profiles
The electric meter performs maintenance of three 4-channel independent power profiles with a set integration time of 2-60 minutes for reactive and active power in reverse and forward direction. If the meters are used on connections with voltages of 3x (150-125 / 173-250) Volts, the integration time is set only in the range of 2-30 minutes.
Any power profile array can be configured to take into account the power load profile, taking into account reactive and active losses in the power transformer and power lines with programming time 2-30 minutes
Determination of load maxima
The meter can operate as a recorder of power maxima (reactive, active, inverse and direct directions) for any individual array of profile power using the 12-month schedule of evening and morning maxima.
Power peaks stored in the archives of the electric meter:
- for the past and each of the past 12 months;
- from reset (reset by interface request or manual reset).
The archives of the maxima preserve the peak value and the time, which corresponds to the completion of the power integration interval of a certain profile array.
Measurement of energy quality and electrical parameters
The meter makes instant measurement (cycle time 0.3-5 seconds) physical indicators that distinguish the three-phase grid, and can be used as a parameter meter.
The meter can be used as a device measuring the quality of electrical energy indicators of steady-state frequency deviation of the network and phase (direct sequence, interphase) stresses.
Digital inputs and test outputs
The counter is equipped 4 test isolated exits main transmitting device, each can be configured separately:
- to create a fixed signal indicating the excess of a given power threshold (reactive, active, reverse and forward);
- to create telemetry pulses of a specific electric power metering channel (reactive, active, 4 quadrant reactive and reverse and forward, as well as taking into account losses)
- to check the accuracy of the clock;
- to create telecontrol signals.
There are electric meters 2 digital inputsthat are programmed:
- for the entrance of the telealarm system;
- in order to count the number of pulses that come from external connections (on both fronts, the trailing or the leading edge);
- in order to control the test mode A or B.
The meter is equipped with a liquid crystal indicator for the measured values or the indication of the recorded energy, and three keys to switch the image modes.
Electric meter in the display mode of the main indicators can display on screen:
- the number of pulses from outdoor devices on a digital input;
- electricity, taking into account losses in the power transformer and transmission lines;
- counted reactive and active electric energy of reverse and forward direction and 4-quadrant reactive electric energy in the sum of tariffs and for each tariff.
All the above data is stored in archives with the ability to view on the screen:
- for the past and current year;
- all from the discharge of evidence;
- for the past and the current day;
- for the past and current month.
The meter in the display mode of the main indicators, in addition to the above, shows the fixation time and values evening and morning power maxima 1 and 2 profile power array.
The meter in the mode of indication of additional indicators can display the data of additional measurement modes on the screen.
The electric meter СЭТ 4ТМ02М is equipped with two galvanically isolated, independent, equal priority communication interfaces: optical interface and RS485.
SET 4TM 03M is equipped with three galvanically isolated, independent, equal priority communication interfaces: optical interface and RS485.
To work with the electric meter through communication interfaces, the software "Configurator SET4TM" is used.
The meter can support the SET 4ТМ02-compatible, Mod Bus-like protocol and gives the ability to perceive through the communication interfaces measured parameters and historical data, reprogram, program and read data:
The meter provides the ability to manage using the communication interface:
- display modes;
- synchronization, correction and time setting;
- resetting highs;
- initialization of the meter.
- reset testimony;
- search for the address of the profile array header;
- initialization of power profile arrays;
- restarting the meter;
- data storage of additional measurement modes.
Access to data and parameters from the interface has password protection for programming and reading. Factory settings and metrological coefficients are protected by a mechanical jumper and are available only after opening the seals.
The design of the electric meter satisfies the documentation of the manufacturing plant and the standards of GOST.
Structurally, the device has the following nodes:
- protective cap of the contact block;
- network filter card;
- contact block;
- control board;
- board backup power unit.
The body is made of high-strength polystyrene and includes a top and base.
In the category of impact factors of mechanical loads and the environment meter refers to the fourth group according to GOST-22261 94, and can be operated at air temperatures from -40 to + 60C, air humidity up to 90% and pressure of 80-106.8 kPa.
Electric meter for mechanical and climatic influences in terms of limiting conditions of transportation meets all requirements for electrical measuring instruments of group 4, with air temperature from -40 up to + 70С. The meter is installed in enclosed spaces. Its body in terms of protection against the ingress of foreign objects and moisture correspond to the group IP 51.