1.1.1 OPERATION MODE ‐ CONSTRUCTION: Meter shall be electronic (static) for single‐ phase two‐wire direct connection.
1.1.2 RATED (REFERENCE) VOLTAGE: 230 V (‐20%, +15%).
1.1.3 RATED CURRENT: 5 (≥ 60) А.
1.1.4 RATED FREQUENCY: 50 Hz.
1.1.5 AUXILIARY CONSUMPTION OF THE METER:
Auxiliary mean power of voltage circuit under reference voltage, reference temperature of 23°C and reference frequency shall not exceed the value of 5 W and 25 VA (SRPS EN
62053‐61 standard).
Auxiliary consumption of the meter current circuit under basic current, reference frequency and reference temperature of 23°C shall not exceed the value of 2.5 VA for the meters of class 2, i.e. 4 VA for the meter of class 1 (SRPS EN 62053‐61 standard).
1.1.6 MINIMUM ACCURACY CLASS:
For active energy and power
SRPS EN 62053‐21 standard 2
EN 50470‐3 standard A
1.1.7 ANTICIPATED OPERATION LIFE: minimum 15 years.
1.1.8 SIZE (HOUSING, TERMINAL AND COVERS):
Dimensions (main measures) have to be done according to Figure 1. All measures are given in mm.
b1 b2 C h1 h2 h3 h4
Figure 1 Meter draft of principle
Dimension h4 has to fulfil indicated condition for all conductor introductions, regardless of the shape of the cover and it is measured from the lowest part of the terminal (end of the switching module when it is installed) to lower part of its cover vertically below the conductor introductions on terminal.
1.1.9 Terminal
In terminal, Meter lines for direct connection are coupled with clamps with copper rail and one or two screws, or capsular clamps according to the standard SRPS EN 62052 – 11.
Auxiliary and control terminals are executed under the ‘PLUG IN’ principle or through corresponding clamps.
Terminal is executed, in such a way, to fully eliminate the possibility of winding sliding (maximum moment of re‐screwing the screws defined by the manufacturer), screw fallout from ‘sockets’ and simultaneously providing easy re‐screwing of screws and safe ‘opening’ of clamps in accordance with the opening size for conductor introduction into the terminal, regardless of meter position.
Each clamp screw shall have the size and corresponding travel to fully and reliably fasten the conductor and secure reliable and secure mechanical and electrical connection of current rail with the conductor, without additional interventions on the conductor (bending, cross‐section increase, etc.).
1.1.10 DISPLAY
Metered values and characteristic codes are represented on LC display. Presentation of metered values and characteristic codes shall be easily readable even in badly lit environment, as well as under direct lighting.
Display may be executed as segment, “dot matrix” and other, when the data presentation is provided in accordance with the request.
LC display operates in automatic, manual and self‐check display regime. Transition between automatic and manual display operation regime is executed in a simple manner, e.g. by pressing the key/keys. Default display regime is automatic, to which the display returns from manual display after corresponding idle period (keys are not pressed), which is programmable. Under automatic regime, values of metered and registered values are shown cyclically. Individual value display period should be programmable and between 5 to 20 sec. Values presented on LC display, their sequence and number shall be changeable (programmable). Initially, only accounting elements and current date and time are cyclically changed in the period of 5 sec on meter display.
Under manual display regime (value display regime based on selection), access should be enabled to the standard data menu (accounting data, current power, voltages, currents, etc.). Values displayed in the standard data menu, their sequence and number shall be changeable (programmable) and independent from the setting for automatic display regime.
Self‐check display regime is realised to visually verify the accuracy of symbol and character display on it (verification of proper operation of all LC display elements), as well as basic meter functions. Self‐check function is described in more detail under point 2.6.
If display elements are blinking, this shall have the frequency of about 1 Hz.
Presentation of metered values covers minimum 8 (eight) digits, while there is minimum 6 (six) whole digits, and minimum 2(two) decimal digits.
Display of maximum power (maxigraph) has minimum 8 (eight) digits, while at least 2 (two) digits are used for display of decimal digits, and the remaining for whole digits.
5 (five) to 7 (seven) digits are anticipated for display of characteristic codes.
Display of metered values and characteristic codes shall be clearly separated from one another. Characteristic codes are in accordance with SRPS EN 62056‐61 (OBIS).
Figures for value display shall at least be:
For metered values 7 mm
For characteristic codes 5 mm
In case of wrong energy flow direction detection, phase presence display symbol shall blink with the frequency of about 1 Hz.
L
In case of detection of metering integrity violation (terminal cover opening, meter housing opening, parameter change, strong magnetic field impact on the meter, etc.) it is desirable that the signalling for violation is performed via display with all elements blinking, until status registry is reset.
General appearance of the display with the display sequence is as shown on Figure 2 and together with the scrolling function is in accordance with VDN recommendations, by which the position of the elements is not critical.
Area of metered values
Phase display Unit display
Area of characteristic codes Cursor field
Figure 2 Principal general appearance of display
Access to accounting elements for previous months is realised in a very simple manner (e.g. by pressing the key for 2 sec), grouping the values according to accounting period, chronologically, starting from the last accounting period towards previous ones.
1.1.11 KEYS
Meter has at least one easily accessible key for menu scrolling. Keys enable menu scrolling functions, selection of desired menu, return to the previous menu level, return to automatic operation regime, as well as reconnection of bistable switch under meter operation regime ‘conditional switch reclosing’.
1.1.12 Number Of Tariffs
Meter has the possibility of storing metered values in 4 (four) tariff registers.
1.1.13 Impulse (Test) Terminals
Meter has at least two impulse terminals. One shall be optical (via red LE diode), the other electrical, with galvanic insulation, passive and executed on a corresponding terminal connection.
1.1.14 Characteristics of Impulse Terminals
Characteristics of impulse terminals of the meter are realised according to the standard SRPS
EN 62053 – 31 i.e. SRPS EN 62052 – 11.
1.1.15 Meter Constant
Meter constant is expressed by the number of impulses per energy unit (imp/kWh), amounting to:
Electrical – 500 imp/KWh
Optical – 1000 imp/KWh
1.1.16 Temperature Range and Climatic Conditions
Meter functions under the standard temperature range for climatic area in which JP EPS customers are located.
Operating temperature is within the range from – 25°C to + 55°C.
Meter functions under the conditions of relative humidity from 95% in the period of 24 hours.