Iskra WM3M4 User manual

User’s Manual
1
Three-phase electrical energy meters for
charging stations
WM3M4 & WM3M4C
October 2020 • Version 1.07

THREE-PHASE ELECTRICAL ENERGY METERS FOR CHARGING STATIONS
ii
User’s Manual WM3M4 &WM3M4C
Three-phase electrical energy meters for charging
stations
WM3M4 & WM3M4C
User and Installation manual

SECURITY ADVICES AND WARNINGS
User’s Manual WM3M4 &WM3M4C
iii
Security Advices and Warnings
Please read this chapter carefully and examine the equipment carefully for potential damages which might
arise during transport and to become familiar with it before continue to install, energize and work with
the WM3M4 & WM3M4C three-phase energy meters.
This chapter deals with important information and warnings that should be considered for safe installation
and handling with a device in order to assure its correct use and continuous operation.
Everyone using the product should become familiar with the contents of chapter »Security Advices and
Warnings«.
If equipment is used in a manner not specified by the manufacturer, the protection provided by the
equipment may be impaired.
PLEASE NOTE
This booklet contains instructions for installation and use of a three-phase energy meters
WM3M4 & WM3M4C. Installation and use of a device also includes handling with dangerous
currents and voltages therefore should be installed, operated, serviced and maintained by
qualified personnel only. ISKRA Company assumes no responsibility in connection with
installation and use of the product. If there is any doubt regarding installation and use of the
system in which the device is used for measuring or supervision, please contact a person who is
responsible for installation of such system.
Before installing
Check the following before installing:
Nominal voltage.
Terminals integrity.
Protection fuse for voltage inputs (recommended maximum external fuse size is 40 A).
External switch or circuit breaker must be included in the installation for disconnection of the
devices’ power supply. It must be suitably located and properly marked for reliable
disconnection of the device when needed.
Proper connection of communication terminals.

USED SYMBOLS ON DEVICES’HOUSING AND LABELS
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User’s Manual WM3M4 &WM3M4C
Used symbols on devices’ housing
and labels
SYMBOL
EXPLANATION
DANGER
Indicates proximity of hazardous high voltage, which might result in serious injury or
death if not handled with care.
WARNING
Indicates situations where careful reading of this manual is required and following
requested steps to avoid potential injury is advised.
Compliance of the product with directive 2002/96/EC, as first priority, the prevention
of waste electrical and electronic equipment (WEEE), and in addition, the reuse,
recycling and other forms of recovery of such wastes so as to reduce the disposal of
waste. It also seeks to improve the environmental performance of all operators
involved in the life cycle of electrical and electronic equipment.
Compliance of the product with European CE directives.
Disposal
It is strongly recommended that electrical and electronic equipment (WEEE) is not deposit as
municipal waste. The manufacturer or provider shall take waste electrical and electronic equipment
free of charge. The complete procedure after lifetime should comply with the Directive 2002/96/EC
about restriction on the use of certain hazardous substances in electrical and electronic equipment.

User’s Manual
v
Table of contents
1BASIC DESCRIPTION AND OPERATION 1
1.1 DESCRIPTION OF THE DEVICE 2
1.2 HARDWARE DESCRIPTION 3
1.3 MAIN FEATURES 3
2CONNECTION 4
2.1 MOUNTING 5
2.2 ELECTRICAL CONNECTION 6
3FIRST STEPS 8
3.1 DISPLAY OF DEVICE INFO 9
3.2 WELCOME SCREENS 9
3.3 LCD DISPLAY INFORMATION 10
4SETTINGS 13
4.1 INTRODUCTION 14
4.2 MIQEN SOFTWARE 14
4.3 CONNECTION 15
4.4 SETTINGS 17
4.5 MEASUREMENTS 23
5MEASUREMENTS 25
5.1 ONLINE MEASUREMENTS 26
5.2 SELECTION OF AVAILABLE QUANTITIES 27
5.3 CALCULATION AND DISPLAY OF MEASUREMENTS 28

TABLE OF CONTENTS
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User’s Manual WM3M4 &WM3M4C
6DIGITAL SIGNATURE (VALID ONLY FOR WM3M4C) 30
6.1 INTRODUCTION 31
6.2 DIGITAL SIGNING PROCEDURE 31
6.3 ENERGY METER CRYPTOGRAPHIC FUNCTIONS EXPLANATION 32
6.4 CONSUMPTION MEASURING AND DIGITAL SIGNING PROCEDURE 33
6.5 CRYPTO REGISTER DEFINITIONS 33
6.6 POWER LOSS BEHAVIOUR 43
6.7 UNEXPECTED RESET BEHAVIOUR 43
7TECHNICAL DATA 44
7.1 ACCURACY 45
7.2 MECHANICAL CHARACTERISTICS OF INPUT 45
7.3 ELECTRICAL CHARACTERISTICS OF INPUT 46
7.4 SAFETY AND AMBIENT CONDITIONS 47
7.5 EU DIRECTIVES CONFORMITY 48
7.6 DIMENSIONS 49
8ABBREVIATION/GLOSSARY 50

BASIC DESCRIPTION AND OPERATION
User’s Manual WM3M4 &WM3M4C
1
1BASIC DESCRIPTION AND OPERATION
The following chapter presents basic information about WM3M4 & WM3M4C three-phase energy
meters required to understand its purpose, applicability and basic features connected to its operation.
In this chapter you will find:
1.1 Description of the device 2
1.2 Hardware description 3
1.3 Main features 3

BASIC DESCRIPTION AND OPERATION
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User’s Manual WM3M4 &WM3M4C
1.1 Description of the device
1.1.1 Functionality of WM3M4 & WM3M4C
The WM3M4 & WM3M4C energy meters are MID certified meters, intended for energy
measurements in the three-phase and single-phase electrical charger stations. The WM3M4C energy
meter features high temperature operation and digital signing for a charging event, whereas WM3M4
features only high temperature operation. Both meters measure energy directly in 4-wire networks
according to the principle of fast sampling of voltage and current signals. A built-in microprocessor
calculates power, energy, current, voltage, power factor, power angle, frequency, harmonics of THD
voltage and THD current harmonics. WM3M4C meter can detect and log events relevant for charging
via RS485 communication. Thus the meter can produce relevant digital signature for charging event.
1.1.2 Appearance
1. RS485 terminals
2. Current terminals –to load
3. LCD display
4. IR COMM PORT –on side
5. QR code (valid only for WM3M4C)
6. DIN-Rail fitting
7. LED indicator (1000 imp/kWh)
8. Current terminal –source (max 40 A)
LCD
Number of digits: 8 (6+2)
Height of digits: 6.52 mm
LED
Colour: red
Pulse rate: 1000 imp/kWh
LED on: no load indication
Figure 1: Appearance of a three-phase electrical energy meter WM3M4C
The energy meters have a built-in optical (IR) communication port on the side as a standard. A special
WM-USB adapter (size 1 DIN module) can easily be attached to it. It can be used for direct
communication with a PC to change settings of devices without any communication installed.
On the housing there are two terminals, A(16) and B(15) for RS485 communication.
Terminals can be sealed with a protective cover to prevent unauthorized access. They are fixed in
accordance with EN 60715.

BASIC DESCRIPTION AND OPERATION
User’s Manual WM3M4 &WM3M4C
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1.2 Hardware description
The whole system of the WM3M4 & WM3M4C energy meters is equipped with the following units:
Stand-alone unit.
Power supply unit.
Process unit (MCU microcontroller) with IR communication, LED display, LCD support, and
EEPROM.
Additional unit for RS485 communication.
Communication:
Every meter is equipped with IR optical communication and RS485 communication. Both
use the MODBUS protocol. It is used for setting and reading a meter with the WM-USB
adapter or RS485 adapter. The WM3M4 & WM3M4C energy meters can also be connected
to SG (smart gateway). It is intended to connect various equipment into the communication
network.
The LED shows the state of active energy. It flashes in proportion to the received active
energy. When there is no load, the LED lights up.
1.3 Main features
3 DIN modules width three-phase direct connected DIN-rail mounting meter.
Class 1 for active energy according to EN 62053-21.
MID approval WM3M4 & WM3M4C for class B according to EN 50470-3.
Reference frequency 50 Hz or 60 Hz.
Maximum current (Imax) 40 A
Basic current 5 A (Ib)
Reference voltage 3x230 V/400 V ().
Voltage operating range (-20 % ... +15 %).
Two row display 6+2 digit (10 Wh resolution) with backlight.
Multifunctional front LED.
IR Serial communication.
RS485 Serial communication.
Measurement of
oPower (active/reactive/apparent for each phase and total)
oEnergy (active - bidirectional).
oVoltage (each phase).
oCurrent (each phase).
oPhase to phase voltage.
oPhase to phase angle.
oFrequency.
oPower factor (each phase and total).
oPower angle (each phase and total).
oTHD of voltage.
oTHD of current.
Crypto engine (Hash, signature) for generation of secure datasets (valid only for WM3M4C).
Possibility to connect as a single phase (on L3).
Remote control for backlight LCD.
Secure data transfer (digital signature) (valid only for WM3M4C).
70°Cambient operation temperature.
Sealable terminal cover.

CONNECTION
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User’s Manual WM3M4 &WM3M4C
2CONNECTION
This chapter deals with the instructions for connection of the WM3M4 & WM3M4C energy meters.
Both the use and connection of the device include handling with dangerous currents and voltages. The
connection shall thus be performed ONLY by a qualified person using appropriate equipment. ISKRA,
d.o.o. does not take any responsibility regarding the use and connection. If any doubt occurs regarding
connection and the use in the system which device is intended for, please contact a person who is
responsible for such installations.
In this chapter you will find:
2.1 Mounting 5
2.2 Electrical connection 6