Table of Contents
2. Product Description
The Etrel’s public charging station INCH DUO is highly configurable and can be tailored to the client’s specific needs. It allows simultaneous charging of two vehicles with power of up to 2 x 22,08 kW and is equipped with standard Type 2 sockets (EN 61851 or EN 62196-2).
The actual number of maximal charging power can differentiate the exact value for one charging spot considering voltage of 230 V is 22,08 kW.
Charging is limited to 32 A, however voltage specified as 230 V, can be between 207 V and 253 V (+- 10 %). This means that the actual charging power can be lower or higher of the specified 22,08 kW.
Another factor heavily influencing what is the charging power is the power factor (cos Fi), which is determined by the internal charger in the electric vehicle. This factor is always lower than one, meaning that all power is not active, there is also reactive component. The correct designation of charging power would therefore be 2 x 22,08 kVA (or 44,16 kVA).
No matter the specifics, the charging power of Mode 3 charging spot is commonly referenced as 22 kW (or 44 kW for charging station with two charging spots). This simplification is used in this document as well.
Charging station comes with the LCD screen that guides through the charging process and provides important charging information. Charging station comes with several connectivity options (including LTE and Ethernet) and open protocol support and can be seamlessly integrated in the smart home system.
Certified utility-grade meters as well as all optional utility feeder equipment are embedded in the station. The station can be equipped with an RFID identification module, which prevents unauthorized use and is necessary to enable different billing and reservation processes and other advanced functionalities. The station also supports remote identification with SMS or other external identification means.
The casing of the charging station is robust enough to withstand any unfavourable weather conditions and potential damage which may occur in open public areas. The compact dimensions of the charging station allow its installation in a small area, for example close to the edge of the pavement or roadside curb.
Modular design allows simple replacement of key components that can become damaged due to wear and tear or vandalism (especially the charging sockets). The station's service doors use a special three-point locking mechanism. The doors open outwards and to the side to simplify the work of maintenance staff.
Components Overview
The Etrel INCH DUO public charging station contains the following components:
Casing of the station,
two charging spots (Type 2 sockets, single- or three-phase),
main controller of the station,
LCD display that guides user through the charging process,
user identification module with RFID card reader,
ethernet communication connection point,
built-in smart energy meters for each charging spot,
electrical protection of each socket,
three-phase grid connection point equipped with standard safety protection.
Grid connection of the charging station, which contains terminals for all supply wires (L1, L2, L3, N and PE).
Energy meters for each socket. For normal functioning of the station, a working communication connection between the main station controller and the energy meters is required.
Differential and overcurrent protection of each socket.
Module for communication with electric vehicle (compliant with the IEC 61851 standard), socket voltage monitoring components, socket contactors.
Main station controller with RFID reader, RFID antenna and LCD display, control circuit power supply, and communication modules (Ethernet or GPRS router).
Figure 3: Arrangement of equipment inside the station
Base Specifications
Input: 2x230/400V~; 3W+N+PE; 50/60 Hz; 32 A max.
Output: 2x230/400V~; 3W+N+PE; 50/60 Hz; 32 A max.
Maximum charging power: 2 x 22 kW (3-phase)
Device power consumption:
From 5 W, depending on the actual configuration.
Grid Connection
The charging station can be connected directly to the electricity distribution network or to an existing electrical installation nearby. Supply power depends on the charging power of each socket (according to the configuration of the charging station).
The following supply power is required:
44 kW (64 A): 2 x three-phase charging spots, for each Type 2 socket is the maximum current 32 A per phase.
Supply power of the charging station must be dimensioned appropriately to enable simultaneous charging of two vehicles.
Charging power of each charging spot can be limited in the settings of the charging station on the scale between 6 A and 32 A. The charging station can also be set up to allow local power management so that when two vehicles are connected at the same time, the available maximum power is divided between the two vehicles. Power management can also be setup for a cluster of charging stations.
In the execution phase of the grid connection project, the following requirements need to be met:
Selectivity of the functioning of protection devices needs to be ensured:
The main overcurrent protection should be at least one class greater than the one used for the protection of the charging station or have a higher delay.
Differential protection (RCD) which is used in the charging station operates at a low current (ΔI 30 mA, without delay). The selectivity of this protection on the level of facility is achieved with a higher delay or a greater current differential.
Five wires are routed to the station, including three phase wires, grounding wire, and the neutral wire (when connecting to an existing installation). For single phase connection (slow charging option), only one phase wire with sufficient diameter can be routed to the station, together with neutral and earthing conductor. Dimensioning of the wires is determined in the project documentation. Grounding wire must be connected to the main grounding busbar.
Connection to the Station Operator's Communication Network
The charging station uses network connection to communicate with the Control centre to cyclically send information about its status, perform identification of users (on the Control centre level), forward events that occur during its operation and execute billing for the services performed.
The connection also enables communication from the Control centre towards the charging station, which enables remote access to the station for needs of maintenance or remote control.
The charging station could require a connection to the station operator's WAN network (charging infrastructure control centre). To access the WAN network via an internet connection, some additional security requirements need to be observed.
Network connection can be executed in several different ways:
Direct connection to the station operator's WAN network. Connection can be established directly with a UTP cable or a fibre optic converter.
Wireless connection. The station connects to an existing LTE 2G/3G/4G mobile network with an GPRS/UMTS router built into the station.
Specification of frequency bands and transmitting power (it is possible that not all modules are part of an actual device).
LTE module Frequency bands: LTE-FDD: B1 (2100 MHz), B3 (1800 MHz), B5 (850 MHz), B7 (2600 MHz), B8 (900 MHz), B20 (800 MHz) LTE-TDD: B38 (2600 MHz), B40 (2300 MHz), B41 (2500 MHz) WCDMA: B1 (2100 MHz), B5 (850 MHz), B8 (900 MHz) GSM/EDGE: B3 (1800 MHz), B8 (900 MHz) Transmitting power: 33dBm±2dB for GSM 24dBm+1/-3dB for WCDMA 23dBm±2dB for LTE-FDD 23dBm±2dB for LTE-TDD | LTE Router Frequency bands: 4G (LTE-FDD): B1 (2100 MHz), B3 (1800 MHz), B5 (850 MHz), B7 (2600 MHz), B8 (900 MHz), B20 (800 MHz) 4G (LTE-TDD): B38 (2600 MHz), B40 (2300 MHz), B41 (2500 MHz) 3G: B1 (2100 MHz), B5 (850 MHz), B8 (900 MHz) 2G: B3 (1800 MHz), B8 (900 MHz) Transmitting power: 21.9 dB |
RFID module Frequency band: 13.56 MHz (HF) Transmitting power: up to 8 dBm | |
Circuit Diagram
External Signal
Digital Inputs and Digital Outputs
Charger supports connecting four digital inputs and one digital output. Inputs and output are operating on 12 VDC, and maximal allowed load is 100 mA. Check pinout on the image below.
Figure 4: Pins of connector for digital inputs and output
The use and logic of these digital input and outputs is settable via web interface of the charging station.
Do not use external 12 VDC or 5 VDC for power supply. Digital output allows maximal load of 100 mA! Be careful not to make short circuit, which could be dangerous to persons and could also damage the charging station.