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Note the following: WARNING Siemens products may only be used for the applications described in the catalog and in the relevant technical documentation. If products and components from other manufacturers are used, these must be recommended or approved by Siemens. Proper transport, storage, installation, assembly, commissioning, operation and maintenance are required to ensure that the products operate safely and without any problems.
Table of contents Overview..............................5 About the document......................5 About the feature ........................ 5 Description............................. 7 Working Principle ......................... 7 Sub-Features........................8 Communications........................ 12 Trip line (Emergency loop) ....................14 Modbus registers (ELMS to SICHARGE)................15 Modbus registers (SICHARGE to ELMS)................16 Commissioning ............................
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Table of contents External Load Management System Operating Manual, 07/2022, A5E52045935-AA...
This document is an annex to the operating instructions for an optional feature named the "External Load Management System" developed for SICHARGE D (EV charger). It is always to be referred to in conjunction with the Operating Instructions (8EM5907-0AA00-1AA7), Repair Instruction (8EM5907‑0AA00‑4AA1), and Software Handbook (8EM5907‑0AA00‑4AA6) which...
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Overview 1.2 About the feature Note ELMS feature also works without an AC incomer meter. Note The PLC can only control the real power consumption P of the charger. The reactive power due to installed EMC filters cannot be controlled. In standby mode, real power P is low, and the reactive power Q constitutes the major part of the apparent power S.
4 kW for each active charging port. • The charger considers the maximum installed AC/DC-converters and the power limit specified by the SICHARGE D configuration backend (Config_PowerLimit), and dynamically calculates and sends back to ELMS the maximum power limit that is possible (G_Power_Max).
Description 2.2 Sub-Features Sub-Features The ELMS has various sub-features which are explained briefly in this section. Some of the sub- features are used by default and are necessary to ensure proper functioning, while some are options for providing minor functional enhancements. Power limit handshake The charger sends the minimum and maximum supported power limits to the ELMS dynamically over the communication interface.
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Description 2.2 Sub-Features Power limit fallback In case of loss of communication detected by the charger and the ELMS, the charger switches to the power limit fallback setpoint. This signal is sent by the ELMS to the charger via the software interface.
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Description 2.2 Sub-Features It is highly recommened to use this sub-feature in cases wherein Modbus polling is done by ELMS every few hundred millseconds. Actual EVSE power consumed (optional) In cases where the charger is equipped with an AC income meter option and there is no error active in the charger related to a communication loss with this meter, the charger sets the internal measurement available (IMA) flag in its status word.
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Description 2.2 Sub-Features Outlet EV charging states EV charging states are detected by the charger using the control pilot signal (CP) which is a hardwired signal for communication between the charger and the EV. These are available for both AC and DC charging outlets and are transferred by the charger to the ELMS. Pilot states are enumerated by integer values as shown in the table below.
Description 2.3 Communications Connected and ready (no ventilation required) Connected and ready (ventilation required) Disconnected F/Invalid Error: Got no valid pilot state Communications Communications are implemented between SICHARGE and the ELMS using the Modbus TCP communication protocol. The SICHARGE charger acts as the Modbus server, while the ELM acts as the Modbus client and initiates queries to the charger.
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Description 2.3 Communications Network port forwarding When multiple SICHARGE chargers are used, they have the same IP address for the PLC. For the ELMS to communicate with them correctly, the port forwarding concept must be implemented. The charger consists of the RUT240 router which takes care of this function. An example of this concept with multiple SICHARGE chargers connected to the ELMS with networking IPv4 address is show below.
Description 2.4 Trip line (Emergency loop) Trip line (Emergency loop) Trip line is a safety feature implemented by using hardwired cables and is important to ELMS functionality. It is a signal loop connected between the ELMS and safety emergency switch loop in each SICHARGE charger individually.
HB_ELMS_A = true. Please note that for this heartbeat monitoring sub-feature, the ELMS does not need to generate any pulses and is only required to return the pulses issued by the SICHARGE on status word bit 15 - Heartbeat SICHARGE D (HB_S) on this flag. External Load Management System...
Description 2.6 Modbus registers (SICHARGE to ELMS) EVSE active power limit setpoint (G_PowerLimit) Main power limit setpoint for SICHARGE in cases where the ELMS feature is active (ELMS_LLA = true) and no communication loss is detected between SICHARGE and ELMS. Measured average EVSE active power (EMA_Power) Measures the average active power consumed by SICHARGE on an external energy meter installed at the ELMS end.
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Description 2.6 Modbus registers (SICHARGE to ELMS) Name Addr Type Factor Units Pilot state uint Calculated average active output power (P_DC1) uint Actual DC output voltage (U_DC1) uint Calculated DC output current (I_DC1) uint DC2 outlet status and measurements Pilot state uint Calculated average active output power (P_DC2) uint...
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Description 2.6 Modbus registers (SICHARGE to ELMS) Status word 1 The bit-wise split of the status word from SICHARGE to the ELMS and its description are discussed below. Note that in this case LSB is Bit 0 and MSB is Bit 15. •...
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Description 2.6 Modbus registers (SICHARGE to ELMS) • Bit 10 – DC4 EV Connected (DC4_EV_Con) SICHARGE sets this flag to true when the EV is connected to the DC4 outlet and is waiting in the cable check phase with authentication done. SICHARGE sets this flag to false when the charging phase is no longer active at this outlet.
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Description 2.6 Modbus registers (SICHARGE to ELMS) Min EVSE power (G_Power_Min) SICHARGE calculates the minimum active power required from the grid to support the current charging outlets and auxiliary loads. It is expected that the ELMS provides power limit setpoints (G_PowerLimit and G_FallbackPLim) which are at least equal to, or greater than, this value. Max EVSE power (G_Power_Max) SICHARGE calculates the maximum active power required from the grid based on the installed capacity and further limits set from SCB.
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Description 2.6 Modbus registers (SICHARGE to ELMS) ACx outlet status and measurements In the ACx representation, the letter 'x' denotes the number assigned to the SICHARGE charging outlet. It can begin with number 1 for the AC outlet, for example. • Pilot state Outlet EV charging states decoded from the hardwired CP line in the charging cable connected between SICHARGE and EV.
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Description 2.6 Modbus registers (SICHARGE to ELMS) External Load Management System Operating Manual, 07/2022, A5E52045935-AA...
Commissioning Settings on SICHARGE configuration backend (SCB) Carry out the following steps to activate and set the ELMS feature: • Press the Change Configuration button. • Load the data from the charger and then press the REQUEST MAINTENANCE MODE button in the PLC Configuration. •...
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Commissioning 3.1 Settings on SICHARGE configuration backend (SCB) • Press the Router Configuration button External Load Management System Operating Manual, 07/2022, A5E52045935-AA...
Commissioning 3.2 Safety loop testing using TRIP line • Enable "Open ports through VLan on WAN port to the PLC", and enter IP address 10.20.37.x to act as the IP address of the Modbus server for the ELMS communication. Ensure that the IP address of the controller on the ELMS side is in the same 10.20.37.y range.
Commissioning 3.3 Power limiting via ELMS 6. Wait for charger booting to complete. 7. Ensure the ELMS is activated from the SCB (see section 3.1 for more details). 8. Activate the ELMS via the communication interface and ensure Control Word 1 – bit 0 (ELMS_LLA) is set to "true".
Commissioning 3.4 Fallback power limit via ELMS Fallback power limit via ELMS Carry out the following steps to test the fallback power limiting via the ELMS: 1. Complete steps 1–7 from section 3.3 and check that the power limiting is working as expected.
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Commissioning 3.4 Fallback power limit via ELMS External Load Management System Operating Manual, 07/2022, A5E52045935-AA...
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