# EMS Function Introduction and Operation
### SG Ready
#### Interface Settings
The cloud platform setting interface is shown below:
Supports independent configuration of dual DO channels. The detailed function parameter configuration page is shown below:
#### Logic Description
Normally open / normally closed dry contacts can be configured. To use this function, select the channel and enable it.
When the control mode is set to ON, the normally open contact will change to normally closed during the set time period. Outside the time period, the normally open contact remains open.
When the control mode is set to OFF, the normally closed contact will change to normally open during the set time period. Outside the time period, the normally closed contact remains closed.
When the control mode is set to AUTO, the normally open and normally closed contacts are triggered according to the settings below. After configuration, the time control function is disabled.
When SOC is set to “at least” mode, the Aux contact of the load shall be connected to the N/O terminal.When the battery SOC meets the set condition (regardless of the set delay):
When the feed-in power is higher than the set “Switch on” power, the N/O terminal closes (load turns on).
When the feed-in power is lower than the set “Switch off” power or power is purchased, the N/O terminal opens (load turns off).No action is taken when the supply power is between the two set values.
When SOC is set to “at most” mode, the Aux contact of the load shall be connected to the N/C terminal.When the battery SOC meets the set condition (regardless of the set delay):
When the feed-in power is higher than the set “Switch on” power, the N/C terminal closes (load turns on).
When the feed-in power is lower than the set “Switch off” power or power is purchased, the N/C terminal opens (load turns off).No action is taken when the supply power is between the two set values.
### Self-Consumption Function
#### Interface Settings
Self-consumption strategy settings:
There are two ways to enter the self-consumption logic: via the time-based charge/discharge function to set the discharge period. When the current time is outside all time periods, self-consumption is activated by default.Aside from the set time intervals, the system will run in self-consumption optimization mode by default.
**Cut-off SOC for time-based discharge & self-consumption, the setting location is shown below:**
**Grid Feed-in Power**
Two grid feed-in power settings are supported: fixed grid feed-in power or grid feed-in power percentage. The setting location is shown in the figure below.
#### Logic Description
When mains supply is present and PV power generation is sufficient, PV power is used to supply the load first. The surplus PV power charges the battery. When the battery reaches its maximum charging power, the excess power is fed into the grid without exceeding the maximum grid feed‑in limit.
### 1Time-Based Charge and Discharge Function
#### Interface Settings
Start and end time, period, charging power, charge/discharge cut-off SOC can be configured. Up to 28 groups can be set. Time segments cannot overlap or cross days. This function is a weekly cycle configuration. The interface is shown below:
#### Logic Description
**Time Period Charging**
When mains supply is available, during the charging period, the battery is charged by PV power first. If the PV power is insufficient to meet the battery charging power, power will be taken from the grid to charge the battery.When PV power exceeds the battery charging power, the surplus PV power supplies the load.When the battery reaches the Charging Cutoff SOC, battery charging stops. At this time, PV power supplies the load. If there is additional PV power, it will be limited according to grid feed-in requirements.
**Time Period Discharge**
When the system is not within the discharge time period, it enters the charge enable & discharge disable logic.
**Charge Enable, Discharge Disable**
When the system is not within the discharge time period, it enters the charge enable & discharge disable logic.
### Peak Shaving and Valley Filling Function
#### Interface Settings
Set the peak shaving and valley filling parameters via the interface below:
#### Logic Description
When mains supply is available, peak power and valley power can be set.Within the set time period, the power purchased from or sold to the grid will be limited to the configured peak or valley value.
When power consumption exceeds the peak limit, the system discharges the battery to reduce power purchased from the grid.
When power consumption is below the valley limit, the system charges the battery to increase power purchased from the grid.
### Manual SOC Calibration Function
#### Interface Settings
Manual SOC calibration or cancellation can be configured in the interface shown below.
#### Logic Description
After this function is enabled, if the system is grid-connected and the battery is chargeable, forced charging of the battery will start immediately. Power is taken from PV first; if PV power is insufficient, power will be taken from the grid.
When the battery charging flag changes to charge prohibited, the calibration discharge process will start. The calibration logic will exit when the discharge drops below the calibration start SOC or the reserved SOC.
### Periodic SOC Calibration Function
#### Interface Settings
Automatic SOC calibration can be enabled in the interface shown below, and the SOC calibration time period and calibration cycle can be configured.
#### Logic Description
Trigger condition: The current calibration date is the same as the next calibration date, and the current time is later than the next calibration time.
Operation logic: Charge the battery at full power, with priority given to PV power.
Exit logic: When the battery charging flag changes to charge prohibited, the calibration discharge process starts. The calibration logic exits when the discharge falls below the calibration start SOC or the reserved SOC.
### Forced Charging Function
#### Interface Settings
Enter the forced charging configuration interface through the interface below.
#### Logic Description
There are two types of forced charging trigger logic:
a. Manual forced chargingThe system will charge until it reaches the charging cutoff SOC, then exit forced charging.
b. Forced charging triggered by battery undervoltage (this function is forced enabled)When the system detects battery under voltage, it enters forced charging logic.The system exits undervoltage forced charging when the battery cannot be charged or reaches the charging cutoff SOC.
### Time Period Grid Feed-in Function
#### Interface Settings
Set the time period grid feed-in parameters in the interface shown below:
#### Logic Description
The system controls charging and discharging to make the grid feed‑in power meet the target value, subject to the maximum grid feed‑in power limit.
Up to 6 time periods for forced battery discharging can be set. Time periods cannot overlap or cross days. This function runs on a daily cycle.
Grid feed‑in power can be set individually for each discharge period. The configured power value represents the grid feed‑in power limit of the surplus power after the household electricity meter supplies the load.
System output power refers to all available discharge power except grid power, including PV power (if available) and battery discharge power.
If grid feed‑in power is set to 0, the system output only needs to supply the load.
If the required system output power for the set feed‑in power is greater than the actual achievable output power, the system will feed in at the actual maximum available power.
Only one discharge cut-off SOC can be set for the forced battery discharge function.If the battery discharges to the cut-off SOC during a grid feed‑in period, the forced battery grid feed‑in function will not be triggered even within the set time period, until the battery is charged above the cut-off SOC again.
The energy report displays data before today; today’s data can be viewed the next day.
### German Ripple Control Receiver (RRCR)
#### Interface Settings
To enable RRCR:First, open the corresponding IO ports. For port definitions, refer to the relevant section.
Then configure RRCR parameters: enable the function and set the maximum grid feed‑in values corresponding to the four dry contacts.
#### Logic Description
The EMS judges whether the RRCR function is enabled.
If disabled, the EMS executes the maximum grid-tie logic according to the default grid-tie coefficient settings.
If enabled, the closed state of each dry contact indicates different maximum grid feed-in limits.For example, when the EMS detects that K1 is closed, the system will control in accordance with the maximum grid feed-in value preset for K1.
For detailed grid feed-in power description, refer to the relevant section.
### Off-grid Function
#### Interface Settings
Configure off-grid access and cut-off SOC on this interface:
#### Logic Description
When the system is in off-grid mode, the load on the Backup side is powered by both the battery and PV.
When the battery SOC is less than or equal to the load cut-off SOC, or the battery is in a discharge-prohibited state, the system controls the PCS to shut down. At this time, if the system detects the presence of PV, the system starts up and uses PV to charge the battery until the battery SOC reaches the load access SOC value, then reconnects the load.
### UPS RESERVE Function
#### Interface Configuration
Set the function enable on the following page:
#### Logic Description
When the battery SOC is lower than the discharge cut-off SOC, the UPS reserve function is triggered, and the system starts forced charging of the battery. When the battery SOC is higher than the discharge cut-off SOC, the forced charging exits.
### MODBUS-TCP/RTU Dispatch Function
#### Interface Configuration
No configuration is required; dispatch is allowed by default.
#### Logic Description
The dispatch function supports customers to communicate with our EMS via TCP using the MODBUS TCP/RTU protocol.It supports real-time system operation data query and power dispatch parameter issuing.(Protocol content complies with MODBUS TCP/RTU specification.)
### APIDispatch Function
#### Interface Configuration
For detailed logic, refer to the API dispatch specification document.Logic Description
#### Logic Description
For detailed logic, refer to the API dispatch specification document.
### South Australia Dispatch Function
#### Interface Settings
The power grid company shall set command parameters via the network interface. The cloud platform interface is shown below:
#### Logic Description
Supports the power grid company in controlling PCS inverter power, system grid-feed power, and inverter power ramp rate via dispatch commands.
### Dual Power Supply Function
#### Interface Settings
There is a Dual Power Supply Function Enable option on the generator function settings interface.If this option is checked, it indicates the site is a dual power supply application site.If unchecked, it indicates the site is a non-dual power supply application site, i.e., a conventional off-grid generator application site.
#### Logic Description
The PCS automatically switches according to the power access status of the mains or generator port. The EMS switches to the grid-tied with mains or grid-tied with generator logic based on the PCS operating mode.
### PCS Remote Maintenance (Grid-Connected Parameters)
#### Interface Settings
The interface for remotely modifying PCS grid-connected parameters on the cloud platform is shown below:
#### Logic Description
On the cloud platform issuing interface, select the device to be modified and click Query to view the current grid‑connected parameters of the device.
Currently supported functions include:
Stage 1 and Stage 2 over‑/under‑voltage protection (over/under voltage ratio and time can be set)
Stage 1 and Stage 2 over‑/under‑frequency protection (over/under frequency value and time can be set)
After modifying the parameters, click Save to apply.The EMS will issue the parameters to the PCS, and the PCS will perform grid‑connection protection according to the issued parameters.
### German 14A Regulation
#### Interface Settings
The function configuration page is shown below:
#### Logic Description
After this function is enabled, it is triggered by the dry contact controlled by the external controller.When the external trigger issues a power limit command, the EMS limits the PCS AC-side power drawn from the grid until the AC-side power drops below 4.2 kW\.Once triggered, this function will restrict the AC-side power purchase of all other strategies except the off-grid strategy and generator control strategy.
### Battery Bypass Function
#### Interface Settings
The function configuration page is shown below:
#### Logic Description
After this function is enabled, the EMS continuously sends bypass enable control commands to the BMS.The BMS bypasses the faulty PACK according to the operating status, ensuring the battery cluster operates normally.
Fault bypass alarms are listed below:
General over-temperature of poles
General over-temperature of cells
General low charging temperature of cells
General low discharging temperature of cells
General over-voltage of cells
General under-voltage of cells
Cell temperature sensor fault
Cell wiring harness fault
### Battery Consistency Calibration Function
#### Interface Settings
After the ByPass function is enabled, the battery consistency calibration option will appear, with 4 sub-options indicating the operating conditions under which this function takes effect.
#### Logic Description
The EMS continuously sends battery consistency calibration commands to the BMS according to the set values and the current grid-connected/off-grid status.During charging, the BMS bypasses high-SOC PACKs based on the PACK operating status to reduce their charging; during discharging, it bypasses low-SOC PACKs, so that the SOC of each PACK in the battery cluster is calibrated to be consistent.
### One-click Shutdown Function
#### Interface Settings
The settings page is shown below:
#### Logic Description
After this function is enabled, the EMS continuously sends shutdown commands to the PCS.The PV on the DC side stops generating power, and the backup port stops supplying power to the load.
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