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ess:ess_mode_2_and_3 [2019-08-15 12:39]
guy_stewart replace venus-device with GX device
ess:ess_mode_2_and_3 [2020-02-17 09:55]
iburger [1.3 - Mode 3]
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   * Note that there is no AC sensor necessary, since the inverter/charger will act as a 'dumb' bi-directional inverter/charger. It will act on the external command given, which can for example be 'take 2000W from AC in, or feed back 100W through AC in'.   * Note that there is no AC sensor necessary, since the inverter/charger will act as a 'dumb' bi-directional inverter/charger. It will act on the external command given, which can for example be 'take 2000W from AC in, or feed back 100W through AC in'.
  
-Available control points include the switch (on, charger-only, inverter-only, off), a power setpoint in Watts: regulates the power on the ac-input, and more.+Available control points include the switch (on, charger-only, inverter-only, off), a power setpoint in Watts: regulates the power on the ac-input, and more. Similar to Mode 2, there are various ways to access those control points. Refer to the detailed section below. 
 + 
 +=== Mode 3 with a managed battery === 
 +When using Mode 3 with a managed battery, please note that the maximum discharge current sent by the battery will be ignored. The implemented control loop should take care of discharge limits communicated by the battery. 
 + 
 +The exception to the above rule is a zero discharge limit. If a managed battery requests a zero discharge limit, the Multi will stop discharging the battery. 
 +    * If grid power is available, the Multi will go into passthru. 
 +    * If grid power is not available, the Multi will switch off. 
 + 
 +The maximum charge current sent by a managed battery is however always heeded and cannot be overruled by the setpoint.
  
-Similar to Mode 2, there are various ways to access those control points. 
  
 ===== 2. Mode 2 in detail ===== ===== 2. Mode 2 in detail =====
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   * As an alternative to running the control loop externally, using ModbusTCP, it is also possible to run code on the CCGX itself and update the AcPowerSetpoint via D-Bus. We have one customer that is running a MQTT client on the CCGX, written in Python, that gets the control-loop output as updates from a MQTT broker. And the Python script sends them to the Multi, using D-Bus service com.victronenergy.vebus.ttyO1, and path /Hub4/AcPowerSetpoint   * As an alternative to running the control loop externally, using ModbusTCP, it is also possible to run code on the CCGX itself and update the AcPowerSetpoint via D-Bus. We have one customer that is running a MQTT client on the CCGX, written in Python, that gets the control-loop output as updates from a MQTT broker. And the Python script sends them to the Multi, using D-Bus service com.victronenergy.vebus.ttyO1, and path /Hub4/AcPowerSetpoint
  
-===== 5. Response times ===== +===== 5. Response times and ramp speed =====
- +
-Depending on which components are used, and from which point the communication is sent to the inverter, there are several factors involved in the response time: the Color Control GX, ModbusTCP, MK3 microprocessor, the Assistant, and the Multi itself. +
- +
-The (now deprecated) Hub-4 Assistant had no rate limiter.+
  
-The ESS Assistant has a rate limiter. In the currently latest version (162it is at 400W per second+There are multiple factors that determine the response time to a (digital-command to feed in:
  
-Backgroundlate 2016we copied the Hub-4 Assistant, and named the copy "ESS Assistant"And then development on the Hub-4 Assistant was stopped. The reason for the rate limiting is that without that there are regulation problems (overloads and such) when the mains is weak (long cables and such resulting in a relatively high impedance). More information on that [[ve.bus:grid-codes-and-loss-of-mains-detection|here]], as well as in the main ESS manual.+  - Latency and communication speed of all components in the communication chainModbusTCP or MQTTGX Device, MK3 microprocessor, ESS Assistant, internal communication in the Multi itself. 
 +  - Rate limiting imposed by the used Country Grid code. Code "Otherhas no rate limiting, Code "Europe" allows installer configurable rate limiting, many other codes have fixed a powerup ramp up. 
 +  Hard coded rate limiting in the inverter/charger firmware: as per ESS version 162 it is set to 400W per second. The reason for this rate limiter is that without that there are regulation problems (overloads and such) when the mains is weak (long cables and such resulting in a relatively high impedance). More information on that [[ve.bus:grid-codes-and-loss-of-mains-detection|here]], as well as in the main ESS manual.
  
 ===== 6. Further examples for external control ===== ===== 6. Further examples for external control =====
ess/ess_mode_2_and_3.txt · Last modified: 2020-07-09 14:32 by iburger