What each device type shows and controls
The measurement cards of energy meters, PV inverters, batteries, hybrid inverters, EV chargers, heat pumps and virtual devices, and what the controller controls on each.
→ Overview
Every device belongs to a category (Device type in the Add device wizard). The category decides which circle on Home the device feeds, which box in Include to strategy is ticked by default and what the energy manager can do with it. The model decides which signals appear on Last measurements.
This chapter walks through the categories with the five devices of the documentation installation: an Eastron SDM630 grid meter, a SolarEdge PV inverter, a Sonnen FlexStack battery, an Etrel Inch EV charger and a Kronoterm KSM heat pump.
1 Sign convention
All devices use the same rule for power, current and energy direction:
| Value | Positive (+) | Negative (−) |
|---|---|---|
| Grid meter Active power | import from the grid | export to the grid |
| PV Active power | — | production (a producing inverter is always negative) |
| Battery Active power and Active power setpoint | charging | discharging |
| EV charger power | charging | — |
| Heat pump Import active power | consumption | — |
Separate Import active power and Export active power signals are always shown as positive numbers; their name gives the direction. Min active power is the largest power the device can deliver (shown negative), Max active power the largest power it can draw.
Home shows all values without a sign and uses the dots on the lines to show direction. The signs above apply to the device pages, Analyze, Archive and the CSV export.
2 Overview of the categories
| Device type | Home circle | Default in a strategy | What the energy manager does with it |
|---|---|---|---|
| Energy meter | Grid (meters with the Grid category) | Measurement device | Measures the grid connection: the basis for import and export limits and fuses. Not controlled. |
| Solar power plant | Solar | Regulated device | Limits (curtails) PV output when export must be reduced, for example on zero-export sites or at negative prices. |
| Battery | Battery storage | Regulated device | Sets charging and discharging power according to the strategy goal and the grid limits. |
| Hybrid inverter | Solar, Battery storage and Grid | Measurement and regulated device | Controls the battery part and limits PV, either with power setpoints or through the inverter's own operating modes. |
| EV charger | EV charger | Regulated device | Sets the charging current per phase within the free capacity of the grid connection and fuses. |
| HVAC | HVAC | Regulated device | Switches the heat pump or HVAC unit between operating states (for example Off, Eco, On, Boost) depending on available power and prices. |
| Other | Other | — | Measured; included in the Other consumption. |
| Emulator | depends on the emulator | — | A virtual device that combines or re-publishes measurements of other devices. |
3 Energy meter
An energy meter measures the power flowing through one point of the installation. A meter at the grid connection is the most important device of the site: the energy manager uses it to keep the import and export limits and the main fuses.
| Card | Signals | Meaning |
|---|---|---|
| Current | Current L1, L2, L3 | Current per phase, in A. Compared with the main fuses on each phase. |
| Voltage | Voltage L1, L2, L3 | Phase-to-neutral voltage, in V. Used by Voltage regulation. |
| Power | Active power | Total active power: positive = import, negative = export. In the example 2.5 kW import. |
| Power | Import active power, Export active power | The same power split into import and export, both positive. |
| Power | Import / Export active power - 1 minute average, - 15 minute average | Averages over 1 and 15 minutes, as used for billing of peak power by many grid operators. |
| Power | Reactive power, Import reactive power, Export reactive power | Reactive power in kVAr. |
| Energy | Import active energy, Export active energy | Energy counters in kWh, as on the meter's display. |
| Energy | Import reactive energy, Export reactive energy | Reactive energy counters in kVArh. |
| Other | Frequency | Grid frequency in Hz. |
| Other | Communication error | ON when the meter does not answer. |
What the controller controls: nothing. A meter has no Control type card. Add the grid meter to the strategy as a Measurement device.
When the grid meter is offline, the strategy cannot see the grid connection. It switches to its fallback values: batteries stop and PV and EV chargers are capped at their fallback power. Fix a Communication error on the grid meter first.
4 Solar power plant (PV inverter)
| Card | Signals | Meaning |
|---|---|---|
| Current | AC current L1, L2, L3 | Output current per phase. Negative, because the inverter delivers power. |
| Current | PV current | Current from the solar panels (DC side). |
| Voltage | AC voltage L1, L2, L3, PV voltage | Grid voltage at the inverter and voltage of the solar panels. |
| Power | Active power | Output power, negative while producing. −3.6 kW = 3.6 kW production. |
| Power | Export active power, Import active power | Output split into delivered (export) and drawn (import) power, both positive. |
| Power | Export active power limit | The output limit currently requested by the controller. Empty = no limit requested. |
| Power | Max. active power, Min. active power | Capability of the inverter: Min. active power −10.0 kW = rated output 10 kW. |
| Energy | Export active energy | Total energy produced, in kWh. |
| Other | Control type, Error, State name, Communication error | See Device measurements, charts and archive. |
What the controller controls: the output limit of the inverter. The energy manager curtails PV only as far as needed to keep the export limit (for example 0 kW on a zero-export site) or to avoid exporting at negative prices. Control types: Auto, Manual, Off (no production) and Boost (full production). Some inverters also have a fallback output that applies when the controller stops (see Device settings, edit and delete).
5 Battery
Battery systems show several cards: the battery itself, its inverter and, if it has one, its own grid measurement.
| Card | Signals | Meaning |
|---|---|---|
| Grid | Off-grid | ON when the battery system runs in backup (island) mode without the grid. The strategy then caps PV and EV chargers at their off-grid values. |
| Battery | Active power | Battery power: positive = charging, negative = discharging. |
| Battery | Max active power, Min active power | Largest charging power (+5.0 kW) and largest discharging power (−5.0 kW) the battery allows now. They drop to 0 at the SOC limits. |
| Battery | Current, Voltage | DC current and voltage of the battery. |
| Battery | State | Operating state reported by the battery, for example STANDBY. |
| Battery | State of charge, Min. state of charge, Max. state of charge | Current charge level in % and the limits the controller keeps. |
| Battery | Capacity, Max capacity | Energy currently stored (5.0 kWh) and usable capacity when full (10.0 kWh). |
| Battery | Import active energy, Export active energy | Energy charged into and discharged from the battery, in kWh. |
| Battery | Active power setpoint | Power last requested by the controller. Empty = no setpoint. |
| Inverter | Active power, Max/Min active power, State, Error | AC side of the battery inverter. State shows the inverter state, for example MPPT. |
| Other | Mode name setpoint | Operating mode last requested from the battery, for example Setpoint. |
What the controller controls: charging and discharging power (Battery active power setpoint) and, for batteries that support it, the battery's operating mode. The energy manager sets them from the strategy goal (for example self-consumption or peak shaving), the grid limits and the prices. Control types: Auto and Manual.
6 Hybrid inverter
A hybrid inverter combines a PV inverter, a battery inverter and often a meter at the grid connection in one device. It gets the categories Solar power plant, Battery and Grid, and its Last measurements tab shows one card per part, typically Grid, PV, Battery, Inverter and Load. The signals in each card have the same meaning and signs as for the separate devices above.
| Card | What it shows |
|---|---|
| Battery | The battery side of the inverter: Active power (positive = charging, negative = discharging), the power the battery can take or give right now (Max active power, Min active power), State of charge, stored energy (Capacity) and total size (Max. capacity), and the last Active power setpoint the controller sent. |
| PV | The solar input of the inverter. Active power is negative while the panels produce, like any production in the Configurator. Min active power is the most the PV side can produce right now. |
| Inverter | Operating State reported by the inverter (for example NORMAL or WAITING) and an Error flag. |
| Grid | The inverter's own meter at the grid connection, when it has one: Active power (positive = import, negative = export), the import and export limits currently set in the inverter, Off-grid (ON while the inverter runs in backup mode) and the energy counters. |
| Other | Communication error, Control type and Mode name setpoint (the native operating mode the controller last selected, when it controls the inverter through its own modes). |
When you add a hybrid inverter, step 2 of the wizard asks extra questions that depend on the model, for example on which Phase a single-phase inverter is connected, whether PV and a Battery are installed on it, and a User password some models need before they accept commands.
If Battery is set to No, the controller does not control the battery part of the inverter. If PV is set to monitoring only, it cannot limit the PV output, so it cannot keep the site below the export limit with this inverter.
What the controller controls: the battery part (charge and discharge power) and the PV output. Hybrid inverters with their own grid meter can be controlled in two ways: the controller sends power setpoints, or it switches the inverter's own operating mode (for example self-consumption or peak shaving) and lets the inverter regulate on its own meter. Which way is used is set on the strategy's Details tab (Preferred control mode (EMS or setpoint)).
If the site has both, decide which one measures the grid connection. Including both as measurement devices makes the strategy count the grid power twice.
7 EV charger
| Card | Signals | Meaning |
|---|---|---|
| Current | Current L1, L2, L3 | Charging current per phase, in A. |
| Current | Max. current per phase | Highest current the charger may use: detected from the charger or set on the Details tab. |
| Current | Per phase current setpoint | Current last requested by the controller. Empty = no setpoint. |
| Power | Import - active power | Charging power in kW. |
| Power | Max. active power, Min. active power | Charging power range of the charger (22.1 kW = 3 × 32 A). |
| Energy | Import active energy | Energy charged, in kWh. |
| Other | State name | State of the charger, for example AVAILABLE (no car connected). |
What the controller controls: the charging current per phase. The energy manager gives the chargers the power left over within the import limit and the fuses, and can restrict charging to PV surplus. With several chargers it shares the power, starting with the higher power distribution priority. Control types: Auto, Manual (fixed current) and Off. Chargers have no Boost.
8 HVAC and heat pumps
| Card | Signals | Meaning |
|---|---|---|
| Power | Import active power | Electrical power drawn by the heat pump, in kW. |
| Power | Export heat power | Heat delivered, in kW. In the example 12 kW of heat from 3 kW of electricity. |
| Other | Supply temp., Return temp., Outdoor temp., Pool temp. | Temperatures in °C. |
| Other | Sanitary water - temp., - temp. setpoint, - state name | Domestic hot water temperature, its setpoint and state. |
| Other | H.c. 1 … 4 - temp., - temp. setpoint, - room temp., - state name | Values of heating circuits 1 to 4. Empty = no sensor on that circuit. |
| Other | Operating state, State name, Load, Fan RPM, Supply flow | What the heat pump is doing (for example SANITARY_WATER), its load in %, fan speed and water flow. |
| Other | Sanitary water / Storage ECO and COMFORT offset | Temperature offsets the heat pump applies in its eco and comfort operation. |
| Other | Manual or auto activation, Alt. source activation | Activation flags reported by the heat pump. |
What the controller controls: the operating state of the heat pump. The energy manager chooses a state (Off, Eco, On or Boost) from the grid power or the prices, using the HVAC settings of the strategy, and the heat pump's driver translates it into commands for that model. The Kronoterm KSM has no Control type card: it is always controlled by the strategy it is included in. To keep it out of control, do not add it as a regulated device, or switch on read-only.
The controller does not set room or water temperatures directly. The heat pump's own controller keeps its comfort limits; the energy manager only shifts when it runs harder or less.
9 Other
Devices in the category Other are loads or meters that do not fit the categories above, for example a sub-meter of a building wing or a controllable relay. They feed the Other circle on Home only when the site has no grid meter; with a grid meter, Other is calculated from the grid power.
10 Emulator
Emulators are virtual devices. They have no hardware of their own, but are built from other devices:
- Combined devices: a virtual meter, PV plant, battery or hybrid inverter that adds up the measurements of several real devices. You choose which devices are included and excluded (Emulate measurements from the following devices, Include measurements, Exclude measurements). Use this, for example, to present several small batteries as one.
- Meter emulation: the controller answers like a standard energy meter (for example an Eastron SDM630 or Chint DTSU666) so that an inverter can read its grid measurement from the controller instead of from its own meter.
11 Checklist
- Each device is in the right category, and only grid-connection meters have the Grid category.
- Signs on every device follow the convention: import and charging positive, export, discharging and production negative.
- Every controllable device that the strategy should control is a Regulated device and in Auto.
- The grid meter is online and included as a Measurement device.