Solar control
Solar inverter control: every inverter, run as one plant.
An inverter app can tell you what the inverter did. It cannot see your plant load, your grid incomer or your DG. KONDUKTOR® EMS reads your inverters and meters together and sets inverter power over Modbus where the inverter allows it, so solar follows what the plant needs.
What solar inverter control means
Left alone, a grid-tied inverter produces all it can. Solar inverter control means setting from outside how much it may produce, and when. You may know it as inverter power control, solar curtailment, remote inverter control or a solar plant controller.
It matters whenever the plant cannot use or export everything the panels give: on holidays with no export allowed, or while a DG is running.
What you can control over Modbus
| Control | What it does | Used for |
|---|---|---|
| Active power limit | Caps inverter output in kW or as a percentage | Zero export, export limits, DG limits |
| Start and stop | Runs or stops the inverter on command | Panel washing, planned shutdowns, maintenance |
| Ramp rate | Sets how fast output returns after a limit lifts | Smooth recovery with a DG on the bus |
What is available depends on the make and model. Each make has its own Modbus register map, and some settings can only be changed by the installer.
What to read from each inverter
- AC power, daily units and lifetime units.
- Status and fault codes, so you know why it stopped.
- DC string voltage and current, where the inverter gives them.
- Inverter temperature, where the inverter gives it.
These come over the same RS-485 network as your panel meters, engineered for your plant as part of your project. A meter on the solar output gives you generation even if the inverter shares nothing.
Several inverters, one plant
Most commercial rooftop plants have several string inverters, sometimes from two makes after an expansion. If each one limits itself, they can over-correct and hunt up and down. Plant-level control sets one target and shares it across all of them, whatever their size.
- One limit for the site, shared in proportion to each inverter’s rating.
- An inverter that trips drops out of the sum, and the others can make up for it.
- Mixed makes run together, with each one addressed through its own register map.
- One view of the whole plant, in place of a separate app for each make.
What the control does in each situation
| Situation | What the control does |
|---|---|
| Load falls below solar | Holds export at zero or at your limit. See zero export controller |
| DG starts | Caps solar so the DG keeps its minimum load. See PV-DG synchronization |
| Panel washing or maintenance | Stops the inverters you choose for the time you set, where the inverter allows it |
| Surplus solar at midday | Starts chosen loads through Modbus I/O cards before throttling the inverters |
| Inverter trips | Alerts you the same day, instead of at month end |
Solar inverter monitoring
Control starts with knowing what the plant is doing. A tripped inverter shows as solar dropping while the sun is up, and it can go unnoticed for weeks when nobody checks the app. Grid outages, high voltage at midday, running on a DG and insulation faults after rain or panel washing are the usual causes, explained in solar, DG and grid monitoring.
- Generation today and this month, and yield per kWp.
- Generation against the weather, so cloud is not mistaken for a fault.
- An estimate of generation lost to dust, so cleaning follows data, not the calendar.
- Grid-off hours, when solar was lost with the grid.
Can your inverter be controlled?
Check these before you plan on it. We go through the same list with your inverter model.
- Does it have an RS-485 Modbus port, directly or through its logger?
- Does the maker publish a Modbus register map?
- Is there a writable active power limit in that map?
- Is the port free, or already held by the maker’s data logger?
- Does remote control need enabling in the installer settings?
- What does the inverter do if commands stop arriving?
Commercial and central inverter makes common in India
String inverters, common on commercial and industrial solar plants: Sungrow, Solis (Ginlong), Growatt, Deye, GoodWe, Huawei, Delta, TBEA, Sineng, FIMER, SMA, Fronius, INVT, Polycab and Havells.
Central inverters, used on larger plants: Sungrow, Sineng, FIMER (ABB’s former solar inverter business), TBEA, TMEIC, Hitachi Hi-Rel, SMA and Delta.
A make on this list does not mean every model can be controlled. Support varies by series, so we check your exact model against its maker’s Modbus register map before we commit to anything. If your make is not here, send us the model and we will check it the same way.
Brand names belong to their owners and are listed only to help you identify your inverter. KONDUKTOR® EMS has no tie-up with these makers and they do not endorse it.
Built to fail safe
Control sits above your electrical protection, never in place of it. Inverter protection and anti-islanding stay exactly as the maker built them. Each project is engineered so that a lost connection leaves the inverters at a safe limit agreed with your team, where the inverter supports one. Operators keep a manual override, only authorised users can change limits, and every change is logged.
Solar inverters in KONDUKTOR® EMS
- Solar generation, yield per kWp, share used on site, export, dust loss and grid-off hours.
- An inverter-trip alert that can be switched on per site.
- Inverter kW limited over Modbus where the inverter allows it, with several inverters run as one plant, engineered for your plant as part of your project.
- Modbus I/O cards for the switching around it, such as starting loads to use surplus solar.
- History, dashboard and control all on site, with no cloud server, and no Internet needed to run.
Common questions
Can a solar inverter be controlled over Modbus?+
Yes, where the make and model allow it. Many commercial inverters accept an active power limit over RS-485 Modbus, and some also accept start and stop commands. The maker’s register map shows what is available.
How do you limit solar inverter output?+
A controller writes an active power limit to the inverter, in kW or as a percentage of its rating. The inverter then backs off from its maximum power point and holds that output until the limit changes.
Does it work with Sungrow, Solis, Growatt or Deye inverters?+
These are among the common makes in India, and whether a model accepts an active power limit varies by series. We check your exact model against its maker’s Modbus register map first.
Can central inverters be controlled?+
It depends on the model and the plant. On larger plants the power limit is often set through the plant’s own controller, so we check that route as well as the inverter’s Modbus register map.
Can one system control inverters of different makes?+
Yes, where each make offers Modbus control. Each inverter is addressed through its own register map, and one site target is shared across them all.
Can we monitor inverters without controlling them?+
Yes. A meter on the solar output gives generation, yield per kWp and an inverter-trip alert. Inverter data over Modbus adds status and fault codes. Control can be added later.
Do we still need the inverter maker’s app?+
Keep it if your installer uses it for service. Check first that its data logger leaves the RS-485 port free or can share it.
Does limiting output harm the inverter?+
Power limiting is a normal inverter function, built in for export limits and grid support. The inverter simply draws less from the panels. Your maker’s manual gives the limits for your model.
What does solar inverter control cost?+
We quote per plant, based on your inverters, meters and what you need to control. Book a demo or message us with your plant details and we will tell you what it takes.
Run every inverter as one plant.
Book a live demo and see solar, grid and DG against the plant load on meters like yours.