Most of the parameters of this sheet are only informative, some of them (bold) denote special features
| Multi-MPPT | Some inverters involve several MPPT inputs, which allow to connect PV arrays of different sizes, module types or orientations. |
| Normally each MPPT input may be considered as half an inverter (for a 2 MPPT); these are completely independent and have half the nominal power, they don't share the Power capacity of the full inverter. This is a limitation of the PVsyst simulation possibilities with respect to the manufacturer's specifications. |
| Unbalanced MPPT | When clicking this checkbox you have the opportunity of defining 2 different MPPT inputs (as available with some recent inverters on the market like the Tripower series of SMA). PVsyst defines the Main and Secondary MPPT inputs. See Inverter model: Multi-MPPT |
| Max ISC current | When defining unbalanced MPPT, the manufacturers use to specify the different inputs by their maximum ISC current, not the Power limitations. |
| Therefore, after sizing, PVsyst will allocate a Nominal power to each input, according to the ratio of the nominal PV power of each sub-array. |
| Number of DC inputs | Indicative for the acceptable number of strings (connectors), not used by PVsyst. Not to be confused with the number of MPPT inputs ! |
| String inverter | some manufacturers propose inverters which may directly receive the string terminals without intermediary circuitry. The device includes all securities normally mounted in a junction box on the roof (fuses, non-return diodes, overvoltage protections). The number of "String" inputs should of course correspond to the effective number of strings. |
| Transformer | May be transformerless (the best efficiencies), Low Frequency or High Frequency transformers. |
| The transformer is required for some applications like arrays of Amorphous modules (degradation of the TiO2 electrode) or some old back-contact modules (which should be polarized with respect to the ground voltage).. |
| Master/Slave | some inverters may operate in the "Master/Slave" mode, one of them ensuring the MPP tracking, and transmitting this information to the other one(s). This allows to turn ON the required number of devices, improving the efficiency at lower powers. In this configuration the full array should be connected to all devices at a time, in parallel. For the Master/slave operation, you should define the Power threshold from which the second device will be turned ON. See Inverter model: Multi-MPPT |
| Internal Master/Slave | Many big inverters are announced as "master/slave" devices. These are assemblies of standard units of a defined power, which operate internally in Master/slave mode. This operation mode results in a very good efficiency curve (of the whole device) with a sharp elbow at low powers. These should not be treated as "Master/Slave" in the simulation process as this behavior is already taken into account in the efficiency. |
| Auxiliaries consumption | Fans or other accessory device consumption, to be deduced from the inverter output available energy. For the simulation, the auxiliaries consumption is not automatic, even if defined here: it should be explicitly specified in the "Detailed Losses" part. |
| Night consumption | Usually negligible. If less than 0.05%, will not appear on the loss diagram. |
| Other specifications | give additional information about the configuration, features and securities of the device, not used in the simulation. |
| Isolation Monitoring | is a continuous check of the isolation of the PV array with respect to ground. |
| DC Swich | indicates if the device includes it, otherwise it should be foreseen externally on all DC inputs. |
| AC Swich | indicates if the device includes it, otherwise it should be foreseen externally. |
AC Disconnect adjust: the inverter should cut the AC connection immediately when the grid voltage goes out of a given AC voltage range (in Europe, 230 V or 400V + 6% and - 10%). This feature allows to adjust these limits.
| ENS | indicates that the shut-down security in case of grid defection works on the basis of the grid's impedance measurement. This system is mandatory in Germany. |
