HT instruments SOLAR300N - Manual (Page 148)

SOLAR300 - SOLAR300N
EN - 146
7. MEASURING PROCEDURES
The instrument’s accuracy is grant only for the following system configuration:
NPV (Non-Photovoltaic) systems
 Single Phase systems (Phase, Neutral, Ground)
 Three Phase 4 wires systems WYE + ground,
 Three Phase 3 wires systems DELTA + ground
PV (Photovoltaic) systems
 Single-phase (Phase, Neutral, Earth)
 Three-phase (Three-phase 120° + Earth)
Further in this manual, the following definitions will be used, relative to PV systems
 Test: check the DC and AC efficiency parameters of a PV installation by using a fixed
(and not changeable) IP = 5s in quick way. No selection of recording parameters by
the user is necessary. For testing purposes, the connection of the unit SOLAR-0x and
relevant probes is strictly necessary. Furthermore, the solar irradiation measured will
have to exceed the minimum irradiance threshold (see § 5.3.3.3)
 Recording: Recording the DC and AC efficiency parameters of a PV installation by
using a IP selected by the user (see § 5.4.2.4). The connection of the unit SOLAR-0x
and relevant probes is strictly necessary. Furthermore, the solar irradiation measured
will have to exceed the minimum irradiance threshold (see § 5.3.3.3)
For the sake of simplicity, further in this manual, the word “string” will be used, although
often the term “photovoltaic field” would be more correct. From the point of view of the
instrument, the management of a single string or of more parallel strings (photovoltaic
field) is identical. Furthermore, the acronym MPPT (Multiple Power Point Tracker) shall
indicate the characteristic of the DC/AC converter (inverter), capable of maximizing the DC
power which can be taken from the photovoltaic field and the acronym PRp shall indicate the
Performance Ratio evaluated through active powers. See the § 10.3 for further details.
In case of test / recording on PV systems realized by means of Multi-MPPT (multi-string)
inverter, it will be possible to proceed as follows:
 Divide the system into more “sections” (one for each MPPT) and to test them
individually one after the other by appropriately sectioning the photovoltaic fields not
involved in the measurement.
Or
 Use the (optional) external unit MPP300, capable of managing the measurement up to 3
separate photovoltaic fields at the same time, each connected to an MPPT of the
inverter.
CAUTION
For the evaluation of the PRp only, the measurement of the DC (voltage and
current) is not strictly necessary. Conversely it is necessary if you want to evaluate
the performance of the photovoltaic section (ndc) and DC / AC conversion (nac)