HT instruments SOLAR300N - Manual (Page 189)

SOLAR300 - SOLAR300N
EN - 187
The reason why MPPTs are used is simple: a photovoltaic system without MPPTs may
operate anyway; however, with the same solar irradiation, it provides less energy.
There are inverters with 1, 2 or also 3 inbuilt MPPTs available on the market. Typically, the
inverters with more than one MPPT are used in systems where:
- The different photovoltaic systems it consists of “forcibly” have different inclinations or
directions. In this way, each single MPPT manages its own photovoltaic field,
maximizing its performance for the corresponding irradiation and temperature
characteristics (without being influenced by the other photovoltaic fields).
- A greater service continuity is sought. With more MPPTs it is possible to put one single
photovoltaic field out of service, while the others continue producing energy towards
the remaining MPPTs.
10.4. VOLTAGE ANOMALIES
The meter is capable of recording all those TRMS values as voltage anomalies, calculated
every 10ms, beyond the percentage thresholds of Voltage Reference (Vref) set during the
programming from
1% to 30% in steps of 1%. These limits remain unchanged
throughout the recording period.
The reference are set to:
Nominal Voltage Phase to Neutral:
for Single Phase and 4 wires three phase system
Nominal Voltage Phase to Phase: for 3 wires three phase system
Example1: Three Phase System 3 wires.
Vref = 400V, LIM+= 6%, LIM-=10% =>
High Lim = 400 x (1+6/100) = 424,0V
Low Lim = 400 x (1-10/100) = 360
Example2: Three Phase System 4 wires.
Vref = 230V, LIM+= 6%, LIM-=10% =>
High Lim = 230 x (1+6/100) = 243,08V
Low Lim = 230 x (1-10/100) = 207,0V
For each voltage anomaly the instrument records:
 The number corresponding to the phase where the anomaly occurred.
 The “direction” of the anomaly: “UP” and “DN” identify voltage drops (sag) and peaks
(swell) respectively.
 The date and time of the event beginning in the form day, month, year, hour, minutes,
seconds, hundredths of second.
 The duration of the event, in seconds with a resolution of 10ms.
 The minimum (or maximum) value of voltage during the event.