I-V400w - I-V500w - SOLAR I-Vw - SOLAR I-Ve
EN - 46
6.2.3. Meaning of measurement results
The parameter measured and calculated by meter have the following meaning:
Parameter Description
Pmax
Maximum power of module measured by the meter
DPmax
Difference % of maximum measured power from nominal power (@ STC)
FF
Fill Factor %
Voc Open
voltage
Vmpp
Voltage on point of maximum power
Isc
Short circuit current
Impp
Current on point of maximum power
Table 2: List of parameter measured by the meter
Where:
Nom
Age
Nom
Age
MAX
MAX
P
P
P
DP
100
%
check parameter which defines the final test response
100
%
.
1
YearDegr
Yrs
Oper
P
P
Nom
Nom
Age
Nom
P
= nominal power of module
FF = 100 x [(Vmpp x Impp ) / (Voc x Isc)] = Fill Factor
represents a kind of “efficiency” of
module/string as it is a ratio between the maximum power measured and the open power
The meter gives the following final response:
Response Condition Note
OK
- Tol
(-)
+
Meter
Meas
Tol
(+)
-
Meter
(1)
OK*
The previous relation (1) is not verified but the following is valid:
- Tol
(-)
Meas
Tol
(+)
(2)
NO OK*
The relations (1) and (2) are not verified but the following is valid:
- Tol
(-)
-
Meter
Meas
Tol
(+)
+
Meter
(3)
NO OK
None of the relations (1), (2) and (3) are verified
(4)
where:
Tol
(-)
= Tol
(-)
(%)*Pnom
Negative tolerance in absolute value, declared by manufacturer
Tol
(+)
= Tol
(+)
(%)*Pnom
Positive tolerance in absolute value, declared by manufacturer
Meas
= Pmax – Pnom
DPmax which defines the difference between measured values
and declared values
Meter
Absolute error of the measurement chain (meter + transducers in the point of
measure) considering the error % and the declared dgt
(1) OK
Positive response of test also considering the error of measurement chain
(2) OK*
Response of test positive less than the error of measurement chain
(3) NO OK*
Response of test negative less than the error of measurement chain
(4) NO OK
Negative response of test also considering the error of measurement chain
