HT instruments SOLAR I-V - Manual (Page 48)

I-V400 - SOLAR I-V
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:
DPmax = 100 ABS [(Pmax – Pnom) / Pnom]
 check parameter which defines the final
response of test
Pnom = 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