HT instruments PVCHECK User Manual
Page 17
PVCHECK
EN - 15
5.2.3. Selection of the compensation relationship of temperature effects
This option allows selecting the relationship to be used to correct the measurements
performed according to the modules’ temperature as regards the calculation of nDC
efficiency. The following modes are available:
-
T.Mod.:
Correction factor Rfv2 related to PV module Temp. (Italian guideline CEI-82-25)
-
T.Env:
Correction factor Rfv2 related to environmental Temp. (Italian guideline CEI-82-25)
-
nDC:
nDC correction according to module temperature
CAUTION
If it’s performed a test according to Italian guideline it is recommended to select
“T.Env.” correction
Corr.
Type
Temperature used (Tcel)
Calculation of nDC
Ref.
T.Mod.
s
Tmoduli_Mi
Tcel
C)
40
Tcel
(se
100
40)
-
(Tcel
-
1
C)
40
Tcel
(se
1
fv2
R
hence
n
STC
p
dc
P
G
G
Rfv
P
nDC
2
CEI
82-
25
T.Env.
800
Irr
20
Tamb
Tcel
NOCT
nDC
s
Tmoduli_Mi
Tcel
n
dc
cel
p
STC
P
P
T
G
G
nDC
25
100
1
- - -
where:
Symbol Description
Measurin
g unit
p
G
Irradiance measured on PV module surface
2
W/m
STC
G
Standard Irradiance = 1000
2
W/m
n
P
Rated Power = sum of all Pmax values of the section of the PV plant being
measured
kW
dc
P
DC power measured at the PV generator’s output
kW
2
Rfv
Correction factor depending on the Temperature of PV Cells (Tcel) measured or
calculated according to the type of selected correction relationship
Absolute value of the thermal coefficient of Pmax of the PV modules included in the
plant section being measured.
C
%/
NOCT
(Normal Operating Cell Temperature) = Temperature the cells under reference
conditions are brought to (800W/m
2
, 20°C, AM=1.5, air speed =1m/s).
C
%/
For further details see § 11.1