Download 10_Sunrise_to_Sunset_Data

Sunrise to Sunset Data
Zent and Gerald
Open Circuit Voltage Setup
Current Logging Setup
Jan 12 Rainy Day Voltage Data
Jan 15 Sunny Day Voltage Data
Jan 21 Current Data
Some Conclusions
On the Side. . .
(Max II Data Logger Accuracy)
Voltage Logging Set Up
Notes:
Solar Cell
Connected
to a 10 M
ohm DMM
Data set 1 collected January
12 06:52 am to 6:13 pm. . .
Data set 2 collected January
15 06:03 am to 06:01 pm. . .
Sunrise was around 06:00
am. . .
Sunset was around 06:00
pm. . .
Current Logging Set Up
Solar Cell
Connected
to a 1.7 ohm
load
HP Logger Paralleled to a
“sense resistor” to divide current
Jan 12 Rainy Day Data
Jan 12 Rainy Day Data
Jan 15 Sunny Day Data
Jan 21 Current Data
Sunny weather from 0600 to 1100. . .
Cloudy/ rainy
weather from
1100 to 1420. . .
Cloudy weather from
1420 to 1600. . .
Sunny weather
from
1600 onwards . .
.
Some Conclusions

Voc is at its peak from 06:48 am to 5:33
pm
At this time, Voc sweeps from 35 V to 45 V
 Despite raining the whole day on Jan 12, the
Voc seemed to be in the same level for similar
times on the sunny Jan 15.


Irradiance highly affects current ratings as
expected. . .

current ratings radically changes during a day.
Max II Voltage Logger Updates

Accuracy Test
 249 data points were collected (roughly 2 hours). . .
 3 random points were measured with a
DMM and matched with the logger. . .
 Point 1 had a % error of 9%
 Point 2 had a % error of 2%
 Point 3 had a % error of 1.4 %



More accuracy tests needed
Error comes from . . .
 decaying reference voltage
 This can be solved by an IC Regulator?
 Temperature sensitive voltage divider
 This can be solved using temperature
insensitive resistors
Sir Tris helped with the ff:
 Over voltage protection implemented
 Divider circuit derivation conceptualized
but not yet implemented
 I have to make sure that the big cell
will see the computed resistances as open circuit