Solar Energy Labs – Part 1
ENGR 1181
Today's Learning Objectives
 After today's class, students will be able to:
• Describe and build both a calibration and solar
meter circuit
• Convert decimal values to binary values
• Discuss how a potentiometer works
• Explain how a photodiode light sensor works
• Compare a pictorial image of a circuit to a
schematic wiring diagram
• Use a Photodiode Light Sensor and a Binary
Voltmeter circuit to measure the intensity of light
(in Watts/m2)
Solar Energy Meter
In lab today, you will build a solar energy meter circuit to
measure the energy intensity from a light source.
solar energy
meter
Output :
watts/m2
Solar Energy Meter Parts
 5 Volt power
supply
 DMM
 Breadboard
Solar Energy Meter Circuit Schematic and
Breadboard Layout – Final Circuit
Solar Energy Meter Circuit
2
1
+5V
4
3
+5V
2
1
+5V
Gnd
D0 (LSB)
14
D1
13
D2
12
D3
11
10
D4
D5
9
D6
8
7
6
V Input
5
V Out
V Out
5
6
Gnd
Gnd
D7 (MSB)
Binary Voltmeter
Light Sensor
3
4
+5V
+5V
+5V
+5V
PCB2
+5V
+5V
PCB1
LEDs
D7
D6
D5
D4
D3
D2
SHORT
WIRE
BINARY DISPLAY
D1
D0
Breadboard Setup
Build now in pairs!
Note DMM usage here
+5V
Gnd
Note jumpers
Measure the Power Supply Voltage, V = ______ Volts
Calibrate the Binary Voltmeter
Binary Voltmeter Calibration Circuit
DMM
2
1
+5V
4
3
+5V
+5V
+5V
+5V
+5V
PCB2
10K
14
Gnd
D0 (LSB)
13
D1
D2
12
11
10
9
8
D3
D4
D5
D6
7
6
5
3
+5V
D7 (MSB)
V Input
Binary Voltmeter
2
POT
1
LEDs
D7
D6
D5
D4
D3
D2
SHORT
WIRE
0 to +5 VOLTS
BINARY DISPLAY
D1
D0
TrimPot – varies input voltage
 Total resistance (Pin 1 to Pin 3) = 10 kOhms
 Resistance at Pin 2 varies by turning the small adjustment screw
(0 to +5V on Pin 2)
 Use it to change the input voltage to the Binary Voltmeter circuit
+5V
3
 It is a variable resistor.
10K
2
1
POT
Pins
123
8-Bit Binary Display
MSB
• The LEDs at the output of the Binary
Voltmeter are labeled from D7 to D0
LSB
LEDs
D7
D6
D5
D4
D3
D2
D1
D0
• The LEDs have two digital states, on
and off, representing the binary
numbers “1” and “0”
8-BIT BINARY DISPLAY
• D7 is the Most Significant Bit (MSB).
D0 is the Least Significant Bit (LSB)
• The 8-bit binary number can be
converted to a decimal number using
a formula
8-bit Binary Numbers
For example, convert binary 0 0 0 0 0 1 0 1 into a decimal:
MSB
LSB
00000101 = 5
…. + 0*23 + 1*22 + 0*21 + 1*20 = 5
The Calibration Circuit
10K
POT
3
+5V
1
2
•Place the TrimPot as
shown and:
+5V
Gnd
Short wire of LEDs must
be toward ground side
• Connect Pin 1 to
Ground
• Connect Pin 3 to +5
Volts
• Connect Pin 2 to V
Input on the Binary
Voltmeter
•Connect the LEDs
•Connect the Red DMM
wire to V Input
•
ENGR 1181
First-Year Engineering Program
Calibrate the Binary Voltmeter Circuit
Table A – record and store in lab spreadsheet
Set Voltage
Record Binary Numbers
Calculate Decimal Values
0
0000 0000
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
Full CW
Solar Energy Meter Circuit Schematic
and Layout
Solar Energy Meter Circuit
2
1
+5V
4
3
+5V
2
1
+5V
Gnd
D0 (LSB)
14
D1
13
D2
12
D3
11
10
D4
D5
9
D6
8
7
6
V Input
5
V Out
V Out
5
6
Gnd
Gnd
D7 (MSB)
Binary Voltmeter
Light Sensor
3
4
+5V
+5V
+5V
+5V
PCB2
+5V
+5V
PCB1
LEDs
D7
D6
D5
D4
D3
D2
SHORT
WIRE
BINARY DISPLAY
D1
D0
Task 3 – How the Light Sensor Works
• The Photodiode converts light
photons to a current
Isolar
Amplifier
Photodiode
V Output
• The Amplifier converts the current to
a voltage
• The voltage output of the Light
Sensor Board is proportional to the
intensity of sunlight (Isolar, Watts /
m2)
The calibration equation for the Solar Light Meter is:
Isolar = 5.0 Ndecimal (Watts / m2)
Use the Solar Energy Meter to measure
the intensity of a light source
Comment on shading LEDS and Blinking on least significant digits
 Place the spotlight in
the ring stand so that the
front of the bulb is 13
inches away from the
top of the Light Sensor.
 Make sure that the
Photodiode is directly in
the center of the beam.
 Measure the Intensity
of the light source at
distances of 23, 19, 15,
11 and 7 inches.
•
ENGR 1181
First-Year Engineering Program
Measure the Intensity of the Light Source at various distances
Distance
( Inches )
23.0
19.0
15.0
11.0
7.0
Binary Number
Decimal Value
Intensity
( Watts / m2)
Topic
Document Type
Marble Delivery System
None
Quality and Productivity
Executive Summary
Circuits
Executive Summary
Solar Energy – Part 1
--
Solar Energy – Part 2
Memo (Combined)
Beam Bending
Memo
Wind Turbine 1
--
Wind Turbine 2
Report (Combined)
Problem Solving Project 1
Problem Solving Project 2
Problem Solving Project 3
Project Notebook
(Combined)