Transcript Smartstat wireless thermostat

Final Presentation
April 20, 2010
Team Members
Read Caver
Albert Shannon
•Hardware Design
•Microcontrollers
•Wireless Communication
•Technical Documentation
•Hardware Implementation
•Energy Metering
•Microcontrollers
•GUI Design
•Technical Documentation
Steven Price
James Evans
•Software Development
•LCD Interfacing
•Energy Metering
•Hardware Implementation
•Software Design
•Hardware Implementation
•LCD Interfacing
•Website Maintenance
Overview

Introduction
 Problems Statement
 Solution

Constraints
 Technical
 Practical
Prototype Design
 Subsystem Testing
 System Testing
 Design II Goals

Introduction
SmartStat is a wireless thermostat with
energy computation abilities
 Used in both residential and commercial
settings
 Sets temperature for heat/AC to run,
provides power monitoring capabilities
 Thermostat module communicates
wirelessly with 2 power consumption
modules

NASA Sponsorship

Team SmartStat is sponsored by NASA.
 The team investigated the application of
wireless technologies for sensor
communication.
 Specifically, the IEEE 802.15.4 Standard for
wireless communication was implemented.
○ Emphasis on low power, low speed wireless
communications.
 The network can also be monitored via
Ethernet.
Problem

Currently, there is no practical way to
monitor the power consumption of
specific high powered systems such as
AC/heating units
Solution



Use low power
wireless technology
Send power
consumption
information to
control unit
(thermostat)
Send information to
RJ45 port
Technical Design Constraints
Constraint
Description
Temperature
Reading Range and
Accuracy
SmartStat must be able to read temperatures
in the range of 50°F to 100°F, with an
accuracy of 98% in the comfort range of 65°F
to 75°F
Energy Reading
The energy monitoring modules must
Range and Accuracy measure a voltage of 240Vac, maximum
current of 60A, with an accuracy of 98%.
Supply Voltage
The control unit must use 24Vac for supply
voltage. Energy monitoring modules must
use 120Vac for supply voltage.
Ethernet Interfacing
A RJ45 module must be used to allow for
energy monitoring via an Ethernet
connection.
Transmission
Distance
The wireless modules must have a range
equal to or greater than 500ft (unobstructed
line-of-sight).
Practical Constraints
SmartStat must be compatible
with the different types of HVAC
systems.
[1] Conventional
[2] Water and ground source heat
exchangers
[3] Air source heat exchanger
Health and Safety
[4]

The control module must not allow the
user to come into contact with hazardous
voltages; energy monitoring modules
must be sealed.
[5]
Prototyping Design
Power Monitor
(compressor)
Thermostat
Ethernet
(RJ45)
Power Monitor
(air handler)
Thermostat – Main Unit
Energy Monitoring Modules
RJ45 Module
Subsystem Testing

Main unit
 Basic thermostat controls
 Synapse wireless module communication
○ Energy data (covered in system test)
○ Number of wireless nodes connected (covered in system test)
Energy Monitoring Modules
 Energy metering
 Synapse wireless communication
 RJ-45 Module
 Lantronix module and GUI
 Synapse wireless communication
 Synapse Wireless Modules
 Power Supplies

Main Unit
Basic Thermostat Controls
Four LEDs to the right of breadboard represent the EM heat,
Valve, Compressor, and blower controls of the HVAC system,
respectively
Design Constraint – Satisfied
Range of 50°F to 100°F, with an
accuracy of 98% in the comfort
range of 65°F to 75°F
Energy Monitoring Modules
% Error Calculations
Output Pulses from ADE5577
Energy Metering IC
100W Bulb
Measured (ms)
Calculated (ms)
% Error
45
45.31
-0.68889
46
45.31
1.5
40W Bulb
Measured (ms)
Calculated (ms)
% Error
116
114.65
1.19469
113
114.65
-1.42241
Design Constraint – Satisfied
Energy Metering with 98% Accuracy
(prior to calibration)
Lantronix Module and GUI
Serial communication from a
TCP/IP socket to serial pin of
Lantronix module
Graphical User Interface used to
communicate with Lantronix XPort
module via TCP/IP socket
Wireless to Ethernet
Design Constrain – Satisfied
A RJ45 module must be used to allow for
energy monitoring via an Ethernet connection
Synapse Module to XPort communication
Synapse Modules
Distance vs Signal Strength of Synapse RFET Engine
Design Constraint – Satisfied
100
The wireless modules must have
a range equal to or greater than
500ft (unobstructed line-of-sight).
90
80
Signal Strength
70
60
50
40
30
20
10
0
<3m (~9.84ft)
100m (~328ft)
Unobstructed Separation Distance
200m (~656ft)
Power Supplies
• Each of the energy monitoring modules
must operate from 120Vac, and require
two voltage rails, 3.3Vdc and 5Vdc.
Design Constrain – Satisfied
Voltage in (AC)
Voltage out (DC)
5V rail
3.3V rail
Module 1
113.7
11.41
4.97
3.28
Module 2
113.8
11.29
4.96
3.28
System Testing
Wireless energy data received and displayed
Wireless node count (if !=2), some nodes are missing
Fulfilled Design Constraints
Constraint
Satisfied
Temperature Reading Range and Accuracy
Yes
Energy Reading Range and Accuracy
Yes
Supply Voltage
Yes
Ethernet Interfacing
Yes
Transmission Distance
Yes
Design II Goals

PCB Design

Enclosures
 Wall-mountable main unit
 Sealed energy monitoring modules

Increase the amount of displayed energy
information
 Decimal representation of consumed energy
 Cost of used energy
References
[1] “Why Choose Us,” Broward Factor Service. [Online] Available: http://www.browardfactory.com/why-choose-us.htm [Accessed:
Feb. 22, 2010].
[2] “You Can Save 80% per month on Your Electric Bill,” Energy Trio. [Online] Available: http://energytrio.com/energytrio.html
[Accessed: Feb. 22, 2010].
[3] “Air Handlers,” Amana. [Online] Available: http://www.amana-hac.com/Home/Products/AirHandlers/tabid/292/Default.aspx
[Accessed: Feb. 22, 2010].
[4] “Danger High Voltage,” Speedysigns. [Online] Available:
http://www.speedysigns.com/images/osha/large/DANGER50.gif[Accessed: Feb. 22, 2010].
[5] “Sign High Voltage clip art,” Clker.com. [Online] Available: http://www.clker.com/clipart-9328.html [Accessed: Feb. 22, 2010].
Questions?