Transcript Week 3

Amey Rane
Madhur Srivastava
Tejas Pandit
Varun Sivakumar
Success Criteria [PSSC]
 An ability to measure power consumption of plugged-in




devices over time
An ability to communicate with a base unit using RF and to
upload recorded information on a web server using the
Ethernet interface
An ability to turn devices on/off remotely
An ability to set up intelligent power plans to turn off
devices either after a fixed amount of time or after fixed
power consumption
An ability to use touch screen interface to control operating
parameters of the power management system
Block Diagram
Power Source
Internet
Current inputs
Switch
Electrical
Appliance
Adapter
DC Control
RF
Microcontroller
(Base Unit)
Solid State
Relay
Ethernet
Microcontroller
(Adapter)
Current
Sensor
RS232
Intel
Atom
Processor
VGA
LCD
Touch screen
Base Unit
USB
Constraints for adapters
 Low power microcontrollers for the adapters
 Accurate current sensors for correct power
measurement
 Zero crossing relays for switching inductive loads
 RF integration with the microcontroller for
remote/base unit communication
Constraints for base station
 LCD with VGA port to interface with the Intel Atom
board
 Touch screen with the same dimensions as the LCD
screen and a USB interface
 Microcontroller with inbuilt transceivers to
communicate with the adapters
 Ability to connect to the internet
Atmel Microcontroller
Microcontroller
ATMEGA128RFA1
# of pins
64
# of I/O pins
38
Program Memory (kB)
128k(Flash) 4k(EEPROM)
RAM (kB)
16k
TX/RX Byte Frame Buffer
128
Power Consumption
16mW
Documentation
Yes
Price
processing for sample
Adapter circuit elements
Solid State Relay
Opto 22 – 120D25
Carlo Gavazzi – RA 2410LA
Optical Isolation
Yes
No
Zero Switching
Yes
Yes
Control Voltage
3-32
3-32
Price
$26.50
$36
Current Sensor
Tamura - L18P***D15
Allegro - ACS710
Output Voltage
4V
2.5V
Accuracy
+-1%
+-2.2%
Price
$12.50
$22.00
Questions