Upload
mithun-j-ram
View
27
Download
2
Tags:
Embed Size (px)
Citation preview
2012
Author: Mithun JTenet Technetronics Date: 27/09/2012
Loadcell based weighing and alert system
i Tenet Technetronics
Contents
Introduction.......................................................................................... 2
Hardware Overview............................................................................. 2
Hardware futures....................................................................... 3
Mode of Operation .............................................................................. 3
Application .......................................................................................... 6
Loadcell based weighing and alert system www.tenettech.com
ii Tenet Technetronics
LEDs for indicating Safe, warning and danger level
Buzzer for alerts
DC power adapter 16x2 LCD
3 switches for Mode selection
Loadcell
Introduction
Loadcell based weighing and alert system is used measure the weigh and to alert the user if the weight is less
than or equal to the threshold value. It can operate in four modes. Modes are selected with the help of three toggle
switches provided, each switch will enables one mode if non of the switch is selected fourth mode will be selected. The
three modes will operates for three fixed threshold values, in the fourth mode will act as weighing machine.
Hardware overview
The device make use Atmega328 microcontroller for controlling the entire system, it need 12 V dc input for operation. With the help of Loadcell it gets the weight of the object hanged to it, three LEDs indicates the safe, warning and danger levels in first three modes selected by switches, in fourth the LEDs were not used, the buzzer helps in alerting the user when it reaches warning level or danger level.
Hardware Futures Atmega328
Loadcell based weighing and alert system www.tenettech.com
iii Tenet Technetronics
Power supply
Green led
1st switch selected
Load
Mode
Yellow led
Warning level
Power supply
Load
INA125p 16x2 lcd buzzer LEDs Switches Loadcell
Mode of Operation 1. Mode 1:
The system will enter this mode by selecting 1st switch, in this mode the threshold weight is 25gm. If the load weight is less than 25gm it is danger level which is indicated by red LED and danger message on LCD and buzzer sound, if load is greater than 25gm and less than 45gm then it is warning level which is indicated by Yellow LED and warning message on LCD and buzzer sound, if the load is above 45gm it is safe level which is indicated by green LED and safe message on LCD and buzzer will be off.
Fig2: Mode 1, safe level
Loadcell based weighing and alert system www.tenettech.com
iv Tenet Technetronics
Red led
Danger level
Power supply
1st switch selected
Load
Fig3: Mode 1, Warning level
Fig4: Mode 1, Danger level2. Mode 2:
The system will enter this mode by selecting 2nd switch, in this mode the threshold weight is 50gm. If the load weight is less than 50gm it is danger level which is indicated by red LED and danger message on LCD and buzzer sound, if load is greater than 50gm and less than 70gm then it is warning level which is
Loadcell based weighing and alert system www.tenettech.com
v Tenet Technetronics
All led are OFF
Power supply
No switch selected
Load
indicated by Yellow LED and warning message on LCD and buzzer sound, if the load is above 70gm it is safe level which is indicated by green LED and safe message on LCD and buzzer will be off.
3. Mode 3:The system will enter this mode by selecting 3rd switch, in this mode the threshold weight is 100gm. If
the load weight is less than 100gm it is danger level which is indicated by red LED and danger message on LCD and buzzer sound, if load is greater than 100gm and less than 120gm then it is warning level which is indicated by Yellow LED and warning message on LCD and buzzer sound, if the load is above 120gm it is safe level which is indicated by green LED and safe message on LCD and buzzer will be off.
4. Mode 3:The system will enter this mode if no switches are selected. In this mode the will acts as weighing
machine which will read and displays the weight of the object hanged to it.In this mode none of the LEDs will be used and even the buzzer will be off.
Fig5: Mode4
Applications 1. Industries where they need alert if liquid level is less than some threshold2. Hand held weighing machine.
Loadcell based weighing and alert system www.tenettech.com