This document describes an embedded PIC microcontroller-based motor protection system. Motors are critical to industry but are vulnerable to failures that harm productivity. A complex protection system is needed to prevent overloading while avoiding spurious tripping. The proposed system monitors voltage, current, power, temperature and frequency to detect overloads, under/over voltage, overheating and flames near the motor. It uses sensors, signal conditioning circuits and a PIC microcontroller to control relay drivers and provide alarms and parameter readings.

1. ELECTRICAL PROJECTS ABSTRACT
Embedded PIC Microcontroller Based Motor Protection
System
Motors are the heart of the load in any manufacturing and process
industries. They drive the conveyors, pumps, fans, blowers, cranes,
compressors, mills, extruders and so many production and process
equipments. Hence motors become very critical in the todays’s industry and
they are to be protected at all costs as the failure of motors cause enormous
money loss due to production loss, downgrading of the processed materials
and production of scrap.
Also the rhythm of production is affected and hence productivity suffers.
With the complex nature of the loads of the motor and capability of the
motor in mind, one has to carefully utilize the motor to its safe operating
level without damaging it. Under utilization of the motor and also spurious
tripping are to be avoided. Hence a complex motor protection system is the
basic requirement which satisfies all the relevant factors.

2. The Feaures of the Project are
Over Load Tripping Prevention:
Over Voltage and Under Voltage Detection:
Over Temperature Detection:
Flame Detection in Motor Area
Graphical illustration of Parameters
Parameters like Voltage, Current, Power, Temp etc can be viewed
graphically .
The parameters supported by this project includes
1. Motor Voltage
2. Motor Current
3. Motor power
4. Motor Temperature
5. Line Frequency

3. Features
• Microcontroller based advanced technology
• Protection against over current
• Cause of the alarm/trip indication
Application areas
• Steel mills
• Sugar plants
• Plastic
• Paper and textile industries

4. BLOCK DIAGRAM
CPU
Serial
Port
Alarm
RS232 Voice
Transistor Interface Output
Driver
Voltage
Signal PT
+5V
Microcontroller Conditioning
Power Supply Board Board
Pic16F877
CT Current
Intruder Switchi Relay
Sensor ng Ckt Drivers Zero Motor
Crossing
Detector
Relays
Thermist Volt for
or Divider Control
Outputs
PT
Flame Sensing
Dual Power Supply
Sensor Circuit

5. BLOCK DIAGRAM
CPU
Serial
Port
Alarm
RS232 Voice
Transistor Interface Output
Driver
Voltage
Signal PT
+5V
Microcontroller Conditioning
Power Supply Board Board
Pic16F877
CT Current
Intruder Switchi Relay
Sensor ng Ckt Drivers Zero Motor
Crossing
Detector
Relays
Thermist Volt for
or Divider Control
Outputs
PT
Flame Sensing
Dual Power Supply
Sensor Circuit

6. BLOCK DIAGRAM
CPU
Serial
Port
Alarm
RS232 Voice
Transistor Interface Output
Driver
Voltage
Signal PT
+5V
Microcontroller Conditioning
Power Supply Board Board
Pic16F877
CT Current
Intruder Switchi Relay
Sensor ng Ckt Drivers Zero Motor
Crossing
Detector
Relays
Thermist Volt for
or Divider Control
Outputs
PT
Flame Sensing
Dual Power Supply
Sensor Circuit

7. BLOCK DIAGRAM
CPU
Serial
Port
Alarm
RS232 Voice
Transistor Interface Output
Driver
Voltage
Signal PT
+5V
Microcontroller Conditioning
Power Supply Board Board
Pic16F877
CT Current
Intruder Switchi Relay
Sensor ng Ckt Drivers Zero Motor
Crossing
Detector
Relays
Thermist Volt for
or Divider Control
Outputs
PT
Flame Sensing
Dual Power Supply
Sensor Circuit