This project is developed for monitoring and controlling switch gear contact temperature using wireless sensor network.
An on-line monitoring system of contact temperature inside HV switchgear cabinet based on Zigbee has been studied and developed, which consists of the power monitoring center, the temperature monitoring unit and the temperature display unit.
The contact temperature of switchgear is measured by the temperature monitoring center, which is timely sent to the temperature display unit by Zigbee wireless communication. The Zigbee transmits the data. Another Zigbee is connected with the PC unit. The PC receives the data and displays in detailed manner.
Also if the temperature limit exceeds a level, the PC automatically sends signal to the controlling unit through Zigbee. Thus the particular switch gear unit will be shut down. An interface is designed to connect to the power monitoring center, and the corresponding temperature of different contacts or buses inside different cabinets can be browsed and monitored remotely. Thus one can monitor and control the switch gear contact temperature in online manner
LM 35 is used as temperature sensor. This temperature sensor senses the temperature of the particular switchgear.. It sends signal to the microcontroller through buffer.
The microcontroller used in this circuit is PIC16F877A. It is a 40 pin microcontroller with four I/O ports. The program written in the microcontroller can be erased electrically and re written again. It has inbuilt ADC. The signal from the sensor is given to the microcontroller.
According to the signal received from the sensor, it controls the Zigbee transmitter section through driver section and relays. The microcontroller program is written in assembly language. The assembly language program is compiled to form "hex" code. The "hex" code is written in the microcontroller using PIC write software with the help of PIC writer