SOLAR PV CONTROL SYSTEM.pdf

Communication System Methodology
Zigbee Technology is a communication protocol, where an X-Bee device is used for
the protocol. At the end point device I used an LCD display for monitoring
temperature and system process. After each of the system components was
established and worked, the remaining bit was to interconnect them and have a
single program to run it. I need to take readings from all nodes and transfer the data
from a remote area to a central destination (Control centre). The data read is then
sent from the Xbee module router and sent wirelessly to the other Xbee Coordinator
and information is displayed on the Computer. I programmed the Xbee modules
needed for the system Point to Point communication. I would have rather designed a
Point to Multipoint communication but for our prototype system a P2P was more
preferable.
Xbee Module: It is a very small piece of hardware that can connect wirelessly with
another using the Zigbee communication protocols. There are many different
models, including aerial types and power outputs for which my case I am using an
XB24 Series 2 model which can transmit 10m indoor or 100m outdoor which I have
tested and experienced. Other models of XBee can transmit up to 1.6km outdoor,
and that is interesting owing to the low power low cost and maintenance.
Temperature Connection: I used an LM35 sensor device which is calibrated to
record voltage deviation analogously and read via the Arduino pins. Since the
readings vary between 0 -1023, I needed to change them to voltage and temperature
(Celsius) using the following arithmetic equations:
val = analogRead(analogPin); // Reading hexadecimal inputs from 0 - 1023
volt = (val/1023)*5; // Converting Hexadecimal inputs to voltage by
mapping 0-1023 to 0-5v of the voltage peaks of the Arduino.
temp= volt*100; // Converts voltage read to Temperature in Celsius
Email: david.irungu@stu.kuct.ac.ke
57
2012