How do I connect to a Phasor Measurement Unit (SEL-311C) using it's serial port RS232? I am able to do that using Teraterm but not in Matlab

I am very new to Matlab. I used Teraterm to communicate with the device (Transmission and protection system SEL-311C). I can send commands and receive the responses in Teraterm but while I try to use Matlab, I cannot get anything. This device is very specific used case device that I am using for my University Project and doesn't have a big screen where I can verify the data transmission. I am stuck as I want to use a Matlab program to receive the phasor data using this device and analyse the data using a Matlab program.

Answer 1

[UDAYA PEDDIRAJU]

Hi Sudhir,

Connecting to SEL-311C via Serial Port in MATLAB:

While Teraterm works, replicating it in MATLAB requires the Instrument Control Toolbox (check using ver('instrument')). You'll also need the SEL-311C's communication protocol specifications (user manual).

Steps:

1. Prerequisites:

• MATLAB with Instrument Control Toolbox
• SEL-311C communication protocol details

Communication Object Creation:

s = serial('COM3'); % Replace with your port number
s.BaudRate = 9600;  % Adjust based on SEL-311C settings
s.Parity = 'none';
s.DataBits = 8;
s.StopBits = 1;
fopen(s);

Sending Commands and Receiving Data:

% Send a command (replace with specific command)
fwrite(s, 'MEAS:VOLT?');  % Example command
s.Timeout = 10;  % Set timeout (adjust as needed)
% Read incoming data (adjust format based on response)
data = fscanf(s, '%f');  % Example: Read a floating-point value
fclose(s);

1. Data Analysis:Use MATLAB's data analysis tools (e.g., extracting magnitudes, generating plots) on the received data.

Remember:

• Replace placeholders with your specific values.
• Implement error handling for robustness.
• Consider instrument drivers (if available) for simplified communication.

This approach allows you to establish serial communication with the SEL-311C, retrieve phasor data, and leverage MATLAB's analysis capabilities for further exploration.

You can refer to https://www.mathworks.com/help/slrealtime/rs-232.html and https://www.mathworks.com/help/sps/ref/phasormeasurementunitpmuthreephase.html for relevant MathWorks documentation.