PLC based IOT controlled Electric Protection System for Lineman
PLC based IOT controlled Electric Protection System is based on a circuit breaker that can only be remotely controlled by the lineman himself, designed to provide security to the maintenance staff and households while repairing the electrical lines. When operated manually we see fatal electrical acc
2025-06-28 16:34:30 - Adil Khan
PLC based IOT controlled Electric Protection System for Lineman
Project Area of Specialization Internet of ThingsProject SummaryPLC based IOT controlled Electric Protection System is based on a circuit breaker that can only be remotely controlled by the lineman himself, designed to provide security to the maintenance staff and households while repairing the electrical lines. When operated manually we see fatal electrical accidents to the linemen are increasing during the electric line repairing due to lack of communication and coordination between the maintenance staff and electric substation staff. In order to avoid such accidents, the circuit breaker can be designed such that only authorized person can operate it with the help of password-based IOT application. By using it operator can control the circuit breaker while he is away from the workstation and keypad is used to enter the password to control it when the operator is in the workstation. A relay is used to open or close the circuit breaker. Any wrong attempt to open the breaker an alert will be displayed on the mobile screen through the application and display the status on the HMI. Furthermore, the system will detect faults, maintain a history profile of the connection and provide alarms to linemen if the connection is running on above 70 percent of the prescribed load.
Project ObjectivesTo develop a system to resolve a communication gap between Lineman and Grid Station.
Control a Circuit Breaker via Android Application or by a keypad with a dedicated password in case of an offline operation.
Alarm the Lineman if the line is on more than 70 percent load
To Detect fault in the distribution system
To Maintain a maintenance profile of the connection
Project Implementation Method- Structural Design:
- Wooden plank
- Plywood
- Bulb Holders
- Switch board
- Connecting Wires
- Nails
Firstly, we are to cut the wooden plank to our required Test Bed, and make a frame of it, on which a ply wood is to be installed for easy installation of equipment. Then as per test we are going to install the load, that happens to bulb holders in this preliminary stage, that would depict a format of a small residential society. Bulb holders and switch board were nailed to the plywood, while holes were drilled in the respective position for electrical connections.
Our PLC of Fatek is relay based, but just to add a second line of defense of protection we made this module. This module comprises of a relay that get’s excited on 24v DC and 400mA exact to the industrial standards, and can be used to control a load of 220 V. This provides an isolation between the load and our controller acting as PLC Controlled Circuit Breaker.
The 24v relay we’re using has five legs in general. Two are to energize and deenergize the coil that makes the heavy load switch via deviating the electromagnet. The leg between these two legs is known as the common pin, this leg is directly with the contact that is deviated when the coil energizes and deenergizes. The two pins on the opposite end of the coil are of Normally Open and Normally Close. Normally open is a contact when the coil is deenergized it is short. This is used in cases where frequent switching is not required, and usually on condition is preferred. The other contact is Normally Open. This contact will be short with common only when the coil is energized. This is the condition we’ll be utilizing, by this feature the lineman will be turning a certain load on and off when required.
For CT and PT design we first got linear transformers, and then with the help of bridge rectifier DF10 and a combination of resistors and capacitors to further smoothen the curves to get a pure DC output for our PLC’s Analogue module to read. The Led was installed so that one can visually see if our module is on or not, while the pot is there to deal if the input voltage is more than 220V AC, and to limit the output to 10v DC that is the maximum input of our analogue module as per industrial standards.
The stepped down voltage from either the Current Transformer or the Potential Transformer shall be fed to a four legged bridge rectifier called DF10. The two legs of the bridge rectifier are to be connected to the transformer’s output, while the other two legs on the opposite side give out ‘direct current’ which is not entirely correct. The rectifier gives an out put of ripples and with increase and decrease in potential from the transformer the ripples become even, jeopardizing the reading itself. In order to suppress these uneven curves capacitors were connected to it with a combination of resistors to suppress the ripples at different stages.
It is an alternative to SCADA system, which makes it economical and due to the protocols used, it makes it open for plethora of applications.
- Easy to use
- Efficient way to troubleshoot.
- Reduced ManPower
- Maintenance Profile
- Ease of Access
- Transparent
- Applicable on every overhead Transmission line
- Compatible with the concept of Micro Grids and Smart Grids
.
Technical Details of Final DeliverableOur main objective is to give the control to the lineman, and reduce his risk of life and others that accompany him. Hence, by the help of the components mentioned above we will be using the preventive technique to reduce the phenomenon of inspection. With the help of the CT and PT attached to each lane of our test bed, and the NodeMCU depicting the behavior of a user, our programmed PLC shall alert the lineman when the load crosses 70 percent of the prescribed load and automatically cut of the supply when the load exceeds 90 percent without anyone’s will. In case of a short circuit our PLC will cut off the supply and protect the load, the housing society in the case of our Testbed. Furthermore, with the help of CT and PT’s the lineman can instantaneously view the load at runtime, and also shut down an entire portion in case of maintenance.
By making this all possible, we used the communication protocols of ModBus, and MQTT for IoT.
Our final product gives a password protected access to the LineMan of the transmission line, and salso gives him access to the data proofile of the line, so that he can implement the maintenance rule of prevention is better than inspection.
| Item Name | Type | No. of Units | Per Unit Cost (in Rs) | Total (in Rs) |
|---|---|---|---|---|
| Total in (Rs) | 66422 | |||
| 5v 2A chargers | Equipment | 6 | 100 | 600 |
| Wooden Board | Miscellaneous | 1 | 690 | 690 |
| 7/29 wire | Equipment | 1 | 3100 | 3100 |
| Male Female Plugs | Equipment | 3 | 40 | 120 |
| Leds | Equipment | 12 | 320 | 3840 |
| 200W bulbs | Equipment | 2 | 60 | 120 |
| 100W bulbs | Equipment | 2 | 31 | 62 |
| Bulb Holders | Equipment | 12 | 40 | 480 |
| Glue Gun | Miscellaneous | 1 | 370 | 370 |
| Glue Sticks | Miscellaneous | 37 | 10 | 370 |
| 5v Relay Module | Equipment | 3 | 1167 | 3500 |
| 24 Relay Module | Equipment | 3 | 117 | 350 |
| FBs-U2C-MD | Equipment | 1 | 2800 | 2800 |
| MT807iE | Equipment | 1 | 22000 | 22000 |
| Fbs-20MAR-2 | Equipment | 1 | 11700 | 11700 |
| Fbs-6AD | Equipment | 1 | 11000 | 11000 |
| HMI plc cable | Equipment | 1 | 350 | 350 |
| Jumper Cables | Equipment | 2 | 85 | 170 |
| NodeMCU | Equipment | 4 | 450 | 1800 |
| CT | Equipment | 3 | 500 | 1500 |
| PT | Equipment | 3 | 500 | 1500 |