Smart Solar Monitoring System – SS3 Solar Photovoltaic Installation & Maintenance Lesson Note (First Term)

Subject: Solar Photovoltaic Installation and Maintenance

Class: SS 3

Topic: Using IoT Tools to Monitor Solar Systems (Practical Guide)

A smart solar monitoring system connects a solar inverter or charge controller to the internet through a Wi-Fi or GSM dongle. It sends live data, such as solar input, battery percentage, load and grid status, to an app on a smartphone or tablet. Users check the system, find faults and help batteries last longer.

Behavioural objectives

By the end of the lesson, students should be able to:

1. List the tools needed to connect a solar system to a monitoring app.
2. Connect a Wi-Fi dongle to an inverter and pair it with a monitoring app.
3. Read the live data on the dashboard (PV power, battery percentage, grid status and load).
4. Explain common app alerts and what to do about them.
5. Use the data to make the batteries last longer.

Why do we monitor a solar system with an app?

In our previous theory lessons, we talked about how “smart” solar systems have a voice. Today, we are going to learn how to listen to that voice.

As a solar technician or homeowner, you cannot sit on the roof all day watching the panels. You need a way to see what is happening while you are sitting in your living room or even while you are travelling to another city.

The goals of this practical

1. To connect a solar system to a monitoring tool.
2. To read and understand the “Live Data” (what is happening right now).
3. To use this data to make the batteries last longer.

What tools do we need?

Before we start, look at the “Tech Kit” required for a smart setup.

• The smart inverter or charge controller: This must have a communication port (usually labelled RS485, RS232 or CAN).
• The Wi-Fi/GSM dongle: This is a small device that plugs into the inverter. It acts like a “mobile phone” for the solar system, sending data to the internet.
• A smartphone or tablet: This is where we install the monitoring app.
• An internet connection: A MiFi or a mobile hotspot gives the dongle a path to the “Cloud.”

How do we connect the inverter to the app?

Follow these steps to get the data from the wires to your phone screen:

1. Plug in the dongle: Make sure the solar system is OFF. Plug the Wi-Fi dongle into the communication port of the inverter and screw it tight.
2. Power up: Turn the system back on. You will see a small light (LED) blinking on the dongle.
3. The handshake (pairing): Open the monitoring app on your phone. Most apps will ask you to scan a QR code on the side of the dongle. This tells the app exactly which inverter it is talking to.
4. Connect to Wi-Fi: Enter your Wi-Fi password into the app. The dongle will now stop blinking and stay solid. This means it is “Online.”

How do we read the dashboard?

Once you are logged in, you will see a “Dashboard.” It usually looks like a flow chart with moving bubbles or lines.

What to look for

• PV power (solar input): If it is 12:00 PM and this number is 0W, something is wrong. A wire may be loose or the panels may be very dirty.
• Battery percentage: If this is dropping too fast while the sun is still out, you might be using too many heavy appliances (like a pressing iron or heater).
• Grid status: If you are connected to NEPA/PHCN, the app will show you if the grid is “Live” or “Down.”

Practical exercise

Look at the app and record the “Current Yield.” Switch on a high-power device (like a microwave). Watch how the “Load” number jumps up. This shows you how much energy your appliances “eat.”

How do we troubleshoot using the app?

An IoT system tells you when it is “sick” before it “dies.”

Common app alerts

• “Low Battery Voltage”: You have used too much power at night. Turn off some lights immediately.
• “Overload”: You have plugged in something too heavy for the inverter.
• “Device Offline”: This usually means your Wi-Fi or data has run out. The solar system is probably working fine.

Final discussion

If you are a technician and a customer calls you saying “My lights are blinking,” how does checking the app first save you time and transport money?

Evaluation

1. List the four items in the “Tech Kit” for a smart solar setup.
2. Why must the solar system be OFF before you plug the dongle into the inverter?
3. What does a dongle that stops blinking and stays solid mean?
4. At 12:00 PM the PV power on the dashboard shows 0W. Give two possible causes.
5. What does the “Device Offline” alert usually mean?

Assignment

Write the four steps for connecting a Wi-Fi dongle to an inverter and pairing it with a monitoring app. Then describe what each of these dashboard readings tells you: PV power, battery percentage and grid status.