1. Introduction
The GreenBlue GB620 E Energy Meter Wattmeter is designed to help you monitor the electricity consumption of your household or office appliances. By accurately measuring energy usage, voltage, current, and power, this device enables you to identify inefficient appliances and manage your electricity expenses effectively. Its clear, rotatable display and user-friendly interface make it an essential tool for energy management.
2. Safety Instructions
- Ensure the device is connected to a properly grounded French E type socket (220-240V / 50-60Hz).
- Do not exceed the maximum load of 3680W (16A). Overloading can cause damage to the device and connected appliances, and poses a fire hazard.
- Do not disassemble or attempt to repair the device. Refer all servicing to qualified personnel.
- Keep the device away from water, moisture, and extreme temperatures (-10°C to +40°C operating range).
- This device is for indoor use only (IP20 protection rating).
- Ensure children cannot access the device when it is plugged in.
- Unplug the device from the wall socket before cleaning. Clean only with a dry, soft cloth.
3. Product Overview
The GreenBlue GB620 E consists of a main plug unit and a rotatable display unit. The display shows various electrical parameters and features two control buttons for navigation.

Figure 3.1: Front view of the GreenBlue GB620 E Energy Meter, showing the main unit with a French E type plug and the attached rotatable display. The display indicates various electrical parameters.
3.1. Components
- Main Unit: Houses the internal circuitry and the French E type plug for connection to the wall socket.
- Output Socket: French E type socket for connecting the appliance to be monitored.
- Rotatable LCD Display: Shows real-time measurements and accumulated data. The display can be rotated for optimal viewing angle.
- Control Buttons: Two buttons located on the top of the display unit for navigating through different display modes and settings.
3.2. Dimensions

Figure 3.2: Diagram illustrating the dimensions of the GreenBlue GB620 E Energy Meter. The display measures 5 cm by 5 cm, and the main unit measures 5.5 cm by 5.5 cm by 4 cm.
4. Setup
- Unpack: Carefully remove the GreenBlue GB620 E from its packaging.
- Plug In: Insert the energy meter into a standard French E type wall socket. Ensure it is securely seated.
- Connect Appliance: Plug the appliance you wish to monitor into the output socket of the energy meter.
- Power On: Turn on the appliance. The energy meter's display should illuminate and begin showing readings.
- Adjust Display: Rotate the display unit to achieve the best viewing angle.

Figure 4.1: The GreenBlue GB620 E Energy Meter plugged into a wall socket, ready for use.
5. Operating Instructions
The GB620 E provides various measurement modes accessible via its two control buttons. The device automatically saves all collected data even in the event of a power outage, thanks to its memory backup feature.
5.1. Display Modes
Use the control buttons (usually labeled "MODE" and "SET" or similar) to cycle through the following display modes:
- Real-time Power (W): Displays the instantaneous power consumption of the connected appliance in Watts.
- Accumulated Energy (kWh): Shows the total energy consumed over time in kilowatt-hours.
- Voltage (V): Displays the current line voltage.
- Current (A): Shows the current drawn by the appliance in Amperes.
- Cost Calculation (€): If configured, displays the estimated cost of electricity consumed.
- Frequency (Hz): Displays the line frequency.

Figure 5.1: The energy meter display showing the total accumulated cost in Euros and kWh.
5.2. Setting Electricity Cost
To enable cost calculation, you may need to set the electricity price per kWh. Refer to your local electricity bill for the current rate. Typically, this involves pressing and holding one of the control buttons (e.g., "SET") and then using the other button to adjust the value. Consult the on-screen prompts or experiment with button combinations if specific instructions are not provided on the device itself.
5.3. Memory Function
The GB620 E features a memory backup function. All accumulated data, including total energy consumption and cost, will be retained even if the device is unplugged or in the event of a power failure. This allows for long-term monitoring without data loss.
6. Maintenance
- Cleaning: Disconnect the energy meter from the power outlet before cleaning. Use a soft, dry cloth to wipe the surface. Do not use liquid cleaners or abrasive materials.
- Storage: When not in use, store the device in a cool, dry place, away from direct sunlight and extreme temperatures.
- Inspection: Periodically inspect the device for any signs of damage, such as cracks in the casing or frayed wires. Do not use if damaged.
7. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Display does not light up. | No power to the wall socket or device is not properly plugged in. | Check the wall socket with another appliance. Ensure the energy meter is fully inserted into the socket. |
| No readings for connected appliance. | Appliance is not turned on or not properly plugged into the meter's output socket. | Ensure the appliance is powered on and securely connected to the energy meter. Check if the appliance itself is functioning. |
| Inaccurate readings. | Device malfunction or incorrect settings (e.g., electricity cost). | Verify electricity cost settings. If issues persist, contact customer support. |
| "ENERGY OVERLOAD" message. | Connected appliance exceeds the maximum rated power (3680W). | Immediately unplug the appliance. Do not connect appliances that exceed 3680W to this meter. |
8. Specifications
| Parameter | Value |
|---|---|
| Model | GB620 E |
| Maximum Load | 3680 W |
| Power Supply | 220-240 V / 50-60Hz, 16 A |
| Voltage Measurement Range | 200 V - 276 V (Accuracy +/- 2%) |
| Current Measurement Range | 0.00 - 20 A (Accuracy +/- 2%) |
| Power Display Range | 0.3 - 3680 W (Accuracy +/- 2%) |
| Consumption Range | 0 - 9999 kWh |
| Meter Dimensions | 5.5 x 5.5 cm |
| Display Dimensions | 5 x 5 cm |
| Protection Degree | IP20 |
| Operating Temperature Range | -10°C to +40°C |
| Operating Humidity Range | 30 - 80% |
| Color | White |
| Memory Backup | Yes (data retained during power outage) |
9. Warranty and Support
For warranty information and technical support, please refer to the documentation provided with your purchase or visit the official GreenBlue website. Keep your proof of purchase for warranty claims.





