1. Introduction
The TOMZN DDS238 BD is a single-phase two-wire AC active energy meter designed for accurate measurement of electricity consumption in residential, utility, and industrial applications. This meter offers a long service life, high stability, excellent overload capability, and low power loss, all within a compact form factor. It features a clear 6+1 digit LCD display for energy readouts and supports bi-directional total active energy measurement, accumulating reverse active energy into the total. Energy data is reliably retained in a memory chip for over 15 years even after power failure.
Visual indicators include LEDs for power-on status, reverse energy flow, and a pulse LED to show real-time operational status. The meter also provides a passive pulse output with optical coupling isolation for external monitoring systems. It offers flexible installation options, supporting both 35mm DIN rail mounting and direct wall mounting.
2. Safety Information
Warning: To avoid danger of suffocation, keep any plastic packaging away from babies and children. Do not use this packaging in cribs, beds, carriages, or playpens. This packaging is not a toy.
- All operations, including installation and parameter adjustments, must be performed by a qualified electrical professional.
- Do not place the device near flammable materials.
- Ensure adequate ventilation during operation to prevent overheating.
- Disconnect the device from power and store it properly when not in use for extended periods.
3. Specifications
The following table details the technical specifications of the DDS238 BD energy meter:
| Parameter | Value |
|---|---|
| Model | DDS238 BD |
| Number of Poles | Single phase 2 wire |
| Rated Voltage | 220/230V 50/60Hz (0.8~1.2Un) |
| Rated Current | 5(100)A |
| Max Operating Current | 80A - 99A |
| Min Measure Current | 20mA (0.004Ib) |
| Maximum Operating Voltage | 130-300V |
| Frequency | 50Hz or 60Hz ±10% |
| Connection Mode | Direct type |
| Accuracy Class | Class 1 (1%) |
| Measuring Energy Range | 999999.9 kWh |
| Power Consumption | <2W / <10VA |
| Display Type | LCD 6+1 digits |
| Energy Data Retention | >15 years after power off |
| Indicators | Power-on LED, Reverse LED, Pulse LED |
| Pulse Output | Passive pulse, 80±5 ms, optical coupling isolation |
| AC Voltage Withstand | 2000V / 25mA for 60s |
| IP Grade | IP20 |
| Installation | 35mm DIN rail or wall mounting |
| Operating Temperature | -25°C to 55°C |
| Dimensions | 81*45*92 mm |
| DIY Supplies | Electrical |
| Certification | CE |
Note: Other voltage and current options may be available. Custom designs can be requested.
4. Setup and Installation
Installation of the DDS238 BD energy meter should only be performed by a qualified electrical professional to ensure safety and correct functionality.
4.1. Mounting
The meter supports two primary installation methods:
- 35mm DIN Rail Mounting: The meter can be easily clipped onto a standard 35mm DIN rail.
- Wall Mounting: Alternatively, the meter can be directly mounted to a wall using appropriate fasteners through its designated mounting points.
4.2. Wiring Connection
Connect the equipment in accordance with the wiring diagram specifications. Ensure all connections are secure to prevent loosening and overheating. The meter features twin screw terminals designed for steady and safe connections, capable of holding up to 100A power.
The terminals are clearly labeled:
- L input: Live wire input
- L output: Live wire output
- N input: Neutral wire input
- N output: Neutral wire output
5. Operation
Once installed and wired correctly by an electrical professional, the DDS238 BD meter will begin monitoring and recording energy consumption automatically.
5.1. Display and Indicators
The meter features a 6+1 digit LCD display that accurately tracks every kilowatt-hour (kWh). This allows for long-term monitoring and easy viewing of power usage, even for heavy appliances.
The meter includes several LED indicators:
- Power-on LED: Illuminates when the meter is receiving power.
- Reverse LED: Illuminates to indicate reverse active energy flow.
- Pulse LED: Flashes to indicate the meter is actively measuring energy (1600p/kWh).
5.2. Bi-directional Measurement
The DDS238 BD meter is capable of bi-directional measurement, meaning it accurately tracks both imported and exported active energy. Reverse active energy is accumulated into the total active energy, providing a comprehensive overview of energy flow.
5.3. Passive Pulse Output
The meter provides a passive pulse output with optical coupling isolation. This output can be used to connect to external systems for remote monitoring or data logging of energy consumption.
6. Maintenance
The DDS238 BD energy meter is designed for long-term, maintenance-free operation. However, to ensure optimal performance and longevity:
- Keep the meter clean and free from dust and debris. Use a soft, dry cloth for cleaning.
- Do not use abrasive cleaners or solvents.
- Periodically check the wiring connections for any signs of loosening or damage. Any issues should be addressed by a qualified electrician.
- Ensure the operating environment remains within the specified temperature range (-25°C to 55°C) and has adequate ventilation.
7. Troubleshooting
If you encounter any issues with your DDS238 BD energy meter, consider the following basic troubleshooting steps:
- No Display/No Power-on LED: Check the power supply to the meter. Ensure all wiring connections are secure and correct.
- Incorrect Readings: Verify that the wiring is connected according to the diagram. Ensure the meter is installed in the correct phase.
- Pulse LED not flashing: If there is active energy consumption and the pulse LED is not flashing, there might be an internal issue or incorrect wiring.
- Reverse LED constantly on: This indicates continuous reverse energy flow. Verify the direction of current flow in your installation.
For any persistent issues or complex problems, always consult a qualified electrical professional. Do not attempt to repair the meter yourself.
8. User Tips
- Optocoupler Output: The optocoupler output is located on the meter and provides a passive pulse for external monitoring. Refer to the wiring diagram (Figure 6) for its connection points.
- Energy Data Retention: Be assured that your energy consumption data is stored in the meter's memory chip for over 15 years, even during power outages.
- Monitoring Energy Usage: Utilize the clear LCD display to regularly check your energy consumption. This can help identify high-usage periods or appliances.
9. Warranty and Support
This product complies with the following applicable regulations and harmonized standards:
- Low Voltage Directive 2014/35/EU
- Electromagnetic Compatibility Directive 2014/30/EU
- Restriction of the use of certain hazardous substances (RoHS) Directive 2011/65/EU
For specific warranty details, please refer to the purchase documentation or contact your retailer. For technical support, please reach out to the TOMZN customer service or your local distributor.
10. Additional Resources
A detailed user manual in PDF format is available for download. This document provides further in-depth information regarding the installation, operation, and technical aspects of the DDS238 BD meter.
You can access the PDF manual here: DDS238 BD User Manual (PDF)