1. Introduction
The Alinco DT-831D is a compact and highly efficient switching DC-DC converter designed to provide a stable 13.8V DC output from a 24V DC input source. Its advanced switching system ensures high efficiency and stable performance, making it suitable for various applications requiring reliable power conversion. This manual provides essential information for the safe and effective use of your DT-831D converter.
Image 1.1: Front view of the Alinco DT-831D DC-DC Converter. The image displays the digital meter showing voltage and current, the power switch, noise offset knob, and various output terminals. Labels visible include "ALINCO SWITCHING DC-DC CONVERTER DT-831D", "24V>13.8V", "NOISE OFFSET", "POWER ON/OFF", "OUTPUT MAX 5A", "PROTECT OVER", and "INPUT VOLTAGE". A cigarette lighter socket is also visible on the left, labeled "MAX 10A".
2. Safety Information
- Ensure the input voltage is within the specified range of DC 21-28V. Incorrect input voltage can damage the unit.
- Do not exceed the maximum output current ratings for any terminal to prevent overload.
- The unit is equipped with protection circuits for output overcurrent, overvoltage, short circuit, and heat. In case of an abnormality, the unit may shut down or limit current.
- Ensure proper ventilation around the unit. The thermo-sensitive fan requires clear airflow to prevent overheating.
- Do not open the casing of the converter. Refer servicing to qualified personnel.
- Keep the unit away from moisture, dust, and extreme temperatures.
3. Product Features
- Compact Switching System: Designed for space efficiency and high performance.
- High Efficiency: Provides up to 30A continuous output with high stability.
- Advanced Protection: Features thermo-sensitive fan, overcurrent (32A operating point), overvoltage (relay shut-off), short circuit, and heat protection.
- Simplified Wiring: Utilizes a 2-wire input system for easier installation compared to traditional 3-wire models.
- Digital Meter: Clear digital display indicates input voltage (24V), output voltage (13.8V), and load current levels.
- Accessory Terminals: Includes various output terminals for different power requirements (main, cigarette lighter, push terminals, memory backup).
- Noise Offset Volume: Adjustable control to minimize switching noise, particularly useful when operating sensitive radio equipment.
- RoHS Compliant: Adheres to environmental standards.
4. Setup
4.1 Input Power Connection
- Ensure the power source is a DC 21-28V supply.
- Connect the positive (+) wire from your 24V DC source to the positive input terminal of the DT-831D.
- Connect the negative (-) wire from your 24V DC source to the negative input terminal of the DT-831D.
- Verify all connections are secure and correctly polarized.
4.2 Output Device Connection
The DT-831D offers multiple output terminals for various devices. Select the appropriate terminal based on the power requirements of your device.
- Main Terminals: Designed for high-current devices, supporting up to 30A.
- Cigarette Lighter Socket: Provides up to 10A for compatible accessories.
- Push Terminals (2 systems): Each system supports up to 5A for lower-power devices.
- Memory Backup Terminal: Supports 15A when on, and 1A when off, for devices requiring continuous low-power supply.
Connect your 13.8V DC devices to the respective output terminals, ensuring correct polarity (+ to + and - to -).
5. Operating Instructions
5.1 Powering On/Off
- To power on the converter, press the POWER ON switch to the 'ON' position. The digital meter will illuminate.
- To power off the converter, press the POWER ON switch to the 'OFF' position.
5.2 Digital Meter Display
The digital meter provides real-time information:
- Top Display: Shows the output voltage (fixed at 13.8V).
- Bottom Display: Shows the current load in Amperes (A).
- Input Voltage Indicator: A light indicates the 24V input.
- Load Level Indicators: 'HI' and 'LO' indicators may show the relative load level.
5.3 Noise Offset Adjustment
The NOISE OFFSET knob allows you to adjust the switching frequency to minimize interference with sensitive radio equipment. Rotate the knob to find the setting that provides the least noise for your specific setup.
6. Maintenance
- Cleaning: Periodically clean the exterior of the unit with a soft, dry cloth. Do not use liquid cleaners or solvents.
- Ventilation: Ensure the cooling fins and fan vents are free from dust and obstructions to maintain proper airflow.
- Fuse Replacement: The unit uses a 30A fuse. If the unit fails to power on or provide output, check and replace the fuse if necessary. Always replace with a fuse of the same rating.
7. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| No power/No display | Power switch off, input power disconnected, blown fuse. | Turn power switch on, check input connections, replace 30A fuse. |
| No output voltage | Overload protection activated, output short circuit, internal fault. | Reduce load, check output wiring for short circuits, power cycle the unit. If problem persists, seek service. |
| Overheating | Insufficient ventilation, excessive load. | Ensure clear airflow around the unit, reduce connected load. |
| Excessive noise/interference | Switching frequency interference. | Adjust the NOISE OFFSET knob. |
8. Specifications
| Parameter | Value |
|---|---|
| Input Voltage | DC 21 - 28 V (Rated 24.0 V) |
| Output Voltage | DC 13.8 V (fixed) |
| Output Current | 30 A (continuous) |
| Output Voltage Fluctuation Rate | Less than 2% |
| Output Overcurrent Protection | Automatic current limiting (operating point 32 A) |
| Output Overvoltage Protection | Power shut-off by relay |
| Short Circuit Protection | Yes |
| Heat Protection | Air cooled by thermo-sensitive fan |
| Fuse Used | 30 A |
| Main Terminal Max Load | 30 A |
| Cigarette Lighter Socket Max Load | 10 A |
| Push Terminals (2 systems) Max Load | 5 A each |
| Memory Backup Terminal Max Load | 15 A (on), 1 A (off) |
| Digital Meter Accuracy (Current) | ±2 A (above 5 A), ±0.5 A (less than 5 A) |
| Dimensions (W x H x D) | 175 x 67 x 175 mm (6.9 x 2.6 x 6.9 inches, without protruding items) |
| Weight | Approx. 2.1 kg (4.4 lbs) |
| Environmental Compliance | RoHS compliant |
9. Warranty and Support
For warranty information and technical support, please refer to the documentation provided with your purchase or contact your authorized Alinco dealer. Keep your proof of purchase for warranty claims.
