1. Introduction
The TERRAMASTER TD2 Thunderbolt 3 is a professional-grade 2-bay external hard drive enclosure designed for high-speed data storage and management. It supports 3.5-inch and 2.5-inch SATA HDDs and 2.5-inch SATA SSDs, offering flexible RAID configurations (RAID 0, RAID 1, JBOD, SINGLE) to meet various performance and data protection needs. With two 40Gbps Thunderbolt 3 interfaces, it provides rapid data transfer speeds and supports daisy-chaining of up to six devices, as well as multi-screen display capabilities.
2. Package Contents
- TERRAMASTER TD2 Thunderbolt 3 Enclosure
- Power Adapter
- Thunderbolt 3 Cable
- Accessory Kit (screws, screwdriver)
- Quick Installation Guide
3. Product Overview
3.1 Front Panel

The front panel features two drive bays for hard drive installation. On the left side, there are LED indicators for HDD 1, HDD 2, and Power, providing status information for each drive and the device's operational state. A power button is located below the indicators.
3.2 Rear Panel

The rear panel includes a fan for heat dispersion, a RAID mode switch with a reset button, a Mini DisplayPort 1.4, two Thunderbolt 3 (USB-C) interfaces (one for PC connection, one for daisy-chaining), and a DC 12V power input port.
4. Setup
4.1 Drive Installation
- Ensure the enclosure is powered off and disconnected from your computer.
- Gently pull the drive trays out from the front of the enclosure.
- For 3.5-inch HDDs, align the screw holes on the drive with those on the tray and secure with the provided screws. For 2.5-inch HDDs/SSDs, use the appropriate mounting holes and screws.
- Slide the populated drive trays back into the enclosure until they click into place.
4.2 RAID Configuration

The TD2 Thunderbolt 3 supports hardware RAID modes: RAID 0, RAID 1, JBOD, and SINGLE. Always back up your data before changing RAID modes, as this will erase all data on the drives.
- RAID 0 (Striping): Combines drives for maximum performance and capacity, but offers no data redundancy.
- RAID 1 (Mirroring): Duplicates data across drives for data redundancy. Capacity is limited to the smallest drive.
- JBOD (Just a Bunch Of Disks): Treats drives as independent volumes.
- SINGLE: Each drive is recognized as a separate volume.
To configure RAID:
- With the enclosure powered off, use a small tool (like a paperclip) to rotate the RAID mode switch on the rear panel to your desired setting.
- Press and hold the reset button next to the RAID switch for approximately 5 seconds until the device restarts.
- Connect the enclosure to your computer and initialize/format the drives as required by your operating system.
4.3 Connecting to Your Computer
Use the provided Thunderbolt 3 cable to connect one of the Thunderbolt 3 ports on the enclosure (labeled 'PC') to a Thunderbolt 3 port on your computer. Ensure your computer's operating system (Linux, Mac, Windows) has the necessary Thunderbolt 3 drivers installed.
5. Operating
5.1 Power On/Off
Press the power button on the front panel to turn the device on. The power LED will illuminate. To power off, press and hold the power button until the device shuts down.
5.2 Data Transfer

The TD2 Thunderbolt 3 offers reading speeds up to 760MB/s (with SSHD in RAID 0). Once connected and configured, the enclosure will appear as a storage device on your computer, allowing you to drag and drop files or use it with your preferred applications.
5.3 Multi-Screen Display

Capitalizing on the Thunderbolt 3 and Mini DisplayPort interfaces, the TD2 Thunderbolt 3 supports multi-screen display with up to three screens. Connect your primary display to your computer, and then connect additional monitors to the Mini DisplayPort and the secondary Thunderbolt 3 port on the TD2 enclosure.
5.4 Daisy-Chaining

The TD2 Thunderbolt 3 allows you to daisy-chain up to six devices. Connect the first TD2 to your computer, then connect the second TD2 to the available Thunderbolt 3 port on the first TD2, and so on. This expands your storage and connectivity options.
5.5 Power Delivery
The Thunderbolt 3 connection provides up to 15W of power delivery to recharge compatible laptops (Mac only, Windows not supported).
6. Maintenance
6.1 Heat Management
The aluminum-alloy shell and 80mm fan ensure efficient heat dispersion, maintaining optimal operating temperatures for your drives. Ensure the fan vents on the rear panel are not obstructed to allow for proper airflow.
6.2 Drive Replacement
In RAID 1, JBOD, or SINGLE modes, individual drives can be replaced. For RAID 1, if a drive fails, replace it with a new drive of equal or greater capacity. The system should automatically begin rebuilding the array. Consult the TERRAMASTER support website for detailed instructions on drive replacement and RAID rebuilding procedures.
7. Troubleshooting
- Device not recognized: Ensure the Thunderbolt 3 cable is securely connected to both the enclosure and your computer. Verify that your computer has the latest Thunderbolt 3 drivers installed. Try connecting to a different Thunderbolt 3 port or using a different cable.
- Drives not appearing: After initial setup or changing RAID modes, drives may need to be initialized and formatted through your operating system's Disk Management utility (Windows) or Disk Utility (macOS).
- Slow transfer speeds: Ensure you are using a certified Thunderbolt 3 cable. Check your RAID configuration; RAID 0 offers the highest speeds, while RAID 1 prioritizes data redundancy. The performance of your drives (HDD vs. SSD) also impacts speed.
- RAID rebuild issues: If a drive in a RAID 1 array fails and is replaced, ensure the new drive is healthy and of sufficient capacity. If the rebuild does not start automatically, consult the TERRAMASTER support documentation for manual rebuild procedures.
- Overheating: Ensure the enclosure's fan vents are clear of obstructions. Operate the device in a well-ventilated area.
8. Specifications
| Feature | Detail |
|---|---|
| Model | TD2 Thunderbolt 3 |
| Material | Aluminum |
| Drive Bays | 2 |
| Compatible Drives | 3.5" and 2.5" SATA HDD, 2.5" SATA SSD |
| RAID Modes | RAID 0, RAID 1, JBOD, SINGLE |
| Interface | 2 x Thunderbolt 3 (40Gbps), 1 x Mini DisplayPort 1.4 |
| Max Storage Capacity | Up to 40TB (20TB x 2, in RAID 0) |
| Data Transfer Rate | Up to 760MB/s (with SSHD in RAID 0) |
| Power Delivery | Up to 15W (Mac only) |
| Cooling | 80mm Fan |
| Compatible OS | Linux, Mac, Windows |
| Product Dimensions (LxWxH) | 8.94 x 5.24 x 4.79 inches |
| Item Weight | 3.08 pounds |
9. Warranty and Support
TERRAMASTER products are covered by a limited warranty. For detailed warranty information, technical support, and additional resources, please visit the official TERRAMASTER website or their Amazon store page.
Official TERRAMASTER Store: Visit TERRAMASTER Store