LaCie 2big Dock Thunderbolt 3 User Manual
LaCie 2big Dock Thunderbolt 3 User Manual

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Daisy Chain and Power Delivery

Use the two Thunderbolt 3 ports on the LaCie 2big Dock for:

  • Direct connection to a computer that is compatible with Thunderbolt 3 technology.
  • Daisy chaining with devices and displays that are compatible with Thunderbolt 3 technology.

Daisy chain Thunderbolt 3 devices

Thunderbolt 3 is an update of Thunderbolt 2 technology. While Thunderbolt 2 technology continues to provide impressive transfer rates up to 20Gb/s bi-directional, Thunderbolt 3 offers improved performance with a potential transfer rate of up to 40Gb/s bidirectional. Thunderbolt 3 technology also gives you greater flexibility when using video and data, assigning greater throughput to the stream that carries the heavier load. You must have a computer that supports Thunderbolt 3 to take advantage of the updates in performance and the intelligent sharing of bandwidth.

Similar to Thunderbolt 2 technology, a single Thunderbolt 3 daisy chain can have up to seven devices, including the computer. For example, you can daisy chain five LaCie 2big Dock enclosures on the same line with a display.

How to daisy chain

Connect the cable to one of the interface ports on the back of LaCie 2big Dock and to your computer. The additional port on your device can be used to daisy chain compatible Thunderbolt 3 peripherals, such as hard drives and monitors. If you have another Thunderbolt 3 storage device, make certain to connect it to the daisy chain before adding compatible displays or USB 3.1 (USB-C) devices. See below for an example of the order of devices in a Thunderbolt 3 daisy chain.

  1. Computer with a Thunderbolt 3 port
  2. LaCie 2big Dock Thunderbolt 3 (Thunderbolt 3 ports)
  3. LaCie d2 Thunderbolt 3 (Thunderbolt 3 ports)
  4. LaCie Bolt 3 (Thunderbolt 3 ports)
  5. LaCie Porsche Desktop (USB 3.1 (USB-C) port)

USB 3.1 (USB-C) devices can terminate a Thunderbolt 3 daisy chain and should always be the last device. It must be connected to the secondary Thunderbolt 3 port on the preceding device. (The USB 3.1 device will not be recognized if connected to the preceding device’s USB-C port.)

  Note on the USB 3.1 (USB-C) port: USB 3.1 does not support daisy chaining devices. Therefore, a USB 3.1 (USB-C) port on your computer cannot be used to daisy chain devices.
  Important cable info: When connecting your enclosure to a computer or compatible devices, use cables specifically constructed to support Thunderbolt 3.
  Important info: To reach Thunderbolt 3 transfer rates up to 40Gb/s bidirectional, LaCie 2big Dock Thunderbolt 3 must be connected to a computer that supports Thunderbolt 3 technology.

Daisy chain: power-saving mode

You can daisy chain Thunderbolt 3 devices even when the LaCie 2big Dock hard drives are spun down. Power-saving mode is initiated by applying a short push on the power button (see Operation). The status LED blinks slowly, indicating that the device is in power-saving mode.

Power delivery

You can connect compatible devices that support charging via USB-C to the Thunderbolt 3 ports or the USB 3.1 port. A Thunderbolt 3 port on LaCie 2big Dock outputs up to 15W of power, while the USB 3.1 port provides up to 27W of power. The LaCie 2big Dock must receive power via its power cable in order to deliver power to compatible devices.

  Note: The power delivered may not be sufficient to charge a laptop.
  Important info: LaCie is not responsible for devices that experience harm, damage, or malfunction when connected to LaCie 2big Dock.