FireWire: Maximum Number of FireWire Devices

Learn about the number of maximum AC-powered and bus-powered FireWire devices you can use with FireWire capable Macintoch computers.
This article has been archived and is no longer updated by Apple.
FireWire Devices

FireWire capable Macintosh computers support a maximum of 63 powered FireWire devices. You can connect a maximum of 16 FireWire devices in one chain.

Bus-powered FireWire Devices

When connecting multiple bus-powered FireWire devices to a computer, be careful that the total power consumed by the devices isn't more than the computer can provide. If the power draw exceeds the computer's limit, all devices on the FireWire bus may shut down unexpectedly during heavy activity. For example, copying several files from one FireWire drive to another.

If you experience FireWire devices shutting down unexpectedly:

  • Use devices that have their own AC power supply. For example, plug device directly into a power outlet.
  • Plug devices into separate FireWire ports instead of chaining them together.
  • Reduce the number of FireWire devices connected to the computer.
Published Date: Feb 20, 2012