Skip to main content
Zoom the image with the mouse

| DX517

Synology DX517 expansion unit for use with DiskStation NAS devices, up to 50TB of additional storage

Free delivery on mainland UK and most EU countries. Check delivery charges to where you are.
  • Hot-swappable design for installation
  • Provides up to 50TB of additional storage
Hurry! Only left

This product is discontinued, for alternatives please see Wisenet NVRs and VMS

Overview of the Synology DX517

This expansion unit from Synology includes five drive bays and provides up to 50TB of additional storage when connected to a Synology DiskStation NAS using the included expansion cable.

The unit’s hot-swappable design enables straightforward installation of hard drives and also helps to reduce costly system downtime during drive replacement. Either end of the supplied expansion cable features an eSATA connector to help ensure a reliable connection and maximum throughput. In addition, the RAID volume of any connected DiskStation unit can be expanded directly without having to reformat any of the existing hard drives - helping to ensure seamless expansion of capacity without any system downtime.

Alternatively, the unit can be used as a dedicated local backup solution for a Synology DiskStation. When created as a separate volume, this expansion unit supports the backup of data to its local hard drives in the case of system failure.

Please note: this expansion unit can be supplied with a choice of up to five 6TB WD Purple hard drives (fitting required). These drives are specifically engineered for video surveillance applications. (Please select storage from the dropdown menu above).

Key features & benefits

  • Expansion unit designed for direct connection to a Synology NAS to provide up to 50TB of additional storage
  • Compatible with a wide range of Synology network attached storage devices and NVR units
  • Supports up to 50TB storage across five drive bays and can be supplied with WD Purple hard drives (fitting required)
  • Straightforward installation and hassle-free maintenance of disks with hot-swappable design
  • Included expansion cable ensures a reliable connection and maximum throughput



  • User’s Guide
  • Accessory pack
  • AC power cord
  • Expansion cable

Optional (please select from the dropdown menu above):

  • Storage
Back To Top

Key technical features for Synology DX517

Expansion Unit
Compatible drive type: 3.5"/2.5" SATA HDD
Drive bays: 5
Maximum internal raw capacity: 50TB (10TB HDD x 5 max.) (Capacity may vary by RAID types) (please select storage from the dropdown menu above)
Hot swappable HDD: yes
RAID management through DSM: yes
Power consumption: max: 29.9W 
System fan: 2 (80 x 80 mm)
eSATA port: 1
Power: 100-240V, AC power adapter included
Dimensions: 157 x 248 x 233 mm
Weight: 3.91kg
Operating temperature: 5°C to 40°C
Warranty: 3 years
We're here to assist you
Find out how we can help, call us on 0151 633 2111