DX525 | Synology Inc.

Expansion Unit DX525

Seamless capacity expansion for Synology DiskStation

Storage expansion without downtime

Easily add five additional drive bays to your Synology DiskStation. The DX525 supports both 2.5" and 3.5" SATA drives and features plug-and-play setup and hot-swap capability for uninterrupted operation during capacity expansion.

Dedicated local backup solution

The Synology DX525 provides a dedicated local backup solution for your Synology DiskStation. When configured as a separate volume, it safeguards data on its local disks in case of system failure.

Online volume expansion

Managed through the host NAS's DiskStation Manager (DSM), the DX525's additional bays are immediately available upon connection. On-the-fly volume expansion ensures uninterrupted service and storage expansion on the host.

Performance backed by Synology drives

Designed for Synology systems, Synology drives deliver consistent performance and unmatched reliability for your deployments.

HDD

Enterprise Series 3.5" SATA

Plus Series 3.5" SATA

SSD

Enterprise Series 2.5" SATA

Synology has you covered

The DX525 is backed by Synology's three-year limited warranty, including technical support and hardware replacement services. Extend your coverage to five years and gain access to premium services that accelerate recovery in the event of a disaster with Extended Warranty Plus.

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Notes:Compatible drives are mandatory. Please consult our compatibility list before purchasing hard drives. For more details, please refer to this article.The warranty period starts from the date of purchase as stated on your purchase receipt. Visit https://www.synology.com/company/legal/warranty for more information.Up to 5 years of warranty are available as an additional bundle with Extended Warranty Plus or Extended Warranty, both 2-year extended warranty service add-ons available in select regions. Check availability for Extended Warranty or Extended Warranty Plus.

Hardware Specifications
Applied Models
Applied Models	Supports creating volumes across different units	DS925+
	Notes	To have better performance, we recommend creating storage volumes physically located within the same NAS or Expansion Unit, rather than creating volumes across your NAS and Expansion Unit.
Storage
Storage	Drive Bays	5
	Drive Type (See all supported drives)	3.5" SATA HDD 2.5" SATA SSD
	Hot Swappable Drive*
	RAID Management through Synology DSM
	Notes	Compatible drives are mandatory. Please consult our compatibility list before purchasing hard drives. For more details, please refer to this article.
External Ports
External Ports	Expansion Port	1
Appearance
Appearance	Size (Height x Width x Depth)	166 mm x 230 mm x 223 mm
	Weight	2.46 kg
Power
Power	Power Recovery	Synchronized with the Synology DiskStation
	Power Supply Unit / Adapter	90 W
	AC Input Power Voltage	100V to 240V AC
	Power Frequency	50/60 Hz, Single Phase
	Power Consumption*	35.37 W (Access) 7.0 W (HDD Hibernation)
	British Thermal Unit	120.69 BTU/hr (Access) 24.02 BTU/hr (HDD Hibernation)
	Notes	For more information on how power consumption is measured, refer to this article.
Temperature
Temperature	Operating Temperature	0°C to 40°C (32°F to 104°F)
	Storage Temperature	-20°C to 60°C (-5°F to 140°F)
	Relative Humidity	5% to 95% RH
Others
Others	System Fan	92 mm x 92 mm x 2 pcs
	Noise Level*	20.4 dB(A)
	Notes	Noise testing was conducted with the Synology system fully installed with Synology SATA HDDs and in an idle state. Two G.R.A.S. Type 40AE microphones are placed at a 1 m distance from the front and rear of the device. Background noise: 16.49-17.51 dB(A); Temperature: 24.25-25.75˚C; Humidity: 58.2-61.8%
Certification
Certification	FCC CE BSMI UKCA EAC VCCI RCM KC BIS
Warranty
Warranty	3-year hardware warranty, extendable to 5 years with EW201 or Extended Warranty Plus
	Notes	Availability varies by region. Before purchasing, please visit the official web pages of EW201/202 and Extended Warranty Plus for a list of eligible regions. The warranty period starts from the purchase date as stated on your purchase receipt. (Learn more)
Environment & Packaging
Environment
Environment	RoHS Compliant
Packaging Content
Packaging Content	Main Unit X 1 Expansion Cable: USB Type-C X1 Accessory Pack X 1 AC Power Adapter X 1 AC Power Cord X 1
Optional Accessories
Optional Accessories	Enterprise Series 3.5" SATA HDD: HAT5300 Series Plus Series 3.5" SATA HDD: HAT3300 Series Enterprise Series 2.5" SATA SSD: SAT5200 Series

Notes: Model specifications are subject to change without prior notice. The figures are based on Synology internal testing. Each performance test is done individually. No other services or applications are processed at the same time. The actual performance may be lower than lab testing figure due to differences in server configuration, deployment, and the number of active operations. If usage requirements exceed the specifications above, please contact our regional partners for professional advice.