WD Ultrastar DC HC555 3.5" 20TB, 7200 RPM, 512MB, 550 WRL, SAS Hard Drive, Enterprise

The Western Digital Ultrastar DC HC555 is an enterprise-grade hard drive engineered for data center and server environments. It provides 20 TB of storage capacity and utilizes a high-speed SAS interface for robust data connectivity in demanding infrastructures. The drive incorporates HelioSeal technology, which seals the enclosure with helium to reduce internal turbulence, enabling lower power consumption and increased reliability in multi-drive arrays. Integrated Rotational Vibration (RV) sensors help maintain consistent performance under heavy operational load by mitigating external disturbances.

This model operates at a spindle speed of 7200 RPM and is equipped with a 512 MB cache to facilitate efficient data handling and reduce latency. It is built for continuous 24/7 operation, supported by a Mean Time Between Failures (MTBF) rating of 2.5 million hours and a workload limit of 550 TB per year. These specifications are aligned with the requirements of intensive, always-on enterprise applications that depend on long-term data integrity and consistent availability. It is intended for deployment in servers, workstations, and large-scale data centers.

• 20 TB storage capacity
• 3.5-inch form factor
• SAS interface with a 12 Gbit/s transfer rate
• 7200 RPM spindle speed
• 512 MB cache buffer size
• Sequential read and write speeds up to 285 MB/s
• 2.5 million hours Mean Time Between Failures (MTBF)
• Workload rate limit of 550 TB per year
• Supports S.M.A.R.T. monitoring
• Average latency of 4.16 ms
• Idle noise level of 32 dB
• Dimensions of 101.6 mm x 147 mm x 26.1 mm
• Weight of 690 g