QSFP-DD to 2x QSFP56-400G-DAC-2.5M8FT 400G QSFP-DD 8 x 50G PAM4 to 2 x 200G QSFP56 4 x 50G PAM4 Passive Copper Breakout Cable, 2.5m (8ft)
This QSFP-DD to 2x QSFP56-400G-DAC-2.5M8FT compatible cable gives project teams a defined 400G connection in 2.5m (8ft), with QSFP-DD to 2x QSFP56 and Generic host compatibility. Rather than treating all lengths as interchangeable, the page keeps this order code separate and links the other verified lengths for accurate schedules, labels and delivery checks.
OEM Part Number: QSFP-DD to 2x QSFP56-400G-DAC-2.5M8FTHT Part Number: QSFP-DD to 2x QSFP56-400G-DAC-2.5M8FT
Product Highlights
- HT-manufactured DAC assembly in 2.5m (8ft)
- 400G connectivity at 400Gbps
- Interface configuration: QSFP-DD to 2x QSFP56
- Fixed length and part number: 2.5m (8ft), QSFP-DD to 2x QSFP56-400G-DAC-2.5M8FT
- Cable construction: Passive Twinax
- Conductor specification: 28AWG
- Maximum power consumption: 0.1W (QSFP-DD End) 0.1W (QSFP56 Per End)
- Minimum bend radius: 39.5mm
Specifications
| HT Part Number | QSFP-DD to 2x QSFP56-400G-DAC-2.5M8FT |
|---|---|
| Manufacturer | HT |
| Connector Type | QSFP-DD to 2x QSFP56 |
| Max. Data Rate | 400Gbps |
| Media | Copper |
| Cable Type | Passive Twinax |
| Cable Length | 2.5m (8ft) |
| Wire AWG | 28AWG |
| Minimum Bend Radius | 39.5mm |
| Max. Power Consumption | 0.1W (QSFP-DD End) 0.1W (QSFP56 Per End) |
| Jacket Material | PVC |
| Commercial Temperature Range | 0 to 70°C (32 to 158°F) |
| Protocols | IEEE802.3Bj, By, IEEE802.3CD, SFF-8679, SFF-8636 |
| Application | 400G Ethernet |
| Modulation Technology | PAM4 |
Power and Thermal Planning
The rated power consumption is 0.1W (QSFP-DD End) 0.1W (QSFP56 Per End). Include this load in the host-port power and thermal budget, especially in densely populated switches. Maintain front-panel clearance and do not bundle the cable so tightly that it obstructs airflow around the connectors.
Cable Construction and Routing
This assembly uses 28AWG conductors, PVC jacket, minimum bend radius 39.5mm. These mechanical characteristics affect how the cable should be dressed behind the equipment. Avoid sharp edges, excessive ties and repeated tight bends close to the connector boots.
Network and Protocol Considerations
The intended application is 400G Ethernet. Listed interface and protocol references include IEEE802.3Bj, By, IEEE802.3CD, SFF-8679, SFF-8636. Confirm that the host firmware and port configuration support the same operating mode.
Breakout Port Mapping
The QSFP-DD to 2x QSFP56 configuration divides the high-speed interface into multiple lower-speed connections. Verify the upstream lane assignment, downstream port speeds and breakout setting on the host before connecting the assembly. Each branch must attach to the correct remote interface.
Passive Copper Operation
A passive DAC has no separate optical conversion stage. Its low-power, low-latency operation is useful for short equipment links, but the assembly must remain within the length and signaling mode accepted by both hosts.
Length Selection and Installation Planning
The 2.5m (8ft) version is useful when a two-metre run would leave insufficient working slack. Before installation, check the complete horizontal and vertical path so that QSFP-DD to 2x QSFP56-400G-DAC-2.5M8FT reaches both ports without tension at either connector.
Position Within the Length Range
QSFP-DD to 2x QSFP56-400G-DAC-2.5M8FT occupies the middle of this family between QSFP-DD to 2x QSFP56-400G-DAC-2M7FT at 2m (7ft) and QSFP-DD to 2x QSFP56-400G-DAC-3M10FT at 3m (10ft). It adds 0.5m over the shorter option for extra routing clearance, while the next longer version adds another 0.5m. Measure the managed path and choose this version when its reach is sufficient without creating the slack associated with the longer assembly.
Project Documentation and Cable Identification
Large deployments are easier to audit when the order code, physical length and endpoint record agree. Keep the OEM reference in the compatibility document and use the HT part number on the packing list. Where several lengths arrive together, labels and carton groups can be arranged by rack or port plan so installers do not have to identify cables by appearance alone. For this assembly, the listed conductor specification is 28AWG; the minimum bend radius is 39.5mm; the stated power consumption is 0.1W (QSFP-DD End) 0.1W (QSFP56 Per End); the jacket material is PVC.
Generic Compatibility and Factory Testing
Factory verification links the compatibility identity to the exact physical assembly described on this page. Identification, connector condition and live link behavior are checked before packing. Customers can submit equipment and firmware details with the project documentation for a more specific pre-order compatibility review. Where supported by the host, link stability and diagnostic indications are reviewed together with the established link.
Frequently Asked Questions
Is this an original equipment manufacturer cable?
No. It is manufactured by HT under our own manufacturer identity.
What details assist a compatibility review?
Provide the equipment manufacturer, model, port type, hardware revision and software release, together with the OEM reference, required length and quantity.
How should an unused assembly be stored?
Protect both connector ends, keep the cable in a loose bend-safe coil and retain its part-number label so the length and compatibility identity remain traceable.
Can different brands be connected with the same assembly?
Only where both hosts explicitly support the complete interface and compatibility arrangement. Document each end and select the appropriate brand-specific product when required.
Ordering Information
Use the listed HT part number for ordering and retain the OEM reference as the host-compatibility cross-reference. Send quantities by length, along with any rack-based packing or label instructions. If the project has mixed equipment, include the host model for each group rather than relying only on the aggregate cable rate. Quantity and any labeling instructions should be attached specifically to QSFP-DD to 2x QSFP56-400G-DAC-2.5M8FT.
Shipping and Lead Time
Standard configurations normally ship within one to three working days, while production quantities are confirmed with the order. Delivery can be arranged by courier, air freight or sea freight, and goods may instead be handed to an appointed forwarder or shipped on the customer’s courier account.
Quality Assurance and Packaging
Inspection and link testing are completed before the cable enters its protective packaging. Project orders can be packed and labelled by length, rack or customer reference, with packing documentation that makes received quantities straightforward to reconcile against the installation schedule. Standard protective packing is used by default, with project documentation arranged when requested.
