QSFP-DD to QSFP-DD-400G-DAC-0.5M2FT 400G QSFP-DD 8 x 50G PAM4 Passive Copper Twinax Cable, 0.5m (2ft)

This page covers one precise cable-schedule item: Generic QSFP-DD to QSFP-DD-400G-DAC-0.5M2FT in 0.5m (2ft), supporting 400G operation through QSFP-DD to QSFP-DD. The complete DAC assembly is identified separately from other lengths and includes verified specifications, change-control-friendly ordering details and live-link factory checks.
OEM Part Number: QSFP-DD to QSFP-DD-400G-DAC-0.5M2FTHT Part Number: QSFP-DD to QSFP-DD-400G-DAC-0.5M2FT
Product Highlights
- HT-manufactured DAC assembly in 0.5m (2ft)
- 400G connectivity at 400Gbps
- Interface configuration: QSFP-DD to QSFP-DD
- Fixed length and part number: 0.5m (2ft), QSFP-DD to QSFP-DD-400G-DAC-0.5M2FT
- Cable construction: Passive Twinax
- Conductor specification: 30AWG
- Maximum power consumption: 0.1W Per End
- Minimum bend radius: 33mm
Specifications
| HT Part Number | QSFP-DD to QSFP-DD-400G-DAC-0.5M2FT |
|---|---|
| Manufacturer | HT |
| Form Factor | QSFP-DD to QSFP-DD |
| Max. Data Rate | 400Gbps |
| Media | Copper |
| Cable Type | Passive Twinax |
| Cable Length | 0.5m (2ft) |
| Wire AWG | 30AWG |
| Minimum Bend Radius | 33mm |
| Max. Power Consumption | 0.1W Per End |
| Jacket Material | PET (OFNR) |
| Commercial Temperature Range | 0 to 70°C (32 to 158°F) |
| Modulation Format | 8x 50Gbps PAM4 |
| Application | 400G Ethernet |
| Protocols | IEEE 802.3cd, QSFP-DD MSA, CMIS 4.0 |
Signal and Lane Configuration
The listed modulation format is 8x 50Gbps PAM4. Both host interfaces must be configured for the same aggregate rate and lane arrangement. A connector that fits mechanically does not by itself guarantee that the remote port supports this encoding or breakout mode.
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 0.5m (2ft) length is suited to closely aligned ports where excessive slack would obstruct airflow or complicate dressing. Measure the actual port-to-port path before choosing QSFP-DD to QSFP-DD-400G-DAC-0.5M2FT; even a short assembly must retain the specified bend radius and should never be pulled tight behind the equipment.
Position Within the Length Range
QSFP-DD to QSFP-DD-400G-DAC-0.5M2FT is the shortest of 6 verified length options in this family. It is the preferred choice when the port positions are close and cable slack must be kept to a minimum. The next option is QSFP-DD to QSFP-DD-400G-DAC-1M3FT at 1m (3ft), adding 0.5m for a less direct routing path; selecting it unnecessarily would leave more cable to dress.
Structured Pathways and Serviceability
Treat the direct-attach assembly as part of the permanent pathway plan even when the link is expected to be temporary. Follow the intended horizontal and vertical managers, maintain the specified bend radius and leave service access around both ports. A small, supported service allowance is preferable to excess slack concealed inside a rack or placed under cable-tie pressure. For this assembly, the listed conductor specification is 30AWG; the minimum bend radius is 33mm; the stated power consumption is 0.1W Per End; the jacket material is PET (OFNR).
Power and Thermal Planning
The rated power consumption is 0.1W 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 30AWG conductors, PET (OFNR) jacket, minimum bend radius 33mm. 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 IEEE 802.3cd, QSFP-DD MSA, CMIS 4.0. Confirm that the host firmware and port configuration support the same operating mode.
Ordering Information
Include the part number, fixed length, quantity and required pathway or rack grouping in the order information. The host model and firmware release are useful for change-controlled deployments. Different lengths should remain separate order lines so delivered labels and packing records agree with the pathway plan. Keep QSFP-DD to QSFP-DD-400G-DAC-0.5M2FT associated with 0.5m (2ft) throughout the order and receiving record.
Generic Compatibility and Factory Testing
Verification covers the physical connectors, expected host identity and an operating link with available diagnostic indications. We distinguish this complete check from a simple continuity test. Platform model and software release can be reviewed in advance where the installation has strict documentation or change-control requirements. Where supported by the host, link stability and diagnostic indications are reviewed together with the established link.
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
After connector inspection and link verification, the assembly is coiled without tight bends and packed with end protection. Labels can cross-reference the customer cable schedule, OEM part number and length. This supports both receiving checks and later moves, adds or changes. Volume orders can include customer references on the labels and carton list.
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.
QSFP-DD to QSFP-DD-400G-DAC-0.5M2FT