Arista Networks CAB-Q-S-3M Compatible 40G QSFP+ to 4 x 10G SFP+ Passive Copper Breakout Cable, 3m (10ft)
For buyers working from an equipment parts list, CAB-Q-S-3M identifies more than a connector style. It refers here to a 3m (10ft) DAC cable for Arista Networks hosts, supporting 40G operation with QSFP+ to 4 SFP+. The sections below separate the OEM cross-reference, physical specification and HT factory checks for straightforward purchasing review.
OEM Part Number: CAB-Q-S-3MHT Part Number: CAB-Q-S-3M
Product Highlights
- Compatible alternative to Arista Networks CAB-Q-S-3M
- 40G connectivity at 40Gbps
- Interface configuration: QSFP+ to 4 SFP+
- Fixed length and part number: 3m (10ft), CAB-Q-S-3M
- Conductor specification: 30AWG
- Minimum bend radius: 21mm
Specifications
| HT Part Number | CAB-Q-S-3M |
|---|---|
| Arista Networks Compatible | CAB-Q-S-3M |
| Manufacturer | HT |
| Connector Type | QSFP+ to 4 SFP+ |
| Max Data Rate | 40Gbps |
| Minimum Bend Radius | 21mm |
| Wire AWG | 30AWG |
| Cable Length | 3m (9.84ft) |
| Jacket Material | PVC (OFNR) |
| Temperature | 0 to 70°C (32 to 158°F) |
| Protocols | SFF-8436, SFF-8431 and QSFP+ MSA |
Cable Construction and Routing
This assembly uses 30AWG conductors, PVC (OFNR) jacket, minimum bend radius 21mm. 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 determined by the host interface and protocol support. Listed interface and protocol references include SFF-8436, SFF-8431 and QSFP+ MSA. Confirm that the host firmware and port configuration support the same operating mode.
Breakout Port Mapping
The QSFP+ to 4 SFP+ 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
At 3m (10ft), this assembly can bridge non-aligned ports or adjacent racks while remaining a single direct-attach link. Support longer horizontal runs with suitable cable management and preserve space for cooling and future maintenance.
Position Within the Length Range
CAB-Q-S-3M occupies the middle of this family between CAB-Q-S-2M at 2m (7ft) and CAB-Q-S-4M at 4m (13ft). It adds 1m over the shorter option for extra routing clearance, while the next longer version adds another 1m. Measure the managed path and choose this version when its reach is sufficient without creating the slack associated with the longer assembly.
Procurement and Port-Mapping Review
A useful purchase order should identify the host platform, the expected OEM code and the exact cable length as separate pieces of information. This prevents a physically similar assembly from being substituted when the port identification or reach is different. For mixed-length installations, prepare one order line per part number and reconcile each delivered cable with its intended pair of ports. For this assembly, the listed conductor specification is 30AWG; the minimum bend radius is 21mm; the jacket material is PVC (OFNR).
Arista Networks Compatibility and Factory Testing
Our procurement-oriented compatibility check begins with the OEM reference and ends with a live host link. We record the physical length separately from the identification configuration, so the cable supplied for this page remains the stated version rather than a generic length substitute. The check includes link stability and diagnostic indications, followed by a final inspection of both ends.
Ordering Information
For a clear bill of materials, quote the OEM reference, HT part number, length and quantity on the same line. Add the switch or server model and software release when a pre-order review is required; project labels can repeat those details for receiving and installation teams. Keep CAB-Q-S-3M associated with 3m (10ft) throughout the order and receiving record.
Quality Assurance and Packaging
Before packing, the assembly is checked for connector condition, identification and link operation. Cables for multi-line orders can be labelled and grouped by part number, making it easier to match each length to the procurement record without opening every protective bag. Standard protective packing is used by default, with project documentation arranged when requested.
Frequently Asked Questions
Is this an original Arista Networks cable?
No. It is an HT-manufactured compatible alternative for equipment that specifies Arista Networks CAB-Q-S-3M.
Will any matching connector operate at the same speed?
Not necessarily. Both hosts must support the stated rate, identification, lane mapping and any required breakout configuration; mechanical compatibility alone is insufficient.
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.
Shipping and Lead Time
Standard configurations normally ship within one to three working days, while production quantities are confirmed with the order. International express, air cargo and sea freight can be selected according to destination and carton volume; customer courier accounts and nominated forwarders are also accepted.