3WVHP Dell 550W S4100 S4048T Switches Reverse Airflow Ac Power Supply

Dell 3WVHP 550W AC Power Supply

Wattage and Power Delivery

The nominal rated output of 550 watts provides stable DC power to all switch midplane and line-card systems under typical load. Designed to operate across a broad input range, the 3WVHP supports 100–240VAC input, enabling global deployment without additional transformers. Tight voltage regulation ensures sensitive switching ASICs and management controllers receive consistent power under dynamic traffic conditions.

Reverse Airflow Design

Reverse-airflow (also called rear-to-front airflow) is common in specific Dell chassis where system cooling is engineered to direct intake from the rear of the chassis and exhaust towards the front. The 3WVHP unit is engineered with a fan and vent placement that aligns with reverse-airflow chassis, preserving intended thermal paths and ensuring accurate thermal sensor feedback. Deploying a standard (forward) airflow unit in a reverse-airflow chassis can dramatically change cooling performance; this category emphasizes the correct reverse-airflow orientation to maintain warranty-friendly deployments and safe operating temperatures.

Compatibility with S4100 & S4048T

Physical form factor, connector pinout, mounting latches, and firmware compatibility are all matched to the Dell S4100 and S4048T series switches. The category includes original Dell part numbers and verified cross-reference part numbers where available. Confirming chassis revision and existing power supply model numbers is recommended before purchase to avoid incompatibility related to latch designs or firmware lockouts.

Reliability & Redundancy

Hot-Swap and Field Replaceable

Hot-swap capability is a critical feature for mission-critical networking. The 3WVHP is engineered for safe insertion and removal while the chassis remains operational, minimizing scheduled downtime and enabling faster on-site repairs. Visual indicators (LEDs) for power presence, AC status, and fault conditions simplify diagnostics for technicians during a hot-swap event.

N+1 and Load Sharing

In multi-PSU configurations, the 550W units support N+1 redundancy and dynamic load sharing. Properly distributing load across supplies extends component life and provides automatic failover if a PSU experiences a fault or is removed for maintenance. This category details how to plan power budgets to maintain N+1 redundancy under peak port-loading scenarios.

Electrical & Safety Standards

Certifications and Regulatory Compliance

Products in this category typically meet common international safety and emissions standards such as UL, CE, CB, and FCC Class A. Efficiency and power factor correction (PFC) features reduce wasted energy and minimize harmonic distortion on building power systems. When selecting a unit, check the listing for applicable safety marks to ensure compliance with local regulatory requirements.

Inrush Current and Surge Protection

Inrush limiting and onboard surge protection help safeguard the chassis and site electrical distribution from transient events. For large rack deployments, staggered power-up strategies may be recommended to avoid tripping branch circuit protective devices due to simultaneous inrush.

Fan Assembly and Noise Considerations

Reverse-airflow PSUs include fan assemblies tuned for chassis airflow direction and acoustic performance. Fan speed profiles are usually temperature-sensor-driven; during low-load operation, fans run at reduced speed to minimize noise while preserving headroom for higher-load or elevated ambient conditions.

Form Factor and Mounting

The 3WVHP's mechanical interface is engineered for the S4100 / S4048T rails and extraction paths. Latch mechanisms, alignment rails, and bezel fitment provide tool-less installation for rapid field service. Units are sized and keyed to prevent accidental insertion into incompatible bays.

Safe Hot-Swap Procedure

Always observe ESD precautions and follow these steps: ensure replacement PSU is identical in orientation, visually confirm LED status after insertion, and monitor chassis logs for any error messages. If the chassis reports an unexpected PSU mismatch, consult firmware revision notes — some chassis require matching firmware revisions for full functionality.

Performance & Efficiency

Power Efficiency Ratings

Efficiency metrics including typical conversion efficiency and PFC performance are important for running costs and thermal load. Selecting higher-efficiency units reduces power draw and heat generation, improving cooling efficiency and lowering data center operating expenses. Many units provide efficiency curves that specify performance at 20%, 50%, and 100% load — use these to estimate real-world consumption for average network loads.

Compatibility Matrix

This category consolidates official Dell part numbers used in S4100 and S4048T series documentation, plus manufacturer cross-references for OEM equivalent parts. Buyers should match the chassis service tag and existing PSU model to the cross-reference table to ensure physical and firmware compatibility.

Use Cases and Deployment Scenarios

Enterprise Core and Distribution Switches

In campus and enterprise core deployments where uptime and redundancy are paramount, the 3WVHP supports redundant power architectures and predictable thermal behavior. Its reverse airflow design ensures consistent cooling when deployed in chassis that route airflow towards the front of the rack.

Edge and Remote Sites

For small data centers or remote edge sites, the 550W rating provides an appropriate balance between compact size and sufficient power provisioning for heavily populated port configurations. The universal input voltage range facilitates deployment in varied power infrastructures.

Higher-Wattage Options

For deployments with higher power consumption from optics, PoE injectors, or additional line cards, consider higher-wattage or higher-efficiency PSUs if chassis supports alternate modules. Review the chassis power budget and vendor guidance before substituting wattage classes.