Vertiv Rpdu Rack Transfer Switch Monitored Outlet Level 20A 120V 1.9KW Horizontal - VA6N21A1

Vertiv VA6N21A1 Monitored Outlet-Level Rack Transfer Switch PDU

Overview

The Vertiv VA6N21A1 is a horizontal 0U rack-mount transfer switch PDU delivering 20A at 120V (1.9kW) with monitored outlet-level visibility across six NEMA 5-20R receptacles. Designed for single-phase deployments where both redundant power path management and granular per-outlet monitoring matter, the VA6N21A1 fits cleanly into dense 1U rack environments without consuming valuable rack units thanks to its horizontal 0U form factor. The NEMA L5-20P twist-lock input plug and 3-meter cable provide practical reach to a dedicated 20A circuit — the right combination for IT closets, network racks, and edge compute cabinets where source redundancy is non-negotiable.

Vertiv's Vertiv power distribution and infrastructure products cover the full range of data center and edge power needs. The VA6N21A1 sits within the monitored rack PDU segment — a step above basic metered PDUs because it adds transfer switching, meaning a failover path exists at the outlet group level rather than just at the panel.

Key Features

• Outlet-Level Monitoring (Current, Power, Voltage): Real-time per-outlet current, power, and voltage readings let you catch an overloaded circuit before it trips a breaker. In a mixed-load rack with servers, switches, and storage, knowing exactly which device is drawing what eliminates guesswork during capacity planning or a fault event.
• Six NEMA 5-20R Outlets at 20A/120V: Six outlets across a single 20A feed keeps the math simple — a 16A safe-operating ceiling (80% derating) across the strip. Each outlet accepts standard 5-20 plugs used on most 1U servers and networking gear, so no adapters needed for typical North American rackmount equipment.
• LCD Display: The onboard LCD surfaces load readings at a glance without requiring a laptop or network access. Useful during initial commissioning or when troubleshooting in a cold aisle where pulling up a browser is impractical.
• SNMP v1/v2c/v3 + Full Protocol Stack: The VA6N21A1 supports SNMP v3 (encrypted, authenticated), HTTPS, SSH, RADIUS, TACACS+, and LDAP over both IPv4 and IPv6 — a protocol set that satisfies most enterprise security policies without requiring a separate management appliance. Syslog and SMTP mean alarms route to your existing logging and alerting infrastructure without custom integration work.
• Modbus TCP: Modbus TCP support opens the unit to BMS (Building Management System) and DCIM integration in facilities that already manage power and environmental data through industrial protocols. Not a common feature at this price tier — useful if you're running a unified facilities + IT monitoring platform.
• NEMA L5-20P Twist-Lock Input, 3m Cable: The locking input plug prevents accidental disconnection in high-vibration or busy-hands environments. The 3-meter cord provides genuine routing flexibility rather than forcing the PDU directly adjacent to the power panel.
• Dual Connectivity — Ethernet RJ-45 + USB + Serial: A dedicated RJ-45 Ethernet port handles primary network management. The USB and serial ports support out-of-band console access and firmware updates, preserving management access even if the network path is unavailable.
• IPv6 Native Support: Networks transitioning away from IPv4 or running dual-stack can manage the VA6N21A1 natively without a proxy or protocol translation layer.

Integration & Compatibility

The VA6N21A1 integrates with DCIM and monitoring platforms via SNMP-based network management using v1, v2c, or v3 — the v3 variant adds authentication and encryption, satisfying security requirements that block v1/v2c in hardened environments. RADIUS and TACACS+ integration means user authentication ties to your existing AAA infrastructure rather than local accounts. NTP synchronization keeps event timestamps accurate across Syslog and SMTP alert records. For facilities teams running BMS or DCIM platforms with Modbus TCP support, the VA6N21A1 can feed outlet-level power data directly into broader energy management dashboards — a meaningful advantage over PDUs limited to SNMP-only reporting. Pair with a compatible UPS system on the input feed to complete the redundant power architecture; the transfer switch function is most effective when both source paths are independently protected.

Frequently Asked Questions

Q: What input plug does the VA6N21A1 use, and what circuit does it require?

A: The VA6N21A1 uses a NEMA L5-20P twist-lock plug and requires a dedicated 20A, 120V single-phase circuit. The 3-meter input cord provides flexibility for routing to the panel.

Q: Does the VA6N21A1 support SNMP v3 for encrypted management?

A: Yes. The unit supports SNMP v1, v2c, and v3. SNMP v3 adds authentication and encryption, making it suitable for environments with stricter network security policies that prohibit unencrypted SNMP v1/v2c traffic.

Q: Can the VA6N21A1 integrate with RADIUS or TACACS+ for user authentication?

A: Yes. Both RADIUS and TACACS+ are listed in the supported network protocol stack, allowing administrator authentication to route through your existing AAA infrastructure instead of relying solely on local accounts.

Q: How many outlets does the VA6N21A1 provide, and what type are they?

A: The VA6N21A1 provides six NEMA 5-20R outlets. These accept standard North American 5-20 plugs used on most 1U rackmount servers, switches, and storage devices.

Q: Does the VA6N21A1 support Modbus TCP for BMS or DCIM integration?

A: Yes. Modbus TCP is included in the supported protocol list, enabling integration with Building Management Systems and DCIM platforms that use industrial Modbus-based data collection alongside or instead of SNMP.

Q: What is the 0U horizontal form factor, and how does it mount in a rack?

A: 0U means the unit mounts horizontally in the rack without consuming a numbered rack unit slot — typically along the side channel or in a dedicated PDU mounting position. This preserves all front-facing 1U slots for active equipment.

Marty Allison

The VA6N21A1 is a well-specified monitored transfer switch PDU for integrators who need outlet-level power visibility and source redundancy in a single horizontal 0U unit. The protocol stack here — SNMP v3, RADIUS, TACACS+, Modbus TCP, Syslog, SMTP — is broader than what you typically see at the 20A/6-outlet tier, and it matters when you're deploying into environments with formal change management or security auditing requirements.

Technical Highlights:

• SNMP v3 with RADIUS/TACACS+: Encrypted SNMP v3 plus AAA authentication via RADIUS or TACACS+ means this PDU can actually pass a network security review in regulated environments — most entry-level monitored PDUs stop at SNMP v2c with local credentials only.
• Modbus TCP: Modbus TCP support is a genuine differentiator for mixed IT/OT environments; it lets the VA6N21A1 feed per-outlet watt and amp readings directly into a BMS or DCIM platform without a protocol bridge.
• 20A/120V with NEMA L5-20P Twist-Lock Input: The locking L5-20P plug on a 3-meter cord is the right specification for a dedicated 20A circuit — no wobble under cable management pressure, and the cord length gives you real routing options rather than forcing the PDU to sit directly below the breaker panel.

Deployment Considerations:

• At 20A/120V with six outlets, apply the 80% continuous load rule — plan for no more than 16A aggregate draw across all six NEMA 5-20R receptacles to avoid nuisance trips on the upstream breaker.
• The unit requires 100-120V input only; this is not a dual-voltage PDU. Verify your facility's panel delivers 120V — not 208V single-phase — before ordering, especially in newer data centers where 208V branch circuits are increasingly common even in smaller deployments.

This PDU fits cleanly in a network edge cabinet or IT closet where you need monitored redundancy, AAA-integrated management, and Modbus TCP for a facilities dashboard — without stepping up to a full smart PDU with per-outlet switching that adds cost you don't need if manual outlet control isn't a requirement.