Vertiv Rpdu Rack Transfer Switch Monitored Outlet Level 20A 120V 1.9KW Horizontal - VA6N21A0

Vertiv VA6N21A0 Monitored Outlet-Level Rack Transfer Switch

Overview

The Vertiv VA6N21A0 is a horizontal 0U rack-mount, single-phase rack transfer switch (RTS) with monitored outlet-level power distribution — the right specification when you need per-outlet current, voltage, and power visibility combined with automatic source switching in a 20A, 120V environment. Designed for data center cabinets and equipment rooms where two power feeds are available, the VA6N21A0 automatically transfers connected loads to the secondary input if the primary source degrades or fails, without interrupting equipment that tolerates a sub-cycle switchover. The unit draws from a NEMA 5-20P plug on a 3-meter (roughly 10-foot) cord — long enough to reach overhead whips or floor-mounted PDU taps in most standard 42U cabinets without an extension.

Key Features

• Outlet-Level Power Monitoring: All six NEMA 5-20R receptacles report current, voltage, and power individually via the LCD display and network interface. In a mixed-density cabinet, knowing which outlet is drawing 11A versus 4A lets you rebalance loads before a breaker trips — something a simple metered PDU can't give you at the receptacle level.
• Automatic Transfer Switching: The unit monitors both input sources continuously and switches the load to the secondary feed on source anomaly or loss. For servers, network switches, and storage arrays with single-corded power supplies — or any device where the PSU itself isn't the redundancy — this delivers the fault tolerance you'd otherwise only get with dual-corded hardware.
• 20A / 120V Single-Phase Rating at 1.9 kW: At 20A input (NEMA 5-20P), the VA6N21A0 supports up to 1.9 kW of connected load across six outlets. Budget load headroom at 80% of breaker capacity (16A / 1.52 kW sustained) per NEC practice — enough for a mix of 1U servers, KVM switches, and ancillary gear in a secondary or edge cabinet.
• Six NEMA 5-20R Receptacles: Six outlets in a single horizontal unit keeps your cabinet cabling organized with a single power bar rather than stacking multiple strips. All receptacles are 5-20R, accepting the common 5-15P and 5-20P plugs found on most rack-mount IT and security gear at this voltage.
• LCD Display with LED Indicators: The front-panel LCD shows real-time load data without requiring a network connection — useful during commissioning, troubleshooting, or when you're physically in front of the cabinet and need a quick sanity check. LED indicators provide at-a-glance status on source health and load state.
• 3-Meter Input Cord: The factory-attached 3m (approximately 10 ft) power cord gives enough reach in most data center cabinet layouts to connect to floor-level or overhead source PDUs without cable management headaches. A hardwired cord also eliminates the loosened-plug failure mode common on field-assembled connections.
• Horizontal 0U Form Factor: Mounting horizontally in a standard rack, the VA6N21A0 fits into the PDU channel on cabinet side panels or can occupy a 1U slot with appropriate mounting hardware — keeping the full usable rack unit depth available for active equipment rather than sacrificing rack space to a vertical strip.

Network Management and Protocol Support

The onboard Ethernet (RJ-45) interface and serial port give you two independent management paths. Network protocol support spans SNMP v1/v2c/v3, HTTPS, SSH, SMTP alerting, Syslog, NTP time sync, DHCP/static IP on both IPv4 and IPv6, plus enterprise authentication via LDAP, RADIUS, and TACACS+. Modbus TCP is also supported for building management system (BMS) or DCIM integrations where the PDU needs to surface power data into a broader facility platform. SNMP v3 specifically means encrypted, authenticated traps — a requirement in many federal, healthcare, and financial environments where v1/v2c community strings are not acceptable. The USB port provides an additional local management or firmware update path without needing a serial adapter.

For Vertiv power distribution deployments already standardized on Vertiv's management ecosystem, the VA6N21A0 integrates with that platform's dashboards natively. If you're building out a managed rack PDU infrastructure across multiple cabinets, consistent SNMP v3 coverage across all outlets simplifies your monitoring stack.

Integration and Compatibility

The breadth of supported protocols — LDAP, RADIUS, TACACS+ for AAA; SNMP v3 for monitoring; Modbus TCP for BMS/DCIM — makes the VA6N21A0 compatible with enterprise network management platforms, DCIM tools, and security policy frameworks without requiring vendor-specific software. Syslog output feeds directly into SIEM or log aggregation systems. If you're specifying monitored PDUs for a cabinet refresh and your security policy requires encrypted management channels, HTTPS and SSH cover both browser-based and CLI access. Pair with a UPS on each input feed to extend the transfer switch's redundancy concept all the way back to battery backup — the RTS handles source switchover in microseconds, but true ride-through during a complete outage still requires upstream UPS capacity.

Frequently Asked Questions

Q: What is the maximum load the VA6N21A0 can support?

A: The VA6N21A0 is rated at 20A input and 1.9 kW. Following standard NEC practice, plan for a sustained load no greater than 80% of breaker rating — approximately 16A or 1.52 kW — across all six outlets combined.

Q: Does the VA6N21A0 support IPv6?

A: Yes. Both IPv4 and IPv6 are supported on the Ethernet management interface, along with DHCP on either protocol version for flexible network integration.

Q: What authentication protocols does the VA6N21A0 support for network access?

A: LDAP, RADIUS, and TACACS+ are all supported for centralized authentication and authorization, in addition to local account management. This covers most enterprise AAA environments.

Q: Is SNMP v3 supported on the VA6N21A0?

A: Yes. SNMP v1, v2c, and v3 are all supported. SNMP v3 provides encrypted, authenticated traps and polling — the required version for environments with strict network security policies where v1/v2c community-string authentication is not acceptable.

Q: Can the VA6N21A0 integrate with building management or DCIM systems?

A: Yes. Modbus TCP support allows the VA6N21A0 to surface power data (current, voltage, power) to BMS and DCIM platforms that use Modbus as a southbound protocol, in addition to SNMP-based NMS/DCIM integrations.

Q: What plug type does the VA6N21A0 use, and how long is the cord?

A: The input plug is NEMA 5-20P on a factory-attached 3-meter (approximately 10-foot) cord. The six output receptacles are NEMA 5-20R, which also accept standard NEMA 5-15P plugs.

Ted Perry

The VA6N21A0 is one of the more practical tools in a data center power redundancy toolkit — it gives you automatic source transfer and outlet-level monitoring (current, voltage, and power on all six receptacles) in a horizontal 0U form factor without requiring a dual-corded device on every connected load. I reach for this unit specifically when I'm building out a cabinet with single-PSU edge servers or single-corded appliances that can't self-protect through PSU redundancy.

Technical Highlights:

• SNMP v3 + TACACS+ + LDAP: The full AAA and encrypted monitoring stack on a single-phase 20A unit is meaningful — most environments that enforce SNMP v3 and centralized auth need it down to every managed outlet, not just at the row-level PDU. The VA6N21A0 checks every box without an external management gateway.
• Modbus TCP: This is the spec that separates it from IT-only PDUs. Modbus TCP means your DCIM or BMS can poll this unit directly alongside UPS, CRAC, and other facility gear — you get unified power telemetry without a protocol translator in the middle.
• Outlet-Level Monitoring on All 6 Receptacles: At 1.9 kW across six 5-20R outlets, per-outlet visibility tells you which device is actually drawing what — critical when you're load-balancing a cabinet refresh or diagnosing a branch circuit that keeps hitting its 80% threshold.

Deployment Considerations:

• This is a 120V / 20A unit — confirm both input feeds are 20A circuits before installation. Mixing a 15A circuit as the secondary source creates a mismatch that will trip the secondary breaker under moderate load during a transfer event.
• The 3m input cord reaches most overhead whip configurations in 42U cabinets, but measure your secondary feed tap location before ordering — if your secondary source PDU is floor-mounted at the rear and your RTS is mid-cabinet, 3m may be marginal.

Best fit: a colocation cage or enterprise equipment room where the operator is adding a secondary power feed to cabinets that originally had single-feed designs, and where the managed network team requires SNMP v3 and centralized auth down to the outlet level — not just at the row PDU.