P91g Online UPS – 1500–3000 VA, 208–240V Rack UPS with Scalable Runtime

The P91g Series is a double-conversion online UPS designed for applications where uptime, voltage stability, and runtime flexibility are required without moving to larger centralized systems.

It is commonly deployed in distributed IT, AV, retail, and commercial infrastructure where external battery expansion is needed to support site-specific runtime requirements.

Key Specifications

• 1500 / 2000 / 3000 VA
• 208–240 VAC single phase
• Online double-conversion topology
• Unity output power factor (1.0)
• Internal VRLA batteries with external expansion
• 2U rack / tower convertible form factor
• Wall-mount support (1500 / 2000 VA models)
• Programmable charger (1–12A)
• Optional SNMP / network monitoring
• CE, RoHS, TAA compliant

Datasheet:
https://xpcc.com/wp-content/uploads/P91g-1-3kVA-Flyer.pdf

Scalable Runtime and Continuous Power Protection

The P91g is designed around a runtime-flexible architecture. Unlike compact UPS systems with fixed internal batteries, it supports external battery cabinets to align runtime with application requirements.

Online double-conversion topology ensures that connected equipment is continuously powered by conditioned output, independent of upstream disturbances. During outages, the system maintains zero transfer time while sustaining load through battery energy.

This architecture supports both short-duration ride-through and extended runtime strategies across distributed deployments.

Where P91g Fits in Rack Power Architecture

P91g operates as the standard 208–240V online UPS platform within a distributed power architecture, providing a balance between power conditioning and runtime scalability.

It is typically deployed:

• at the rack or closet level for localized protection
• in multi-site environments requiring standardized UPS platforms
• alongside downstream PDUs for distribution and control

For broader system design context:
https://xpcc.com/rack-power-architecture/

P91g vs Conventional Compact Online UPS

Compared to typical compact 2U UPS platforms, P91g is designed to support higher real load capacity and more flexible runtime configurations.

The platform delivers full usable output without derating, while its programmable charging system supports larger external battery strings than many competing systems. This enables faster recharge and improved recovery after extended outages.

The result is a UPS that can be deployed consistently across sites with varying runtime requirements, rather than being constrained by fixed internal battery designs.

Replace APC / Eaton 230V Online UPS Systems

P91g is commonly deployed as a replacement for legacy compact online UPS platforms including:

• APC Smart-UPS Online (SRT series)
• Eaton 9130 and early 9PX models
• Vertiv Liebert GXT systems

It provides a modernization path with improved real-power utilization, higher charging capacity, and scalable runtime architecture.

Detailed comparisons:
https://xpcc.com/p91g-ups-competitive-comparisons/

Runtime Architecture and Deployment Flexibility

The ability to scale runtime externally allows P91g to support a wide range of deployment strategies.

It can be configured for:

• short ride-through to generator start
• controlled shutdown of IT systems
• extended runtime for critical edge infrastructure

This flexibility makes it suitable for environments where runtime requirements vary significantly between locations.

P91g vs Lithium UPS Platforms

P91g represents a VRLA-based approach optimized for runtime scalability and lower upfront cost.

Within the Xtreme Power portfolio:

• P91g → scalable runtime using external VRLA batteries
• P91 Li → lithium platform with reduced maintenance and longer lifecycle
• J90i → high-density 1U lithium UPS with integrated control

P91g is typically selected when external battery expansion and cost structure are prioritized over lifecycle optimization.

For lithium comparison:
https://xpcc.com/lithium-ups-guide/

Typical Applications

P91g is deployed across a wide range of distributed infrastructure environments, including AV systems, retail and hospitality, education facilities, and network closets.

It is particularly well suited for applications requiring consistent UPS platforms across multiple sites with different runtime requirements.

Capacity Guidance

Capacity selection is based on load profile and runtime objectives:

• 1500 VA → small AV and edge systems
• 2000 VA → network infrastructure and distributed IT
• 3000 VA → higher-density switching and edge compute

Runtime should be defined based on outage duration and shutdown strategy.

UPS sizing tool:
https://xpcc.com/selector

Xtreme Power UPS Platform Context

P91g fits within the broader UPS architecture as the global online runtime platform:

• A60 → standby UPS (device-level protection)
• S71 → line-interactive UPS
• P80 / P80g → line-interactive rack UPS
• P91 / P91g → online UPS with scalable runtime
• P91 Li → lithium runtime platform
• J90 / J90i → high-density lithium UPS

Technical Summary

Topology: Online double conversion
Capacity: 1500–3000 VA
Voltage: 208–240 VAC
Battery: VRLA (internal + external expansion)
Form Factor: 2U rack / tower / wall-mount
Runtime: Scalable
Monitoring: Optional SNMP / web
Compliance: CE, RoHS, TAA

Plan With Confidence

Xtreme Power Conversion supports engineers, integrators, and infrastructure planners in designing UPS systems with scalable runtime and global deployment flexibility.

Phone: (800) 582-4524
Email: sales@xpcc.com