PER1103+Li 2U lithium UPS 3000VA 48v online double conversion

Q: How long can a 3000VA 48V lithium ion UPS provide backup power?

Backup time cannot be determined from the UPS power rating and battery voltage alone. It depends on battery capacity in watt-hours, usable battery energy, load power, conversion losses, discharge-current limits, and battery management settings. The battery configuration should be selected according to the required runtime.

Prostar PER1103+Li 2U lithium UPS 3000VA 48v online double conversion, designed to provide continuous, conditioned power for servers, networking equipment, telecommunications systems, and other critical electronic loads. Featuring online double-conversion technology, a 48V lithium battery system, and a compact 2U chassis, this UPS combines power protection with flexible installation options.

Its standout design feature is a 90-degree rotatable LCD display, allowing the same unit to be installed as either a rack mount UPS or a tower UPS. This dual-orientation design helps businesses adapt to different equipment layouts without selecting separate UPS models for different installation environments.

Table of Contents

Modern IT Infrastructure Needs More Than Basic Backup Power

Servers, network switches, storage devices, telecommunications equipment, and industrial control systems depend on a stable electrical supply. Even brief interruptions, voltage fluctuations, or power-quality disturbances can disrupt operations, interrupt communications, or cause unexpected equipment shutdowns.

Traditional standby UPS systems may not provide the continuous power conditioning required by sensitive electronic loads. Meanwhile, conventional rack-only UPS installations can be inconvenient for businesses operating mixed equipment rooms, small server cabinets, branch offices, and facilities with limited floor space.

Battery selection presents another challenge. Businesses increasingly consider lithium batteries for backup power because lithium-based systems can offer different maintenance, monitoring, and service-life characteristics compared with conventional lead-acid batteries. However, a lithium UPS must also provide appropriate battery management compatibility and electrical protection.

These challenges create several practical requirements:

Continuous power conditioning for sensitive electronic equipment.
Sufficient active power capacity for the intended load.
Compact installation in a standard equipment rack or on a suitable tower stand.
Reliable communication between the UPS and monitoring systems.
Battery protection and configurable charging parameters.
Efficient operation without unnecessary energy losses.

The Prostar PER1103+Li 2U lithium UPS addresses these requirements through an integrated online UPS platform with flexible installation, lithium battery compatibility, and multiple communication options.

2U Lithium UPS with Online Double-Conversion Technology

Online Double-Conversion Technology for Continuous Power Conditioning

The PER1103+Li uses online double-conversion technology. In normal operation, incoming AC power is converted to DC and then inverted back to AC, helping isolate the connected equipment from variations in the incoming electrical supply.

Unlike standby UPS designs that normally supply utility power directly to the load, an online double-conversion UPS continuously supplies power through its conversion stages during normal online operation.

This architecture is suitable for applications where power continuity and output quality are important, including servers, network infrastructure, telecommunications systems, and selected industrial electronics.

The PER1103+Li specifies 0ms transfer time from AC mode to battery mode and from battery mode to AC mode. This means the specified operating-mode transitions do not require a break in output power. Transfer between inverter and bypass is specified at 4ms, so bypass operation should be evaluated separately when assessing power continuity requirements.

Its pure sine wave output, battery-mode voltage regulation of ±1%, and battery-mode frequency accuracy of ±0.1% support sensitive loads requiring controlled AC power.

PER1103+Li 2U lithium UPS 3000VA 48v online double conversion diagram

A Compact 2U Lithium UPS for Space-Constrained Installations

The PER1103+Li has a chassis measuring 440 × 420 × 88 mm, occupying 2U of vertical rack space in rack-mounted installations.

A compact 2U lithium UPS can help IT integrators preserve rack space for servers, switches, storage systems, and other equipment. Its form factor is particularly relevant to installations where the available rack height is limited.

The unit light weight, making it relatively straightforward to position compared with larger UPS cabinets, subject to the installation and rack-support requirements.

For projects without a dedicated server rack, the PER1103+Li can also be configured for tower installation. The 90-degree rotatable LCD allows the screen orientation to match the selected installation position, improving display readability without requiring a different UPS model.

Lithium Battery Compatibility with Integrated Protection

The PER1103+Li supports LiFePO4 lithium batteries as well as lead-acid batteries. Its nominal battery-system voltage is specified as 48VDC, with 51.2VDC nominal for the LiFePO4 configuration.

The UPS provides configurable charging current from 1A to 30A, with a default setting of 5A. It also specifies smart battery management, automatic restart, and self-test functions.

For compatible lithium battery configurations, the documented battery management protection functions include:

Overcharge protection.
Over-discharge protection.
Overcurrent protection.
Short-circuit protection.
Overtemperature and undertemperature protection.

Native support for Pylontech RS485 and CANbus protocols is also specified. Battery compatibility must nevertheless be confirmed for the selected battery model, firmware, communication interface, and BMS configuration before deployment.

Key Features & Benefits

Key feature	Technical specification	Customer benefit
Online double conversion	Online UPS architecture	Continuous power conditioning for sensitive electronic loads
Rated capacity	3000VA / 3000W	Supports loads within the UPS’s rated capacity
Compact 2U chassis	440 × 420 × 88 mm	Conserves vertical space in equipment racks
Rack/tower convertible design	90° rotatable LCD	Supports different equipment-room layouts
Lithium battery compatibility	48V system; 51.2V nominal LiFePO4	Supports lithium-based backup configurations
Pure sine wave output	Pure sine wave	Suitable for compatible electronic equipment requiring sinusoidal AC
High AC-mode efficiency	Greater than 94%	Helps reduce UPS conversion losses under specified operating conditions
Communication interfaces	USB and RS485 for BMS	Supports local monitoring and battery communication
Optional expansion slot	SNMP or dry-contact cards	Enables additional monitoring and integration options
Selectable output voltage	208/220/230/240VAC	Accommodates supported regional voltage requirements

Why the Rotatable LCD and Dual-Installation Design Matter

A major advantage of the PER1103+Li is its ability to operate in either rack-mounted or tower installation arrangements.

Many businesses use different installation formats across their facilities. A centralized IT room may have a 19-inch equipment rack, while a branch office, retail site, or small control room may use a floor-standing equipment arrangement.

A conventional rack-oriented design may be inconvenient when the installation changes. A tower-only model, conversely, may consume rack space unnecessarily when integrated into a server cabinet.

The PER1103+Li offers an alternative: one 2U lithium UPS platform that can be configured for either arrangement, with a 90-degree rotatable LCD to maintain a suitable display orientation.

Installation factor	Rack-mounted configuration	Tower configuration
Typical environment	Server racks, network cabinets, IT rooms	Offices, equipment rooms, compact control spaces
Space utilization	Uses 2U of rack height	Uses suitable floor or shelf space
LCD orientation	Adjusted for rack installation	Rotated 90° for vertical installation
Equipment layout	Integrated with rack-based equipment	Suitable for non-rack equipment layouts
Procurement implication	One UPS model can serve rack-based projects	The same model can serve compatible tower-based projects

Installation note: Rack rails, rack ears, tower stands, and other mounting accessories should be confirmed with Prostar for the specific package. The chassis dimensions alone do not establish compatibility with every rack or mounting kit.

Technical Specifications

General and Input Specifications

Parameter	Specification
Model	PER1103+Li
Rated capacity	3000VA / 3000W
Form factor	2U rack mount / tower convertible
Dimensions (W × D × H)	440 × 420 × 88 mm
Net weight	8.2 kg
Input phase	Single-phase, L+N+PE
Input power factor	≥0.99 at nominal input voltage
Total harmonic distortion (THDi)	Less than 6%
Frequency range	44–56Hz at 50Hz; 54–66Hz at 60Hz
High line transfer	300VAC ±5%
High line recovery	290VAC ±5%
Low line transfer	Load-dependent; 110–176VAC according to specified load conditions

Output and Performance Specifications

Parameter	Specification
Selectable output voltage	208/220/230/240VAC
Output waveform	Pure sine wave
Battery-mode voltage regulation	± 1%
Battery-mode frequency accuracy	50Hz or 60Hz ±0.1%
Crest factor	3:1
Total harmonic distortion(THDv)	<3% THD (Linear Load), <6% THD (Non-linear Load)
AC-to-battery transfer time	0ms
Battery-to-AC transfer time	0ms
Inverter-to-bypass transfer time	4ms
AC-mode efficiency	Greater than 94%
Battery-mode efficiency	Greater than 90%
Noise level	Less than 50dBA at 1m

Battery, Communication and Environmental Specifications

Parameter	Specification
Supported battery types	LiFePO4 lithium / lead-acid
Nominal battery voltage	48VDC; 51.2VDC nominal for LiFePO4
Charging current	5A default; configurable from 1A to 30A
Charging voltage	56.4VDC, as specified
Charging algorithm	2-stage CC/floating or 3-stage CC/CV/floating
Battery management	Smart battery management and specified BMS protection functions
BMS communication	RS485
Supported lithium battery protocols	Native Pylontech RS485 and CANbus protocol support
Standard communication interfaces	USB/RS232, RS485 for BMS
Optional expansion cards	SNMP / dry-contact cards
Operating temperature	0°C to 40°C
Operating humidity	20%–95%, non-condensing
Storage temperature	−15°C to 60°C, excluding battery
Operating altitude	1,000m; derating applies at higher altitudes up to 4,000m

Practical Applications

A 3000VA 48V lithium ion UPS is not defined by capacity alone. Its suitability depends on the connected equipment, peak demand, power quality requirements, battery configuration, and expected backup duration.

The PER1103+Li combines a 3kW active power rating with online double conversion, selectable output voltage, and rack/tower installation flexibility. These characteristics make it relevant to several application categories.

Application Scenarios

Server Rooms and IT Infrastructure

Supports compatible servers, network switches, storage devices, and related IT equipment. Online power conditioning is relevant where power interruptions or input fluctuations could affect service availability.

Telecommunications and Networking

Provides conditioned backup power for compatible communication equipment. USB, RS232, RS485, and optional SNMP or dry-contact expansion support different monitoring and integration requirements.

Industrial Control Systems

Can protect suitable control electronics, automation computers, and monitoring devices, provided the equipment’s load profile and environmental requirements are within specification.

Branch Offices and Small Equipment Rooms

The rack mount and tower convertible design helps integrators standardize on one UPS model across different installation layouts.

How to Size the UPS for a Real Application

The PER1103+Li 2U lithium UPS is rated at 3000VA/3000W. This does not mean every combination of equipment totaling 3kW will be suitable under all conditions.

Before specifying the UPS, an installer should:

Calculate the connected equipment’s continuous active power demand in watts.
Account for startup currents, transient loads, and the crest-factor requirements of connected equipment.
Maintain sufficient capacity margin for load changes and future expansion.
Confirm that the equipment accepts the selected output voltage and frequency.
Calculate the required backup time and verify battery capacity, discharge current, and BMS limits.
Confirm communication compatibility if remote battery monitoring or automated shutdown is required.

For example, a nominal 2,000W load represents approximately 66.7% of the UPS’s 3,000W rated active power capacity. This is a capacity calculation, not a runtime estimate. Actual backup time depends on the connected battery capacity, discharge characteristics, UPS losses, and operating conditions.

90° Rotatable LCD

The rotatable display improves installation flexibility and user experience.

When a UPS rotates from rack orientation to tower orientation, a fixed display may appear sideways.

The PER1103+Li solves this with a 90‑degree rotatable LCD interface.

The display remains visually aligned with the physical orientation of the UPS.

This provides several practical benefits:

Easier status checking
Better readability
Cleaner installation appearance
More flexible deployment
Easier commissioning
Improved service accessibility

For system integrators, this also reduces the need to stock separate rack and tower versions for certain applications.

2U lithium rack mount UPS 90° Rotatable LCD

Lithium UPS Detail

PER+Li Single Phase 2U Rack Mount Lithium UPS Rear

1. External Battery Connector	2. Emergency Power Off(Option)	3. RS485 Port for BMS
4. USB Port	5. AC Output Sockets	6. Grounding
7. Intelligent Slot(for SNMP Card or AS400 Dry Contact)	8. Input Circuit Breaker	9. AC Input Terminal

Lithium Battery Management, Charging and System Compatibility

LiFePO4 Lithium battery integration involves more than connecting a battery with the correct nominal voltage. A properly engineered system must consider charging parameters, discharge-current requirements, communication protocols, battery protection, and operating temperature.

The PER1103+Li specifies a 48V nominal battery system and 51.2V nominal voltage for LiFePO4 batteries. It also supports configurable charging current between 1A and 30A.

The specified charging voltage is 56.4VDC. The actual charging settings must be checked against the selected battery manufacturer’s requirements before commissioning.

The built-in battery management features include protection against overcharge, over-discharge, overcurrent, short circuit, and temperature excursions. Native support for Pylontech RS485 and CANbus protocols can simplify integration with compatible batteries, but protocol support alone does not guarantee compatibility with every battery model.

Battery Selection Checklist

Selection factor	What the installer should verify
Nominal voltage	Compatibility with the 48V UPS battery system
Battery chemistry	Approved LiFePO4 or lead-acid configuration
Charging voltage	Compatibility with the battery manufacturer’s specified charging profile
Continuous discharge current	Sufficient current capability for the actual load and DC bus voltage
BMS communication	Correct protocol, wiring, pinout, and configuration
Battery capacity	Sufficient usable energy for the required runtime
Temperature limits	Compliance with UPS and battery operating specifications
Protection coordination	Compatibility between UPS protections and battery BMS limits

For lithium battery projects, confirm the approved battery models and operating parameters with Prostar before finalizing the system design.

Communication and Remote Monitoring Options

Power protection is only one part of UPS system management. In multi-site IT environments, integrators may also need to monitor operating status, identify battery issues, and coordinate the UPS with network management or building control systems.

The PER1103+Li includes USB and RS485 for BMS communication. Its expansion slot supports optional SNMP or dry-contact cards.

Interface or option	Typical purpose	Implementation consideration
USB, RS232	Local UPS connection to a compatible computer	Confirm supported monitoring software and operating-system compatibility
RS485 for BMS	Communication with a compatible lithium battery management system	Confirm protocol, wiring and battery compatibility
Optional SNMP card	Network-based UPS monitoring	Confirm card model, software features and supported protocols
Optional dry-contact card	Status signaling to external systems	Confirm available signals and interface requirements

For distributors and system integrators, these options allow the UPS configuration to be matched to different customer monitoring requirements. Optional cards should be specified separately where they are not included in the standard configuration.

Frequently Asked Questions (FAQ)

What makes a 2U lithium UPS better than a traditional lead-acid rackmount UPS?

A 2U lithium UPS offers up to 3x longer operational lifespan (8-10 years), weighs significantly less, recharges much faster, and performs exceptionally well under elevated operating temperatures. This dramatically reduces maintenance visits, replacement costs, and cooling energy demands, leading to a much lower Total Cost of Ownership (TCO).

How does the rotatable LCD display on the PER1103+Li work?

The front LCD panel can be physically rotated 90 degrees. If you deploy the unit vertically as a standalone tower, you can rotate the display so the operating parameters (such as input voltage, load capacity, and battery status) remain perfectly horizontal and easy to read.

Does this 2U rack mount online UPS support LiFePO4 batteries?

Yes. The specification lists LiFePO4 lithium and lead-acid battery compatibility. The nominal battery-system voltage is 48VDC, with 51.2VDC nominal for the LiFePO4 configuration. Battery model, charging settings, discharge-current capability, and BMS communication must be verified before installation.

In a true online double-conversion UPS 3kVA like the PER1103+Li, power continuously flows through the AC-to-DC rectifier and DC-to-AC inverter. When a utility blackout occurs, the battery seamlessly supplies power to the inverter without any interruption (0ms transfer time). This prevents server resets, sensitive hardware crashes, and data loss.

How long can a 3000VA 48V lithium ion UPS provide backup power?