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Product Model

Liebert EXL S1 250-400 kVA/kW

The Liebert EXL S1 is a monolithic, transformer-free UPS that features optimized, industry leading footprint and power per square foot, excellent operating efficiency, robust electrical protection and intelligent paralleling that optimizes performance at partial load to achieve superior cost savings. Available in single module and distributed bypass configurations. Compatible with lithium ion battery systems.

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Key Benefits
See the Digitial Infographic that overivews primary benefits
Space-saving design minimizes footprint
Maximizes active power capacity
Reduces operating expenses
Easy to service and install
Flexible configurations
Eliminates upstream electrical disturbances
Ensures robust power protection
Compatible with modern electrical loads
Intelligent and secure control is customizable by user
Flexible energy store options
EXL S1 safe capacity mode feature now available providing UPS load and battery discharge testing without an external load bank.
Best Suited For:
  • Banking, Financial and Insurance
  • Data Center/Colocation/Hosting
  • Healthcare
  • Government
Warranty: One Year Limited Warranty Against Defects in Material and Workmanship


Allows more space for revenue generating I.T. equipment by minimizing UPS footprint
Maximizes active power at unity power factor
Reduces operating expenses
Installation flexibility
Reduces total cost of ownership
Zero impact on upstream infrastructure
Compatible with modern mission critical loads
Delivers proactive remote services
EXL S1 safe capacity mode feature now available providing UPS load and battery discharge testing without an external load bank.


Smallest footprint among all competitors at this kVA size
Three modes of operating efficiency, Double Conversion (97%), Dynamic Online (99%) and ECO Mode (99%)
Advanced touchscreen control panel
Lithium ion battery compatible
Up to 8 units can be paralleled 
Intelligent paralleling option
High Impedance DC Ground Fault detection for 2014 NEC compliance
Dual asynchronous source / dual input capable

The Vertiv™ Liebert® EXL S1 UPS is available in 250-1200 kVA ratings and is optimized for maximum efficiency and power density. It offers the smallest footprint available for its kVA size range and is up to 60% smaller than some competitors. It is also significantly smaller than similar class UPS systems. For the conscientious buyer who needs every square foot to offer a positive ROI, such as for colocation providers, hosting and cloud businesses, the Liebert® EXL S1 UPS allows customers to either redeploy the saved space to implement more revenue generating IT equipment or reduce the actual design size of their equipment rooms, thus saving construction costs. Plus, the new Dynamic Online mode enables operating efficiency up to 99% without sacrificing availability. While in this mode, the inverter can instantaneously assume the load and maintain the output voltage within the IEC 62040 Class 1 specification, thus offering the same level of availability typically achieved in a double conversion operating mode. The new touchscreen control panel ensures Status At A Glance convenience, flexible views and multiple security options. Intelligent controls and communications integrate with Liebert® Nform, Liebert® SiteScan™ and the Liebert® Trellis™ Platform as well as 3rd party BMS and DCIM systems. LIFE™ Services provides 24x7 remote monitoring by our expert staff to improve availability and lower labor costs. The Liebert® EXL S1 UPS is fully compatible with the lithium ion battery solutions offered by Vertiv.

Liebert EXL S1 250-400 kVA/kW
Product Overview
Power Rating
250, 300, 400 kVA/kW
Input Voltage
480 volts
Output Voltage
480 volts
Up to 97% double conversion
Control Panel
Liebert standard touchscreen control panel
Cable Access
Top or bottom
Service Access
Front and top only
Operational Conditions
Operating Temperature
32 F - 104 F / 0 C - 40 C
FCC Part 15, Class A, IEC 62040-2, ANSI C624.41
UL 1778 5th Edition, CSA 22.2 NO 107.3
Transformer Free
Tools & Selectors
Select, compare, or configure UPS systems
UPS Selector
Interactive product selector for single-phase UPS
Liebert EXL S1 360 Interactive
Visualize and explore key features and benefits

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Products Support Contacts

Showing contacts for Virginia, 20149, USA Change
Vertiv (Liebert Services)
+1 800 543 2378
610 Executive Campus Drive Westerville Ohio 43082 USA
Product areas of focus: Uninterruptible Power Supplies (UPS), Power Distribution, Thermal Management, Integrated Solutions, Racks and Containment

Frequently Asked Questions

Is this UPS configurable?
Yes, the UPS is fully configurable at time of order.
Does this UPS work with lithium ion batteries?
Yes, it works with all manufacturers of lithium ion batteries sold by Vertiv.
Does this UPS come with a communications card?
Yes, we provide a standard LIFE Services card or you may choose an optional Unity dual simultaneous protocol card.
Does this UPS offer Eco-mode?
Yes, it offers Vertiv's unique Eco-mode which maintains battery charging and inverter readiness.
Can I change display and alarm values or does a service technician have to do it?
Yes, our standard touchscreen control panel is fully user configurable for type of information displayed, security access codes and warning & alarm parameters.
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