Vertiv / Liebert · EXL S1
The Vertiv Liebert EXL S1 is a large three-phase UPS, single-module or multi-module rated 250 to 1,200 kW at 480 V (60 Hz).

Vertiv lists the Liebert EXL S1 as current and names it as the replacement for the discontinued Liebert EXL (625 to 1,200 kVA) and Liebert NX 225 to 600 kVA.
Sources, checked October 3, 2026: Vertiv, Liebert EXL S1 UPS 250-1200 kW; Vertiv, Liebert EXL 625-1200 kVA (discontinued); Vertiv, high efficiency modes of operation (white paper).
2:06. Vertiv's own maintenance guide answers with a parts table: AC and DC filter capacitors, expected life 15 years, replaced at 12 to 15; low-profile fans, life more than 8 years, replaced at 6 to 7; air filters checked four times per year; and every battery chemistry with its own replacement window. DC capacitors idle over 18 months need formation. Design life is well in excess of 10 years, and well-maintained units run 20 or more. Source: Vertiv's EXL S1 Operation and Maintenance Guide SL-26090, section 5.2.3 and Table 5.1.
0:00 What does a maintenance visit check on a Liebert EXL S1? What does a maintenance visit check on a Vertiv Liebert EXL S1? Vertiv's own maintenance guide answers with a parts table, and the headline is good: the design life is well in excess of ten years, and well-maintained units can keep paying for twenty years or more.
0:16 What does the table say about capacitors? What does the table say about capacitors? The power AC and DC filter capacitors each have an expected life of fifteen years, with replacement proposed at twelve to fifteen. And if the modules sit out of service for more than eighteen months, those DC capacitors need formation before they go back to work.
0:35 What about the fans? What about the fans? The low-profile fans have an expected life of more than eight years, with replacement proposed at six to seven.
0:43 And the filters? And the filters? Air filters have a life of 1-3 years, and the guide has them checked four times per year.
0:49 Which batteries does it take? Which batteries does it take? The table covers all of them: the logic memory backup battery, a lithium cell with a ten-year life, replaced at eight to nine. Wet-cell batteries, fifteen to twenty years of life, replaced at twelve to fifteen. Sealed lead-acid batteries: a 5-year design is replaced at two to three years, a 10-year design at three to four, and a twenty-year design at eight to twelve. And lithium-ion: fifteen years of life, replaced at ten.
1:18 What is the caveat? What is the caveat? Vertiv's own: the expected life of each component is simply an estimate and is not a guarantee. The visit is where those estimates get checked against your site.
1:29 What is on you between visits? What is on you between visits? The read-only routine: the alarms and the log from the display, and the room conditions from the front. Everything else, including breakers, power cabinets and batteries, is technician work.
1:42 And a new EXL S1? And a new EXL S1? The startup is commissioned by Vertiv; this video is for units in service. If your EXL S1 is due for a visit, request a quote at threephaseups.ca.
How a three phase double conversion UPS carries the load, and where the bypass sits.
The orderable configurations we supply and service:
| Model | Rating | Phase / Voltage | Part number | Status |
|---|---|---|---|---|
| Liebert EXL S1 100kW | 100 kW | 3ph 3/4-wire in/out 400V (380/475 sel.) | EXL S1 100 kVA | Current |
| Liebert EXL S1 120kW | 120 kW | 3ph 3/4-wire in/out 400V (380/475 sel.) | EXL S1 120 kVA | Current |
| Liebert EXL S1 160kW | 160 kW | 3ph 3/4-wire in/out 400V (380/475 sel.) | EXL S1 160 kVA | Current |
| Liebert EXL S1 200kW | 200 kW | 3ph 3/4-wire in/out 400V (380/475 sel.) | EXL S1 200 kVA | Current |
| Liebert EXL S1 250kVA | 250 kW | 3ph 3/4-wire in/out 400/480V | EXL S1 250 kVA | Current |
| Liebert EXL S1 300kW | 300 kW | 3ph 3/4-wire in/out 400V (380/475 sel.) | EXL S1 300 kVA | Current |
| Liebert EXL S1 400kW | 400 kW | 3ph 3/4-wire in/out 400V (380/475 sel.) | EXL S1 400 kVA | Current |
| Liebert EXL S1 500kW | 500 kW | 3ph 3/4-wire in/out 400V (380/475 sel.) | EXL S1 500 kVA | Current |
| Liebert EXL S1 600kW | 600 kW | 3ph 3/4-wire in/out 400V (380/475 sel.) | EXL S1 600 kVA | Current |
| Liebert EXL S1 625kVA | 625 kW | 3ph 3/4-wire in/out 400/480V | EXL S1 625 kVA | Current |
| Liebert EXL S1 750kVA | 750 kW | 3ph 3/4-wire in/out 400/480V | EXL S1 750 kVA | Current |
| Liebert EXL S1 800kW | 800 kW | 3ph 3/4-wire in/out 400V (380/475 sel.) | EXL S1 800 kVA | Current |
| Liebert EXL S1 1000kW | 1000 kW | 3ph 3/4-wire in/out 400V (380/475 sel.) | EXL S1 1000 kVA | Current |
| Liebert EXL S1 1100kVA | 1100 kW | 3ph 3/4-wire in/out 400/480V | EXL S1 1100 kVA | Current |
| Liebert EXL S1 1200kW | 1200 kW | 3ph 3/4-wire in/out 400V (380/475 sel.) | EXL S1 1200 kVA | Current |
The Liebert EXL S1 introduced Vertiv’s Dynamic Online mode, which reaches up to 99% efficiency with a 0 ms transfer from high-efficiency to inverter mode, against up to ~10 ms on legacy designs, so the inverter can take the load instantly and hold output within IEC 62040-3 Class 1. That removes the usual trade-off where classic ECO mode buys efficiency at the cost of protection. Vertiv frames three IEC operating modes, full double conversion (VFI), active filtering / high efficiency (VI) and maximum energy saving (VFD).
Source: Vertiv, High efficiency modes of operation (white paper). Figures are Vertiv’s published specifications.
Battery strings and cabinets depend on the configuration and runtime. Battery kits that suit this platform are in the Vertiv / Liebert UPS battery catalogue.
We service the Vertiv Liebert EXL S1 across Canada: preventive maintenance, battery replacement and emergency repair, including units the manufacturer no longer supports. We are a Canadian UPS service and supply provider, working on three-phase systems since 2012.
Planned visits and emergency calls are arranged through on-site service for the Vertiv Liebert EXL S1.
We engineer the solution: load and growth analysis, redundancy (N, N+1, 2N), runtime and battery sizing, paralleling and switchgear, and custom configurations where the standard catalogue doesn't fit. Because we supply every major brand, the EXL S1 is one option we weigh on its merits, not the only answer.
The Vertiv Liebert EXL S1 is a large three-phase UPS, single-module or multi-module rated 250 to 1,200 kW at 480 V (60 Hz).
No. Vertiv lists the Liebert EXL S1 as current and names it as the replacement for the discontinued Liebert EXL (625 to 1,200 kVA) and Liebert NX 225 to 600 kVA.
A Canadian UPS service and supply provider, in business since 2012, services the Vertiv Liebert EXL S1 across Canada: preventive maintenance, battery replacement and emergency repair, including discontinued units. Call 1 (438) 881-3363 or email info@threephaseups.ca.
Tell us the application and we reply within 4 business hours with the sizing, the right system, the installation and a written quote. Three-phase installs usually need a licensed electrician, so let us know if you have one.
Brand names are trademarks of their owners and are used only to identify the equipment we service. We are not the manufacturer and are not affiliated with it.