How do I choose the right UPS size?

Start from the actual critical load (not the total building load). Add a loading margin (typically 20-30%) for headroom, then pick a UPS series whose capacity range covers the result. The ATENCO selector applies an 80% loading factor by default and ranks matching ATENCO UPS series by capacity, phase, battery type and redundancy.

What information do I need to select a UPS?

Application, critical load in kW or kVA, input/output phase (1:1, 3:1 or 3:3), preferred battery type (VRLA or lithium / LiFePO4), redundancy plan (N+1, parallel, LBS / dual-bus) and any site or monitoring requirements (outdoor cabinet, galvanic isolation, SNMP, generator compatibility).

Should I choose a single-phase or three-phase UPS?

Single-phase (1:1) UPS is suitable for small to medium IT and office loads up to ~10 kVA. Three-phase input with single-phase output (3:1) suits sites with three-phase supply but single-phase critical loads. Three-phase (3:3) UPS is required when both supply and critical load are three-phase – typically data centers, large IT rooms and industrial infrastructure.

When should I choose a modular UPS?

Choose modular UPS when the project needs scalable capacity, N+X redundancy with hot-swappable modules, or future expansion without replacing the cabinet. ATENCO TM66E modular platforms cover 30 kVA up to 1.2 MW, with VRLA or lithium battery support by project configuration on selected sub-platforms.

Does ATENCO support lithium UPS batteries?

Yes, on selected platforms. RM11E PRO uses LiFePO4 lithium as standard for single-phase rack applications. TM33E 50-200 kVA, TM66E Modular 40-600 kVA and TM66E Large Modular 400 kVA to 1.2 MW support VRLA or lithium by project configuration. Other ATENCO series are VRLA only.

Can ATENCO calculate battery runtime?

Yes. Submit your selector configuration to ATENCO and an engineer will size the battery bank (number of strings, Ah rating, charger setting, runtime curve) against your actual load, target backup time, battery chemistry, site temperature and project conditions.

Can I send my selector result to ATENCO?

Yes. Use the Send Project Requirements button at the end of the guided builder. The selector pre-fills your application, load, phase, battery preference, redundancy and monitoring choices into the inquiry email so the ATENCO project team can review and reply with a sized UPS recommendation.

Selector -

Guided UPS Builder

Tell us about your project and we’ll rank the best-fit ATENCO UPS series, explain why, and flag what is not recommended. For sizing, enter the actual critical load – not the total building load.

1. What are you protecting?

2. Critical load

Enter the actual critical load. We apply an 80% loading margin to size the UPS.

3. Input / output phase Choose 3:3 when both supply and load are three-phase. Choose 3:1 when supply is three-phase but the protected load is single-phase. Pick “Not sure” to keep all options visible.

4. Battery preference Lithium / LiFePO4 is available on selected ATENCO platforms only (RM11E PRO and selected TM33E / TM66E platforms by project configuration).

5. Backup-time target Runtime depends on real load, UPS efficiency, battery chemistry, battery Ah, battery quantity, site temperature and battery age. ATENCO confirms final battery configuration by project.

6. Redundancy Parallel and LBS support varies by series and model – the recommended product page lists exact parallel-unit counts.

7. Site & special requirements (optional)

Modular scalability Generator compatibility Galvanic isolation Outdoor cabinet PF 1.0 output

Find the Right ATENCO UPS for Your Project

Guided UPS Builder

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Find the Right ATENCO UPS for Your Project

Guided UPS Builder

Product Comparison

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