How do the power capacity, efficiency, and output quality compare between the two units?

Both UPS units are rated at 6000 VA / 6000 W, reflecting a unity (1.0) power factor — a meaningful advantage over older 0.8 pf designs when powering modern switched-mode power supplies. APC specifies efficiency at 94.4% in online double-conversion mode, output voltage THD at ≤3%, and a crest factor of 3:1, all of which are documented in the SRT6KXLI spec sheet. The GXT5LI-6000GVRT3UXLN's efficiency figure and output THD are not provided in the supplied specifications; buyers requiring a verified efficiency number for energy-cost modeling or green-building certification must consult Vertiv's full datasheet.

The SRT6KXLI accepts a wide input voltage range of 100–275 V at 40–70 Hz, making it tolerant of highly variable utility power. The GXT5LI-6000GVRT3UXLN's input is specified at 200–240 V, which is narrower and consistent with a unit designed strictly for 200–240 V single-phase environments. APC also documents surge energy absorption at 480 J with surge protection confirmed; neither figure is supplied for the Vertiv unit.

Output voltage regulation for the Vertiv is ±1% with a user-configurable range of 200–240 VAC (default 230 VAC), a precise figure that is not provided for the APC in the supplied specs beyond the 220–240 V range notation. Audible noise for the SRT6KXLI is listed at 55 dB; no noise specification is given for the GXT5LI-6000GVRT3UXLN.

What are the installation requirements and physical footprint differences?

The Vertiv GXT5LI-6000GVRT3UXLN has fully documented physical dimensions: 5.25 in H × 16.9 in W × 35 in D, weighing 99 lbs, in a 3U rack form factor (implied by the 'RT3U' model suffix). Its input wiring is hardwired (L1-L2/N-G), which requires a licensed electrician for installation and a dedicated circuit breaker, but eliminates plug compatibility concerns in high-current deployments. Physical dimensions and weight are not provided in the supplied specifications for the SRT6KXLI; buyers cannot make a direct rack-space or floor-loading comparison from the data provided here.

The SRT6KXLI supports Emergency Power Off (EPO), a code-required feature in many data center and colocation environments. EPO status is not confirmed in the supplied Vertiv specifications. The SRT6KXLI's output frequency is regulated at 50/60 Hz; the Vertiv's output frequency regulation is not specified in the provided data.

Operating temperature for the Vertiv is 32°F–104°F (0°C–40°C) with a 10% derating at 50°C (122°F), which is important for edge or industrial locations that may exceed standard ASHRAE A1 conditions. The SRT6KXLI's operating temperature range is not included in the supplied specifications.

Which unit offers stronger compliance certifications and what battery technology is used?

Battery chemistry is a decisive differentiator. The Vertiv GXT5LI-6000GVRT3UXLN is explicitly a lithium-ion UPS (denoted by 'LI' in the model name), certified to IEC 62619 (the international safety standard for secondary lithium cells in stationary applications). Lithium-ion batteries typically offer longer calendar life (8–10+ years vs. 3–5 years for VRLA), lower weight per kWh, and a wider operating temperature range than traditional VRLA — though none of these comparative figures are provided directly in the supplied specs and should be verified with Vertiv's full documentation. The SRT6KXLI's battery chemistry is not stated in the provided specifications.

The Vertiv carries a comprehensive list of agency approvals: IEC 62040-1:2008+A1 2013, IEC 62040-2 2nd Ed., IEC 61000-3-2, IEC 61000-3-12, CISPR 22 Class A, FCC Part 15 Class A, and UL 1778. UL 1778 is the North American UPS safety standard required by many insurance and facilities teams. No agency certifications are listed in the supplied APC specifications; APC Smart-UPS products typically carry similar listings but buyers must verify independently.

The SRT6KXLI's 'SRT' designation is associated with APC's Smart-UPS On-Line family, which supports an optional network management card (NMC) for SNMP/web monitoring — but no management or communications spec is included in the supplied data for either unit. Neither unit's runtime curves, battery capacity (Ah/kWh), or recharge time are provided in the supplied specifications for direct comparison.

Which should you choose: the SRT6KXLI or the GXT5LI-6000GVRT3UXLN?

Our take: The GXT5LI-6000GVRT3UXLN is the stronger choice when lithium-ion battery longevity, a fully documented physical footprint, and a complete agency-certification record are the top priorities. It provides a verified 3U rack form factor (5.25 in H × 16.9 in W × 35 in D, 99 lbs), IEC 62619 lithium-ion safety certification, UL 1778 listing, and ±1% output voltage regulation — all confirmed in the supplied specs. The SRT6KXLI holds the advantage on documented efficiency (94.4%), input voltage range (100–275 V vs. 200–240 V), confirmed EPO support, surge energy rating (480 J), and audible noise (55 dB) — specs absent from the Vertiv data provided. The SRT6KXLI suits deployments with variable or wide-swing utility power and strict EPO code requirements. The GXT5LI-6000GVRT3UXLN suits facilities standardizing on lithium-ion for reduced maintenance and hardwired 200–240 V single-phase circuits. Several key specs are missing for each model; a complete comparison requires both full datasheets.

Side-by-Side Comparison

Spec-for-spec, from manufacturer data.

Frequently Asked Questions

Related Resources

• APC by Schneider Electric SRT6KXLI product page — full specs and to add to a quote
• Vertiv GXT5LI-6000GVRT3UXLN product page — full specs and to add to a quote