APC Smart-ups Ultra On-line Lithium ION 10KVA/10KW 4U Rack/tower 208/240V - SRTL10KRM4UT

APC by Schneider Electric SRTL10KRM4UT Smart-UPS Ultra On-Line 10KVA Lithium-Ion Rack UPS

Overview

The SRTL10KRM4UT is APC's 10KVA/10KW Smart-UPS Ultra, a double-conversion online lithium-ion UPS in a 4U rack/tower form factor built for 208/240V single-phase critical loads. Double-conversion topology means your equipment never rides directly on utility power — every watt passes through the inverter continuously, eliminating the transfer-time risk that's present in line-interactive designs. For power protection and UPS solutions, this positions the SRTL10KRM4UT squarely in the mission-critical tier, not the "just in case" tier.

The lithium-ion battery chemistry is the specification that changes the deployment calculus versus legacy VRLA designs. Li-Ion cells run cooler, tolerate higher ambient temperatures, deliver a longer service life, and consume a fraction of the footprint for equivalent runtime. In a dense rack environment where space and cooling are both constrained, that matters more than the acquisition price delta.

Key Features

• Double-Conversion (Online) Topology: Zero transfer time to battery — the inverter is always the source of output power. Transients, sags, surges, and frequency anomalies on the input side are fully isolated from connected equipment. For network core gear, storage arrays, or video management servers running 24/7, this is the topology you need, not line-interactive.
• 10KVA / 10KW Output at Unity Power Factor: Full 10,000W of usable capacity — no power factor derating. Many older UPS designs deliver 10KVA at 0.8 PF, meaning only 8KW of real work. The SRTL10KRM4UT's unity PF rating means the nameplate number is the actual available load budget for modern server and switch loads.
• Lithium-Ion Battery Chemistry: Compared to traditional VRLA batteries, Li-Ion handles a wider temperature range and retains capacity over more charge cycles. For installations where battery swap logistics are expensive — remote sites, sealed server rooms, tall rack columns — the extended service life reduces lifecycle cost and maintenance burden meaningfully.
• 208/240V Input and Output (40–70 Hz Input Range): The wide 40–70 Hz input frequency window accommodates generator input without frequency mismatch faults — critical for sites where the UPS is downstream of a diesel or natural gas generator. Output is regulated 208/240V at 50 or 60 Hz regardless of input condition.
• NEMA L6-20R and L6-30R Output Receptacles: Both 20A and 30A locking outlet types are provided, matching standard 208/240V PDU and server distribution infrastructure. No adapters required for typical data center or security operations center wiring.
• Emergency Power Off (EPO) Support: Hardwired EPO input allows facility safety systems or manual emergency shutoff panels to cut UPS output instantly — a requirement in many commercial building codes and NEC-governed data room installations. Integrate directly with your building's emergency shutdown circuit.
• 1,410 Joule Surge Energy Rating: Substantial surge suppression built into the output stage. While double-conversion topology already isolates most transients via the AC-DC-AC conversion path, the 1,410J rating provides an additional layer of protection for downstream equipment against severe transient events.
• Output THD ≤5% at Full Load: Clean sine wave output with low harmonic distortion keeps sensitive loads — particularly switching power supplies with active PFC — operating within specification. A UPS that pumps high-THD power into active-PFC PSUs can cause nuisance trips or degraded efficiency; the SRTL10KRM4UT's 5% THD ceiling avoids that failure mode.
• 3:1 Crest Factor Tolerance: The inverter handles loads with high peak-to-RMS current ratios without clipping or shutdown. Relevant when powering mixed loads that include laser printers, motor-driven equipment, or high-inrush server PSUs alongside standard IT gear.
• Audible Alarm Modes — On Battery and Low Battery: Distinct audible alerts for on-battery operation and low-battery threshold give operators clear status without requiring a monitoring console connection. Useful in environments where the UPS may not be network-monitored during a power event.
• 55 dB Noise Level: Measured at 55 dB, the SRTL10KRM4UT is deployable in semi-open environments or operations rooms without becoming a noise nuisance. Not silent, but within acceptable range for most server room or wiring closet installations where HVAC already sets the ambient noise floor.

Integration & Compatibility

The SRTL10KRM4UT operates on 208/240V single-phase infrastructure, which is standard in North American commercial and light-industrial electrical rooms. The unit fits standard 4-post server racks and enclosures in 4U, and the rack/tower convertible form factor allows standalone tower deployment during pre-racking staging or in environments without a rack cabinet.

The EPO terminal integrates with facility-level emergency power off systems per NEC Article 645 requirements for IT equipment rooms. Verify your EPO wiring polarity and contact type against APC's installation documentation before commissioning — EPO miswiring is a common commissioning error on double-conversion units.

For network infrastructure and security operations environments running surveillance servers, NVR arrays, or access control head-end equipment on 208V circuits, the SRTL10KRM4UT provides the runtime buffer and isolation quality needed to protect writes-in-progress and gracefully shut down recording servers during extended outages. Pair with APC's network management card options for SNMP/Modbus integration into your BMS or monitoring platform.

Review your UPS selection and sizing guide before committing to load capacity — accurate load measurement is the most common step skipped when specifying a 10KVA unit.

Frequently Asked Questions

Q: What is the difference between double-conversion (online) topology and line-interactive, and why does it matter for the SRTL10KRM4UT?

A: In double-conversion topology, all output power runs through the inverter continuously — the inverter is always on, not just during a power event. This means there is zero transfer time to battery and complete isolation from input power quality issues (sags, surges, frequency variation). Line-interactive UPS units switch to battery only when input falls out of range, leaving a brief transfer gap. For critical servers, storage arrays, and security infrastructure, double-conversion eliminates that gap and decouples your equipment from utility anomalies entirely.

Q: Can the SRTL10KRM4UT run on generator input?

A: Yes. The wide input frequency acceptance range of 40–70 Hz accommodates the frequency instability typical of diesel generators under varying load. The double-conversion topology further isolates output frequency from input variation, delivering a stable 50 or 60 Hz output regardless of generator frequency drift.

Q: What outlet types does the SRTL10KRM4UT provide, and will they work with standard PDU connections?

A: The unit provides NEMA L6-20R (20A locking) and NEMA L6-30R (30A locking) receptacles, both at 208/240V. These match standard North American 208V PDU and direct server connections. No adapters are required for typical commercial data center or security operations center wiring using L6-series connectors.

Q: Is the SRTL10KRM4UT rack-mountable, and what rack space does it require?

A: Yes. The SRTL10KRM4UT installs in a standard 19-inch rack in 4U of rack space. It is also convertible to tower orientation for standalone floor or shelf deployment, which is useful during staging or in environments without a rack enclosure.

Q: What is Emergency Power Off (EPO) and does the SRTL10KRM4UT support it?

A: EPO is a hardwired input that allows a facility's emergency shutdown system or a manual EPO switch to cut UPS output power immediately — a common requirement in commercial data rooms under NEC Article 645. The SRTL10KRM4UT includes EPO support, allowing direct integration with your building's emergency shutdown circuit.

Q: What is the output Total Harmonic Distortion (THD) of the SRTL10KRM4UT, and why does it matter?

A: Output THD is rated at 5% or less under full load. Low THD is important when powering server PSUs with active power factor correction (active PFC). High-THD UPS output can cause active-PFC power supplies to behave erratically or trip — the 5% ceiling on the SRTL10KRM4UT keeps connected equipment within its input specification.

Jerry Tildsen

The SRTL10KRM4UT is the unit I recommend when a customer has outgrown line-interactive protection and needs to hold a 10KW critical load through the kind of generator startup transients and utility frequency drift that kills cheaper UPS topologies. The double-conversion architecture and 40–70 Hz input window are the two specs that separate this from the commodity rack UPS market — together, they make it genuinely generator-friendly in a way many 10KVA units are not.

Technical Highlights:

• Unity Power Factor (10KVA = 10KW): No derating — every amp of nameplate capacity is available as real watts. On a 10KVA legacy 0.8 PF unit, you'd cap out at 8KW. The SRTL10KRM4UT's full 10,000W output budget is the actual number you can load plan against.
• 1,410J Surge Energy Rating + ≤5% Output THD: The surge suppression handles transient events that slip past the conversion stage, while the clean sine wave output keeps active-PFC server PSUs in spec. Both specs matter when you're powering a dense rack of switching supplies with mixed inrush profiles.
• Lithium-Ion Chemistry in a 4U Footprint: Li-Ion runs longer between replacements and tolerates higher rack temperatures than VRLA. In a sealed security server room or edge data closet where you can't easily roll a service truck, that reduced maintenance cycle is real operational value.

Deployment Considerations:

• Verify your facility's input circuit is sized for the SRTL10KRM4UT's inrush and steady-state draw at full load on a 208V or 240V circuit before commissioning. A 10KW online UPS at full load will draw well over 40A on a 208V single-phase feed — confirm breaker and conductor sizing in advance.
• EPO wiring is the most common commissioning error on double-conversion units — confirm contact type (normally open vs. normally closed) and wiring polarity against APC's installation documentation before connecting to the building's emergency shutdown circuit. A miswired EPO can cause an unintended shutdown during startup testing.

This unit is well matched to a security operations center or NVR head-end room running 208V infrastructure where you need full load isolation from a noisy utility feed or generator, and where battery maintenance windows are infrequent. If your load is under 5KW or you're on a 120V single-phase circuit, size down — this is a 208/240V-only, high-density rack unit and that overhead isn't free.