Best UPS for UniFi Rack (2026): Protecting UDM Pro & Active PFC Gear

UniFi's enterprise-grade gear—particularly the UDM Pro Max, UDM-SE, and USW Pro Max switches—uses Active PFC (Power Factor Correction) power supplies. These PSUs generally prefer clean, pure sine wave power, though modern designs are more tolerant than older generations.

This guide compares the major UPS options for UniFi deployments: APC, CyberPower, Eaton, and the UniFi UPS 2U. We also cover the growing availability of Lithium-Ion (LiFePO4) batteries and what they mean for long-term ownership costs.

Why Waveform Matters for Active PFC Gear

Before comparing products, let's clarify why waveform is relevant—without overstating the risk.

Simulated vs. Pure Sine Wave

When your UPS switches to battery, it generates AC power in one of two forms:

Simulated Sine Wave (Stepped): Cheaper to produce. The waveform looks like a jagged staircase. Works fine for basic electronics and many modern power supplies.

Pure Sine Wave: Matches the smooth, curved wave from your wall outlet. Preferred for sensitive electronics with Active PFC power supplies.

The Active PFC Consideration

The newer UniFi devices—especially the UDM-SE, UDM Pro Max, and USW Pro Max switches—use Active PFC in their power supplies.

When fed simulated sine wave from a budget UPS, Active PFC gear may:

• Experience instability or reboots during the transition to battery power
• Make clicking noises as the PSU handles the waveform transition
• Run less efficiently and generate more heat over time

That said, modern Active PFC power supplies are more robust than older designs. Many users report running simulated sine wave UPS units with UniFi gear without issues. The risk isn't instant failure—it's potential instability and reduced efficiency over time.

The Cost Reality

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Lead-Acid vs. Lithium-Ion: The 2026 Reality

Lithium-Ion batteries are changing the economics of UPS ownership. Here's what you need to know.

The Lead-Acid Reality

Traditional UPS units use Sealed Lead-Acid (SLA) batteries:

• Heavy (a 1500VA unit weighs 40–50 lbs)
• 3–5 year lifespan before capacity drops significantly
• Requires periodic replacement ($100–$200 per swap)

When people recommend an Eaton 5SC as a long-term investment, they're right about the unit—it can last 10+ years. But you'll replace the batteries 2–3 times.

The Lithium-Ion (LiFePO4) Advantage

Lithium-Iron Phosphate (LiFePO4) batteries are becoming more available:

• 8–10 year lifespan (vs. 3–5 for lead-acid)
• 40–50% lighter at equivalent capacity
• Faster recharge times

The catch? Dedicated LiFePO4 rackmount UPS units remain expensive. The Eaton 9PX Lithium (1500VA) typically runs $2,800–$3,400.

Total Cost of Ownership

For most homelabbers, the Eaton 5SC or 5PX G2 with planned battery replacements is the practical choice. Lithium makes sense for enterprise deployments where maintenance downtime has real costs.

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The Contenders: 2026 Standings

CyberPower: The Budget Option

Focus Model: CyberPower CP1500PFCLCD (Tower) or OR1500PFCRT2U (Rackmount)

Price: ~$240 (Tower) / ~$400 (Rack)

Waveform: Pure Sine Wave ✓

Rack Depth: ~15" (standard depth)

Outlets: NEMA 5-15R (standard US plugs—easy for beginners)

The Good:

• Cheapest entry into pure sine wave coverage
• Solid software (PowerPanel) for automated shutdowns
• Works well with NUT (Network UPS Tools) for UniFi integration
• Standard NEMA outlets work with any device

The History: Adhesive Quality Issues

Earlier revisions (Rev 1 and Rev 2) of the CP1500PFCLCD had documented issues with the yellow adhesive used to secure components to the circuit board.

Best For: Cost-conscious buyers who want pure sine wave without a major investment.

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APC: The Enterprise Standard

Focus Model: APC SMT1500C (Smart-UPS with SmartConnect)

Price: ~$500–$600

Waveform: Pure Sine Wave ✓

Rack Depth: ~17" (standard enterprise depth)

Outlets: NEMA 5-15R (standard US plugs)

The Good:

• Strong build quality and long unit lifespan
• Extensive ecosystem (network cards, battery packs)
• Works well with NUT for UniFi integration
• Trusted brand in enterprise environments

The Consideration: SmartConnect Cloud Fees

APC (owned by Schneider Electric) offers cloud-based management through SmartConnect:

The Standard plan is reasonably priced over 3 years. If you want full local control without any cloud, you'll need an optional Network Management Card (~$200+).

Best For: Corporate environments and users who want a trusted vendor with extensive support options.

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Eaton: The Prosumer Sweet Spot

Focus Model: Eaton 5SC1500 (Tower/Short Rack) or Eaton 5PX G2 (Premium Rack)

Price: ~$450 (5SC) / ~$1,200 (5PX G2 lead-acid) / ~$3,000 (9PX Lithium)

Waveform: Pure Sine Wave ✓

Rack Depth: ~16" (405mm)—shorter than enterprise 24"+ units, but still requires a standard-depth cabinet

Outlets: NEMA 5-15R (standard US plugs)

The Good:

• Industrial-grade DNA: Eaton is a major player in commercial/industrial power
• No subscription fees: Local management via USB or optional Network-M2 card
• Short depth (relative): At ~16", it's shorter than enterprise 24"+ units but still needs a standard cabinet
• 5PX G2 fan control: Fans turn off at less than 30% load—quiet relative to other rack units (though not silent)
• Scalability: 5PX supports external battery modules for extended runtime

The Secret Weapon: You can monitor Eaton units over USB with NUT (Network UPS Tools) on a Raspberry Pi. This provides free, local monitoring and graceful shutdown signals to your UniFi gateway—no cloud required.

Best For: Users who value long-term reliability and need short rack depth. The Eaton 5SC is the best balance of price, quality, and form factor for most UniFi racks.

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The UniFi Native Option

UniFi UPS 2U

Ubiquiti released their own rackmount UPS, and it deserves serious consideration for all-UniFi deployments:

Specs:

• 1.44kVA / 1000W capacity
• 4 backup outlets + 4 surge-only outlets (NEMA 5-15R on US model)
• 216Wh battery (~8 minutes at 500W half-load)
• Native integration with UniFi Network app
• Graceful Shutdown support for UNVR and UNAS (requires UniFi OS 4.4.3+)
• NUT compatibility for third-party devices

Price: ~$279 MSRP (may vary based on availability)

Rack Depth: ~11" (very shallow—fits almost any rack)

Outlets: NEMA 5-15R (standard US plugs on the US model)

View on Ubiquiti Store →

The Good:

• Single-pane-of-glass management: Monitor battery status, load, and runtime directly in the UniFi Network app
• Automatic Graceful Shutdown: When battery runs low, it signals UNVR and UNAS to safely shut down
• NUT support: Third-party devices can receive shutdown signals
• Ultra-shallow depth: Fits in the tightest racks
• User-replaceable batteries

Capacity Note: The 216Wh battery is roughly half the capacity of competing 1500VA units (which typically offer 400–500Wh). You get less runtime, but for most UniFi racks drawing 200–400W, 8–10 minutes is sufficient for graceful shutdown.

Verdict: For all-UniFi deployments—especially those with UNVR or UNAS—the UniFi UPS 2U offers the best ecosystem integration available. The Graceful Shutdown feature and native dashboard monitoring justify the tradeoffs in capacity and waveform. For mixed environments or maximum runtime, third-party Eaton units provide more capacity per dollar.

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Comparison: At a Glance

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Our Recommendations

The Budget-Conscious Choice

CyberPower CP1500PFCLCD (~$240)

Pure sine wave at the lowest price point. Plan for battery replacement every 3–4 years, and you'll get solid protection for your UniFi rack. Standard NEMA outlets make setup easy.

Shop CyberPower on Amazon →

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The Best Value Choice

Eaton 5SC1500 (~$450)

Industrial reliability, pure sine wave, no subscription fees, and short rack depth that fits where others won't. The best balance of price, quality, and form factor for most UniFi racks. Pair it with a Raspberry Pi running NUT for enterprise-grade monitoring.

Shop Eaton 5SC →

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The UniFi Ecosystem Choice

UniFi UPS 2U (~$279 MSRP)

If you're running an all-UniFi rack with UNVR or UNAS, the native integration is compelling. Graceful Shutdown protects your recordings and NAS data automatically.

Shop UniFi UPS →

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The Long-Term Investment

Eaton 5PX G2 (~$1,200 lead-acid)

For users who want premium build quality, whisper-quiet operation, and external battery expansion. The 5PX G2 is the prosumer ceiling for lead-acid. True Lithium options (Eaton 9PX Li at ~$3,000) make sense for enterprise deployments where maintenance downtime has real costs.

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Frequently Asked Questions

Does my UDM Pro really need a pure sine wave UPS?

Recommended but not mandatory. Pure sine wave eliminates compatibility concerns. However, modern Active PFC power supplies (including those in UniFi gear) are more tolerant than older designs. Many users run simulated sine wave UPS units without issues. Ubiquiti's own UPS uses simulated sine wave and is validated for their hardware.

Can I manage an Eaton UPS through the UniFi dashboard?

Not natively. However, you can use Network UPS Tools (NUT) on a Raspberry Pi or Linux server to monitor the Eaton UPS and trigger graceful shutdowns via SSH. This approach offers more flexibility than native integration and costs nothing beyond the Pi.

Why does rack depth matter?

Many home network cabinets and wall-mount racks are only 12–15" deep. Standard enterprise UPS units are often 17–24" deep and won't fit. The UniFi UPS 2U (~11") is specifically designed for shallow racks, while the Eaton 5SC (~16") fits standard-depth cabinets.

What about outlet types?

Most UPS units sold in the US use standard NEMA 5-15R outlets (regular wall plugs). The UniFi UPS 2U (US model) also uses NEMA outlets. Some international models use IEC C13 outlets, which require adapter cables for standard devices.

How long do UPS batteries last?

• Lead-Acid (most UPS units): 3–5 years
• Lithium-Ion (Eaton 9PX Li): 8–10 years

Always buy replacement batteries from reputable sources—cheap third-party batteries often have reduced capacity.

What size UPS do I need for a UniFi rack?

A typical UniFi small business setup with a UDM Pro, 24-port PoE switch, and a few APs draws 200–400W. A 1500VA/1000W UPS provides 10–20 minutes of runtime—enough for most outages or graceful shutdown.

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Match your UPS investment to your deployment. An all-UniFi rack benefits from the UniFi UPS integration. Mixed environments get more value from Eaton's reliability and form factor.