A single power outage can corrupt months of data on your NAS in seconds. I learned this the hard way when a brief blackout wiped out a RAID array I had spent weeks building, and that experience sent me on a mission to find the best UPS battery backup for NAS devices that money can buy.
After testing dozens of units across multiple NAS setups ranging from a modest 2-bay Synology to a power-hungry 8-bay QNAP, I narrowed the field down to eight models that actually deliver reliable power protection. The right UPS for NAS use goes beyond just keeping the lights on during a blackout. It needs USB communication for automatic safe shutdown, enough runtime to ride through brief outages, and surge protection that guards against the voltage spikes that follow.
In this guide, I walk you through each pick with real hands-on experience, covering everything from budget options for a home NAS to rack-mount units for small business setups. Whether you run a Synology, QNAP, TrueNAS, or UGREEN NAS, one of these eight UPS units will keep your data safe.
Table of Contents
Top 3 Picks for Best UPS for NAS (October 2026)
Best UPS Battery Backups for NAS in 2026
| Product | Specifications | Action |
|---|---|---|
 CyberPower CP1500PFCLCD |
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 APC Back-UPS Pro BR1500MS2 |
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 APC Back-UPS Pro BX1500M |
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 CyberPower CP850PFCLCD |
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 APC Back-UPS BE600M1 |
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 Eaton Tripp Lite SMART1500LCDT |
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 CyberPower CP1000AVRLCD |
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 CyberPower OR1500LCDRT2U |
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Check Latest Price |
1. CyberPower CP1500PFCLCD – Best Overall UPS for NAS
CyberPower CP1500PFCLCD PFC Sinewave UPS Battery Backup and Surge Protector
1500VA/1000W
PFC Sinewave
12 Outlets
Line-Interactive AVR
Color LCD
Pros
- PFC sine wave output safe for PFC power supplies
- 12 outlets with 6 on battery backup
- Color LCD panel for real-time monitoring
- AVR corrects brownouts without battery drain
- $500000 connected equipment guarantee
- USB-C and USB-A charging ports
Cons
- Heavy at nearly 25 pounds
- Some users report fan noise under load
I have run the CyberPower CP1500PFCLCD on my main 4-bay Synology NAS for over two years, and it has handled everything nature threw at it. From brief flickers to extended outages lasting 30 minutes, this unit never missed a beat. The PFC sine wave output is the standout feature here, because many modern NAS power supplies use active power factor correction that requires clean sine wave power to function properly.
What sold me on this model is the color LCD panel. It shows real-time wattage draw, battery capacity, estimated runtime, and voltage input all at a glance. When my NAS draws around 45 watts idle and spikes to 80 watts during heavy drive activity, I can see exactly what the UPS is handling. With over 11,000 reviews and a 4.6-star rating, this is the most battle-tested UPS for NAS on the market.
The 1500VA/1000W capacity gives you plenty of headroom. I connected my NAS, a network switch, and my router to the battery-backed outlets and still had capacity to spare. In my testing, the CP1500PFCLCD provided roughly 40 minutes of runtime for my NAS setup drawing about 70 watts combined. That is more than enough time for a safe automatic shutdown via USB.
The Automatic Voltage Regulation feature is something I did not appreciate until I lived in an area with frequent brownouts during summer. AVR corrects minor voltage dips and spikes without switching to battery power at all, which extends battery life significantly. The one downside is the weight, at nearly 25 pounds, and some users report fan noise when the unit is under heavy load. I found the fan barely audible in my office setup, but it is worth noting if your NAS sits in a quiet bedroom.
Compatible NAS Models and Setup
The CP1500PFCLCD works seamlessly with Synology DSM, QNAP QTS, and TrueNAS through standard USB HID communication. Synology recognizes it instantly when you plug in the included USB cable, and the UPS server package detects power events within seconds. I confirmed compatibility with Synology DS920+, DS923+, QNAP TS-453, and TrueNAS Scale running on custom hardware.
For multi-device setups, the 12 outlets mean you can protect your NAS, switch, router, and even a small monitor on the same unit. Just remember that only six outlets have battery backup while the other six are surge-only, so plan your connections accordingly.
Runtime Expectations by NAS Size
A 2-bay NAS drawing 25-35 watts will run for approximately 60-75 minutes on this UPS. A 4-bay NAS pulling 40-60 watts gets about 35-50 minutes of runtime. For an 8-bay NAS drawing 80-120 watts, expect 15-25 minutes, which is still plenty of time for a safe shutdown.
I recommend setting your NAS to enter safe mode after 5 minutes on battery power. This gives you a comfortable margin while preserving battery capacity for situations where power returns quickly.
2. APC Back-UPS Pro BR1500MS2 – Best Pure Sine Wave UPS for NAS
APC BR1500MS2 Pure Sine Wave UPS Battery Backup & Surge Protector
1500VA/900W
Pure Sine Wave
10 Outlets
AVR
User-Replaceable Battery
Pros
- True pure sine wave output
- 73 minutes runtime at 100W
- Coax and Ethernet surge protection
- LCD shows runtime and battery health
- USB-C and USB-A charging ports
- User-replaceable battery extends product life
Cons
- Heavier at 27.6 pounds
- 16-hour battery charge time
- Higher price point than competitors
The APC Back-UPS Pro BR1500MS2 is the UPS I recommend when someone wants APC reliability with pure sine wave output. I tested this unit with a QNAP TVS-871 that has an active PFC power supply, and the pure sine wave output kept it running flawlessly through simulated power outages. APC rates it for up to 73 minutes of runtime at 100W, which is among the best in this capacity class.
What sets the BR1500MS2 apart from cheaper APC models is the inclusion of coax and Ethernet surge protection. If your NAS connects to your network via Ethernet, having that dataline surge protection adds an extra layer of defense against lightning-induced surges that can travel through network cables. The LCD panel displays estimated runtime, load wattage, and battery health, giving you the same monitoring depth as the CyberPower.
The user-replaceable battery is a feature I value highly. APC uses the APCRBC163 battery cartridge, which means when the battery degrades after 3-5 years, you swap it out yourself instead of buying a whole new UPS. This extends the effective lifespan significantly and reduces long-term ownership cost. The 3,456 reviews averaging 4.5 stars confirm that users are satisfied with long-term reliability.
The main trade-offs are weight and charge time. At 27.6 pounds, this is the heaviest unit in the lineup, and the 16-hour battery charge time means you need patience after a deep discharge. I also noticed the price sits higher than the CyberPower CP1500PFCLCD despite offering slightly lower wattage capacity at 900W versus 1000W. However, if you specifically want APC brand reliability and pure sine wave output, the premium is justified.
Active PFC Compatibility
The BR1500MS2 is specifically designed to work with active PFC power supplies found in many modern NAS devices and computers. Cheaper simulated sine wave UPS units can cause PFC power supplies to shut down unexpectedly during power transfer, but the pure sine wave output of this APC model eliminates that risk entirely.
I verified this by testing with a Synology DS1622+ that has a PFC power supply. The transfer from mains to battery was seamless with zero interruption to NAS operation, confirming the active PFC compatibility claim.
Battery Replacement Planning
Plan to replace the battery cartridge every 3 to 5 years depending on your power environment. The APCRBC163 replacement battery is readily available and straightforward to install through the battery door on the front of the unit. No tools are required for the swap.
The LCD will display battery health status, giving you advance warning before replacement is needed. I recommend checking battery health quarterly through the LCD panel or APC PowerChute software.
3. APC Back-UPS Pro BX1500M – Best Value UPS for NAS
APC BX1500M UPS Battery Backup & Surge Protector for Computers, Electronics
1500VA/900W
10 Outlets
Simulated Sine Wave
AVR
ENERGY STAR Certified
Pros
- Excellent price-to-performance ratio
- 68 minutes runtime at 100W
- ENERGY STAR certified for efficiency
- Built-in coax and Ethernet surge protection
- LCD display with real-time status
- $75
- 000 equipment protection warranty
Cons
- Simulated sine wave not ideal for PFC power supplies
- 19 minutes runtime at full load
- Heavy at 24.25 pounds
The APC Back-UPS Pro BX1500M is the best value UPS for NAS in this lineup, and with over 13,000 reviews, it is also one of the most popular. I deployed this unit in my brother’s home office where it protects a Synology DS220+ and a router, and it has performed flawlessly through multiple outages over the past 18 months.
What makes the BX1500M such a strong value is that you get 1500VA/900W capacity, AVR, an LCD display, and ENERGY STAR certification at a price point notably below the pure sine wave models. The 68 minutes of runtime at 100W means most NAS setups will have plenty of time for graceful shutdown. For a 2-bay NAS drawing 30 watts, expect well over an hour of runtime.
The key difference from the BR1500MS2 is the output waveform. The BX1500M uses a simulated sine wave rather than pure sine wave. For most NAS devices this is completely fine, as I confirmed testing with Synology DS220+, DS420+, and a Terramaster F2-422. However, if your NAS has an active PFC power supply, you should step up to a pure sine wave model to avoid potential shutdown during power transfer.
I appreciate that APC includes coaxial and Ethernet surge protection on the BX1500M, matching the more expensive BR1500MS2. The LCD shows battery charge level, estimated runtime, and load capacity, which I check every few weeks to make sure everything is operating normally. The ENERGY STAR certification means it draws minimal phantom power when not in use, keeping electricity costs down.
Best Use Cases for the BX1500M
This unit shines for home and small office NAS setups with 2 to 4 bays. It is ideal for Synology DS220+, DS420+, DS920+, QNAP TS-230, and similar devices that do not use active PFC power supplies. I also recommend it for protecting a NAS plus router combo, as the 10 outlets give you room for both.
For 6-bay and larger NAS devices with heavier power draw, consider stepping up to the CyberPower CP1500PFCLCD or APC BR1500MS2 for the extra headroom and pure sine wave output.
NAS Software Integration
The BX1500M connects to your NAS via the included USB cable, enabling automatic shutdown through Synology DSM, QNAP QTS, or TrueNAS. In Synology DSM, navigate to Control Panel, Hardware and Power, and then UPS to configure continuous UPS status monitoring and timed auto-shutdown.
I recommend setting the NAS to enter safe mode after 5 minutes on battery power and to shut down after 10 minutes. This two-stage approach preserves data while maximizing runtime if power returns quickly.
4. CyberPower CP850PFCLCD – Best Compact PFC Sine Wave UPS
CyberPower CP850PFCLCD PFC Sinewave UPS Battery Backup and Surge Protector
850VA/510W
PFC Sine Wave
10 Outlets
Mini-Tower
AVR
UL Certified
Pros
- PFC sine wave output in compact form factor
- Mini-tower design saves space
- Color LCD panel for monitoring
- AVR extends battery life
- 10 outlets with good distribution
- Lighter at 14.9 pounds
Cons
- Lower 510W capacity limits NAS size
- Only 5 battery-backed outlets
- Limited stock availability
The CyberPower CP850PFCLCD is the compact sibling of my top pick, offering the same PFC sine wave technology in a smaller, lighter package. I tested this unit with a 2-bay Synology DS220+ and found it to be the perfect match, providing clean power and reliable USB communication in a footprint that fits on a shelf next to the NAS.
At 14.9 pounds and measuring just 10.4 x 3.9 x 9.1 inches, this is the most space-efficient PFC sine wave UPS in the lineup. The mini-tower design tucks neatly beside a NAS without taking up much room, which matters if your setup lives in a closet or on a small desk. Despite the compact size, you still get a color LCD panel showing battery status, runtime estimates, and load information.
The 850VA/510W capacity is the main limitation to understand. This unit is designed for a 1 or 2-bay NAS drawing up to about 50 watts. I measured approximately 25 minutes of runtime with my test 2-bay NAS and router drawing a combined 40 watts. That is adequate for safe shutdown but will not keep your NAS running through extended outages.
The PFC sine wave output is the real selling point at this size and price. Finding pure or PFC sine wave output in a compact, affordable UPS is uncommon. Most small units use simulated sine wave, which can cause issues with PFC power supplies. The CP850PFCLCD solves that problem without requiring you to buy a full-size tower UPS.
When to Choose the CP850PFCLCD
This is my top recommendation for 1-bay and 2-bay NAS owners who want sine wave protection without the bulk of a 1500VA unit. It pairs perfectly with Synology DS120, DS220+, DS223, QNAP TS-133X, and similar compact NAS devices. The AVR feature handles minor voltage fluctuations without draining the battery, which is especially valuable in older buildings with unstable wiring.
Limitations to Consider
The 510W capacity means you should not connect high-draw devices alongside your NAS. Stick to the NAS and perhaps a router on the battery-backed outlets. Also note that stock availability fluctuates, so if you find it in stock, do not hesitate. The 894 reviews averaging 4.4 stars indicate solid satisfaction among owners.
If you plan to upgrade to a 4-bay NAS in the near future, consider spending a bit more on the CP1500PFCLCD for the extra capacity headroom.
5. APC Back-UPS BE600M1 – Best Budget UPS for Small NAS
APC BE600M1 UPS Battery Backup & Surge Protector for Computer, Router, NAS
600VA/330W
7 Outlets
Compact Design
USB Charging
5 Battery Backup Outlets
Pros
- Most affordable option in the lineup
- Compact and lightweight at 7.5 pounds
- 23 minutes runtime at 100W
- Best seller in UPS category
- USB charging port for mobile devices
- Easy battery replacement
Cons
- Lower 330W capacity for small NAS only
- Simulated sine wave output
- Only 5 battery-backed outlets
- No LCD display
The APC Back-UPS BE600M1 is the number one best seller in the entire UPS category on Amazon, with nearly 29,000 reviews and a 4.5-star rating. I picked one up for a budget 2-bay NAS build, and it does exactly what a NAS UPS should do at the lowest possible price point: it keeps your NAS running long enough for a safe shutdown.
This is a no-frills unit. There is no LCD display, no pure sine wave output, and the 600VA/330W capacity limits you to smaller NAS devices. But the BE600M1 includes a USB cable for NAS communication, supports automatic shutdown through Synology DSM and QNAP QTS, and provides 23 minutes of runtime at 100W load. For a 2-bay NAS drawing 25-30 watts, you will see roughly 40-50 minutes of runtime.
At just 7.5 pounds and measuring 10.79 x 4.13 x 5.47 inches, this is the lightest and most portable UPS in the lineup. I set mine on a shelf right behind a Synology DS218, and it takes up minimal space. The compact form factor makes it ideal for apartments, dorm rooms, or anywhere space is tight.
The simulated sine wave output means this unit is best paired with NAS devices that use standard power supplies without active PFC. I confirmed trouble-free operation with Synology DS218, DS220j, and QNAP TS-230. If your NAS has an active PFC power supply, I recommend stepping up to the CyberPower CP850PFCLCD for sine wave protection.
Ideal NAS Pairings
The BE600M1 pairs perfectly with entry-level 1-bay and 2-bay NAS devices like the Synology DS120j, DS220j, DS218, and QNAP TS-130. It is also a good match for protecting a router alongside a small NAS, since the five battery-backed outlets can cover both devices. The 1.5A USB port is handy for charging a phone during an outage.
Setting Up Automatic Shutdown
Connect the included USB cable from the BE600M1 to your NAS, then configure shutdown in your NAS operating system. In Synology DSM, go to Control Panel, then Hardware and Power, then UPS. Enable UPS support and set the NAS to enter safe mode after a few minutes on battery.
The BE600M1 communicates using standard USB HID protocol, which means no driver installation is needed on most NAS systems. I had it working with my Synology in under two minutes from unboxing.
6. Eaton Tripp Lite SMART1500LCDT – Best Rack-Mountable UPS for NAS
Eaton Tripp Lite SMART1500LCDT 1500VA UPS 900W 10 Outlets 650 Joules AVR
1500VA/900W
10 Outlets
Tower Form
AVR
LCD Display
650J Surge
Pros
- 900W capacity handles demanding NAS setups
- AVR corrects brownouts and overvoltages
- LCD shows runtime wattage load and battery status
- Ethernet and telephone dataline protection
- User-replaceable batteries
- $250
- 000 connected equipment insurance
Cons
- Simulated sine wave output
- 10.7 minutes runtime at full load
- Lower surge protection rating at 650 joules
The Eaton Tripp Lite SMART1500LCDT brings a different brand into the mix, and after testing it with a TrueNAS server, I appreciate the industrial build quality that Tripp Lite is known for. Eaton acquired Tripp Lite, and their combined engineering shows in the solid construction and detailed LCD readout that displays wattage load, battery runtime, input voltage, and AVR status simultaneously.
This unit provides 1500VA/900W of capacity with AVR that corrects brownouts and overvoltages between 92V and 150V without touching battery reserves. I found this particularly valuable during summer months when air conditioning loads cause voltage sags. The NAS kept running without interruption while the UPS silently corrected the voltage.
The 10 outlets give you generous connectivity, and the included six-foot power cord with a right-angle plug makes it easy to position against a wall. Ethernet RJ45 and telephone RJ11 dataline protection are included, which adds value if your NAS connects to network infrastructure that could carry surge voltage. The 2,197 reviews averaging 4.2 stars reflect a solid but slightly lower satisfaction rate compared to the APC and CyberPower options.
The main drawback is the 10.7 minutes of runtime at full 900W load. For a NAS drawing 50-80 watts, you will get substantially more runtime, but heavy setups with multiple drives will see shorter backup windows. The simulated sine wave output also means this unit is not ideal for NAS devices with active PFC power supplies.
TrueNAS and Linux Compatibility
I tested the SMART1500LCDT extensively with TrueNAS Scale and found it works perfectly with Network UPS Tools, the standard UPS monitoring daemon on Linux. The USB connection is recognized automatically, and the NUT driver provides detailed status information including input voltage, battery charge, and estimated runtime.
For TrueNAS users, enable the UPS service in the web interface, select the USB connection, and configure shutdown timers. I set my TrueNAS server to begin shutdown after 3 minutes on battery, which provides ample time while protecting data integrity.
Rack and Cabinet Installation
While the SMART1500LCDT is a tower form factor, its dimensions make it suitable for placement in the bottom of a network cabinet or on a shelf in a server rack. The rugged ABS and metal construction can handle the environment better than plastic-only units. If you need a formal rack-mount form factor, consider the CyberPower OR1500LCDRT2U later in this guide.
7. CyberPower CP1000AVRLCD – Best Mid-Range UPS for Home NAS
CyberPower CP1000AVRLCD Intelligent LCD UPS Battery Backup
1000VA/600W
9 Outlets
Mini-Tower
Simulated Sine Wave
AVR
ENERGY STAR
Pros
- Sweet spot capacity for 2-4 bay NAS
- 9 outlets with good distribution
- ENERGY STAR certified for efficiency
- AVR prevents unnecessary battery drain
- LCD panel shows runtime and load
- Free PowerPanel management software
- $350
- 000 equipment guarantee
Cons
- Simulated sine wave not ideal for PFC supplies
- Limited runtime at high load
- Older product design
The CyberPower CP1000AVRLCD occupies a nice middle ground between budget and premium options. I tested it with a 4-bay Asustor NAS and a network switch, and the 1000VA/600W capacity handled both devices with room to spare. With over 4,500 reviews and a 4.5-star rating, this model has proven itself reliable over many years on the market.
This is the model I recommend when the BE600M1 is too small but the CP1500PFCLCD is more than you need. The mini-tower form factor measures 10.2 x 3.9 x 9 inches, making it compact enough to sit alongside your NAS without dominating the space. The LCD panel displays runtime, battery capacity, and load capacity in a clear, rotating display.
The AVR feature is particularly well-implemented on this model. During my testing, I simulated brownouts using a variac and watched the CP1000AVRLCD boost the voltage back to safe levels without switching to battery power. This means the battery is preserved for actual outages rather than being drained by minor voltage fluctuations, which extends battery life significantly.
The nine outlets give you five with battery backup and four surge-only, which I found to be a practical split. My NAS and network switch went on battery backup, while less critical peripherals used the surge-only outlets. The included PowerPanel Personal Edition software provides detailed monitoring on Windows, though NAS communication works through standard USB HID without any additional software.
PowerPanel Software and NAS Integration
The free PowerPanel software offers detailed monitoring and logging on Windows systems, showing power events, battery health trends, and runtime history. For NAS integration, the USB connection enables automatic shutdown through Synology, QNAP, and TrueNAS without needing the PowerPanel software running separately.
I recommend using the NAS built-in UPS management tools for shutdown automation and keeping PowerPanel installed on a Windows PC for monitoring and firmware updates if you want detailed logging.
Who Should Buy the CP1000AVRLCD
This model is ideal for home users with a 2 to 4-bay NAS who want solid protection without paying for sine wave output they may not need. It works with Synology DS420+, DS423, QNAP TS-451, Asustor AS5304T, and similar mid-range devices that use standard power supplies.
If your NAS uses an active PFC power supply, skip this model and choose the CP1500PFCLCD or CP850PFCLCD instead for their PFC-compatible sine wave output.
8. CyberPower OR1500LCDRT2U – Best Rack/Tower UPS for Business NAS
CyberPower OR1500LCDRT2U Smart App LCD UPS Battery Backup
1500VA/900W
2U Rack/Tower
8 Outlets
1840J Surge
Remote Management
Metal Enclosure
Pros
- 2U rack/tower form factor for flexible installation
- Highest surge protection at 1840 joules
- 18 minutes runtime at full load
- Remote management capability with optional card
- Metal enclosure for durability
- $300
- 000 connected equipment guarantee
- Energy Star certified
Cons
- Highest price in the lineup
- Heavy at 48.4 pounds
- Lower review count at 130 reviews
The CyberPower OR1500LCDRT2U is the most professional-grade UPS in this lineup, designed for small business NAS deployments and rack-mounted environments. I deployed this unit in a small business rack protecting a QNAP TS-873A and a network switch, and the 2U rack/tower form factor integrated cleanly into the existing infrastructure.
What makes this model stand out is the combination of 1840 joules of surge protection, the highest in this lineup, and the remote management capability. With an optional remote management card, you can monitor and control the UPS over the network, which is essential for business environments where the server room is not always accessible.
The metal enclosure feels distinctly more robust than the plastic housings on consumer models. In a rack environment, this matters because the UPS needs to withstand vibration, temperature fluctuations, and the occasional bump during maintenance. The 18 minutes of runtime at full 900W load is the best runtime specification in this lineup, which gives business users confidence that their NAS will survive extended outages.
The LCD screen provides comprehensive information including runtime in minutes, battery status, and detailed power conditions. The included PowerPanel Business Edition software supports more advanced features than the Personal edition, including SNMP management, event scheduling, and email notifications for power events.
Network UPS Tools and Multi-NAS Setups
The OR1500LCDRT2U works excellently with Network UPS Tools for protecting multiple NAS devices from a single UPS. I set up NUT in TrueNAS to act as a UPS server, with the UPS connected via USB. Other NAS devices and servers on the network connect to the TrueNAS NUT server as clients, receiving shutdown signals when the UPS reports low battery.
This configuration is ideal for business environments with multiple servers. One OR1500LCDRT2U can protect an entire small rack of equipment while coordinating orderly shutdowns across all connected systems.
Business Deployment Considerations
The 48.4-pound weight means you need a sturdy rack or shelf. In a 2U rack configuration, use rail mounts rated for at least 50 pounds. The remote management card is a worthwhile investment for business deployments, allowing you to monitor power conditions and receive alerts without being physically present.
While the 130-review count is lower than other models, the 4.6-star rating is the highest tied with the CP1500PFCLCD, indicating strong satisfaction among business users. The limited stock status also suggests this is a specialized product aimed at the business market rather than consumer retail.
How to Choose the Right UPS for Your NAS?
Choosing the right UPS for NAS comes down to five key factors. I will walk you through each one based on my experience testing these units across different NAS configurations.
VA Rating and Wattage: Understanding the Numbers
The most common confusion I see is the difference between VA and watts. VA, or volt-amps, is the apparent power rating, while watts represent real power. Most UPS units have a power factor of 0.6 to 0.67, meaning a 1500VA UPS typically delivers 900 to 1000 watts. Always check the watt rating, because that is what your NAS actually draws.
To size your UPS, add up the wattage of everything you plan to connect. A 2-bay NAS draws 20-35 watts, a 4-bay NAS draws 40-70 watts, and an 8-bay NAS draws 80-150 watts. Add 15-25 watts for a router and switch if you plan to protect those too. Buy a UPS rated for at least 1.5 times your total load to ensure adequate runtime.
Sine Wave Type: Why It Matters for NAS
UPS units produce either pure sine wave, PFC sine wave, or simulated sine wave output. Pure and PFC sine wave output matches the clean power from your wall outlet, which is required for NAS devices with active PFC power supplies. Simulated sine wave approximates the waveform using stepped output, which works fine for standard power supplies but can cause shutdowns with PFC-equipped devices.
As a rule of thumb, most 2-bay NAS devices work fine with simulated sine wave. For 4-bay and larger NAS devices, check your power supply specifications. If it mentions active PFC, choose a pure or PFC sine wave UPS like the CyberPower CP1500PFCLCD or APC BR1500MS2.
Runtime: How Long Do You Really Need?
For NAS protection, you do not need hours of runtime. You need enough time for a safe shutdown, which takes 2-5 minutes on most NAS systems. A UPS that provides 15-30 minutes of runtime at your NAS load is more than sufficient. Buying a much larger UPS for extended runtime has diminishing returns, since your NAS will shut down automatically regardless.
I recommend setting your NAS to enter safe mode after 5 minutes on battery and shut down after 10 minutes. This gives you a comfortable safety margin without wasting battery capacity.
USB Communication: Essential for NAS Protection
USB connectivity is non-negotiable for a NAS UPS. Without it, your NAS cannot detect power outages and will not perform an automatic safe shutdown. Every UPS in this guide includes USB communication via HID protocol, which works with Synology DSM, QNAP QTS, TrueNAS, and most other NAS operating systems without additional drivers.
Make sure to connect the USB cable between the UPS and your NAS, then configure shutdown settings in your NAS control panel. I see too many users who buy a quality UPS but never connect the USB cable, defeating the entire purpose of NAS-specific power protection.
Automatic Voltage Regulation: Handling Brownouts
AVR is a feature that corrects minor voltage fluctuations without switching to battery power. If you live in an area with frequent brownouts, voltage sags, or unstable power, AVR extends battery life significantly by handling these minor events without draining the battery. Every UPS in this guide includes AVR, which I consider essential for any NAS deployment.
Without AVR, every minor voltage dip triggers a battery cycle, which degrades the battery faster and shortens its lifespan. With AVR, the UPS simply boosts or trims the voltage in real-time, keeping the battery fresh for actual power outages.
Frequently Asked Questions
Which uninterruptible power supply (UPS) is best for a NAS?
The CyberPower CP1500PFCLCD is the best overall UPS for NAS devices, offering 1500VA/1000W capacity, PFC sine wave output, AVR, and USB communication for automatic safe shutdown. It works with Synology, QNAP, TrueNAS, and UGREEN NAS devices.
Which APC UPS is best for a NAS?
The APC Back-UPS Pro BR1500MS2 is the best APC UPS for NAS, featuring 1500VA/900W capacity with pure sine wave output and 73 minutes of runtime at 100W. For a budget option, the APC Back-UPS BE600M1 is ideal for small 1-2 bay NAS devices.
Should a NAS be on a UPS?
Yes, any NAS should be connected to a UPS. A single power outage during a write operation can corrupt RAID arrays and destroy data. A UPS provides battery backup for safe shutdown and surge protection against voltage spikes that can damage NAS hardware.
What is the best UPS for a Synology NAS?
The CyberPower CP1500PFCLCD and APC Back-UPS Pro BX1500M are both excellent choices for Synology NAS. Both connect via USB for automatic shutdown through Synology DSM and provide enough runtime for a safe shutdown during power outages.
Conclusion
After testing all eight units across multiple NAS configurations, the CyberPower CP1500PFCLCD remains my top pick for the best UPS for NAS in 2026. Its combination of PFC sine wave output, 1500VA capacity, color LCD, and proven reliability across more than 11,000 reviews makes it the safest bet for protecting your data.
For budget-conscious users with a small 1 or 2-bay NAS, the APC Back-UPS BE600M1 delivers essential protection at the lowest price. Business users with rack-mounted setups should look at the CyberPower OR1500LCDRT2U for its rack form factor and remote management capabilities. Whatever your NAS setup, do not wait for a power outage to teach you why a UPS matters.