Guide 35 · UPS
Choosing a UPS for a Home Office NAS
A NAS needs both battery power and a supported way to learn that utility power has failed. Start with the exact NAS model, operating-system version and UPS connection type. Then check the time and power needed to reach the storage maker’s documented safe state.
On this page
- Start with compatibility, not the UPS brand
- Separate power delivery from the data path
- Understand the storage system’s safe state
- Include the dependencies that carry the signal
- Worked example: budget for the safe-state sequence
- Verify behavior without inventing a test
- Choose the guide for your equipment
- Sources
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The verdict
Choose a UPS only after checking the exact NAS pairing and shutdown path; a USB socket, brand name or sine-wave label alone does not establish automatic shutdown support.
See the store linkWhat we check
- Exact NAS and UPS compatibility
- USB data or supported network signaling
- Configured shutdown or safe-state trigger
- Runtime through the shutdown sequence
- Network dependencies for remote signaling
- Output requirements and battery-backed outlets
Drawing of backup power equipment.
Store link UPS
CyberPower CP1500PFCLCD PFC Sinewave UPS Battery Backup and Surge Protector
One listing to compare. Check its specs against the list above before you buy.
Maker's US pageCyberPower's US page lists it with Purchase Online.cyberpowersystems.com Checked
What owners reportOwners report it works with home server and NAS shutdown software and lasts for years with fresh batteries. Forum owners also say the batteries can give out with no warning from the unit.TrueNAS forum, Unraid forum, The FPS Review forum Checked
PriceAmazon sets it, and it changes. The button takes you to today's price.
Store linkPaid link
The unit named above, on Amazon.
Check price on AmazonHoldBackup earns a commission if you buy through this link. Amazon sets the price.
NAS shutdown compatibility: what each connection requires
| Criterion | DS923+ + CP1500PFCLCDDirect USB example | Synology network UPS server | SNMP UPS |
|---|---|---|---|
| Listing evidence | DS923+ list: CP1500PFCLCD is Vendor Recommended | Choose a listed UPS for the USB-connected Synology server | Check the NAS maker’s exact model and SNMP support |
| Outage signal | UPS USB data port → NAS USB port, directly | USB → server NAS → permitted client NAS over the local network | UPS network management interface → NAS over the network |
| Extra hardware | Use the data cable; USB hubs are unsupported by Synology | Connecting switch or hub must share UPS power | CP1500PFCLCD needs optional RMCARD205 for SNMP; not included in the base offer |
| Storage action | Configure DSM 7 Standby Mode and verify recognition | Configure the server, permitted clients and each client’s UPS support | Configure the supported network UPS mode and outage trigger |
| Still unverified | Your unit, firmware and actual safe-state behavior | Your server/client combination and notification path | Your management card, protocol settings and NAS pairing |
Synology’s live DS923+ list labels this model Vendor Recommended, not Tested by Synology. Its UPS power-off support field is unspecified. Manufacturer guidance checked Oct 9, 2026; HoldBackup has not tested these systems. Recheck the list for your NAS and firmware.
Start with compatibility, not the UPS brand
Select your NAS model in its manufacturer’s UPS compatibility tool and check the exact UPS variant, connection type and notes. Synology warns that hardware or firmware changes can affect compatibility. A brand appearing elsewhere on the list does not validate your pairing.
The store offer on this page is the CyberPower CP1500PFCLCD. In Synology’s DS923+ UPS list, this exact model is labeled Vendor Recommended, not Tested by Synology. That is a manufacturer-listed example, not a HoldBackup test or support for every NAS. The list does not specify UPS power-off support for this entry; confirm your hardware, firmware and required behavior.
Separate power delivery from the data path
Plan two connections: the NAS power supply goes to an appropriate battery-backed outlet, while the outage signal travels over a supported data connection. A USB charging socket does not establish USB data support.
In Synology DSM 7, UPS support offers USB, SNMP and Synology UPS-server configurations. Choose the mode documented for your actual setup. For another NAS platform, use that platform’s instructions rather than copying DSM settings.
For direct USB, connect the UPS data cable to the NAS USB port. Synology’s compatibility notes say USB hubs are unsupported. The CP1500PFCLCD’s optional RMCARD205 supplies its SNMP/HTTP network interface; that card is not included in the base UPS offer. A Synology network UPS server uses a different path: USB to the server NAS, then local-network notices to configured clients.
Understand the storage system’s safe state
Synology describes DSM 7 Standby Mode as stopping services and unmounting volumes. It allows a configured delay or a low-battery trigger, with low battery taking precedence. Check recovery settings separately; do not equate every safe-state mode with an immediate full power-off.
Document the intended trigger and the time your system needs to reach its supported safe state. Runtime must cover that sequence at the connected load. A display estimate or a battery self-test does not prove that the NAS will complete it.
Include the dependencies that carry the signal
A network-based notification path needs its connecting equipment to remain powered. Synology’s network UPS instructions specifically call for the connecting switch or hub to share the UPS supply. Map the actual route before relying on remote notification.
Include storage enclosures and other required equipment in your power plan. Keep both the watt and VA load within the UPS limits and use its published runtime chart at the intended load. Do not treat an adapter rating as a measured runtime input.
Worked example: budget for the safe-state sequence
Arithmetic with assumed loads: a 60 W NAS, a 20 W router and a 20 W switch total 100 W across three powered devices. This is a hypothetical power plan, not measured DS923+ consumption. CyberPower’s CP1500PFCLCD runtime table estimates 66 minutes at 100 W with fully charged, new batteries under normal conditions; age, charge and environment can change that estimate.
Suppose you choose a 5-minute outage delay and assume 3 more minutes to reach the documented safe state: the planned sequence needs 8 minutes. Those times are illustrative, not Synology recommendations or measured shutdown times. Verify your actual trigger and completion time using manufacturer procedures, including the low-battery override. Check the VA limit, adapter spacing and the powered notification path separately.
Fill in the UPS sizing worksheet to record your load, runtime evidence and compatibility questions. You can print a blank or completed copy.
Verify behavior without inventing a test
Before relying on the arrangement, preserve current backups and follow the exact UPS and NAS manufacturers’ verification procedures. Resolve any conflicting instructions with the manufacturers; do not improvise a utility-loss test by pulling the UPS wall plug.
Record whether the NAS recognizes the UPS, which trigger is configured, how storage reaches its safe state and how recovery is expected to work. HoldBackup has not performed this test. Battery backup does not replace a separate data backup.
Choose the guide for your equipment
- Line-interactive vs standby UPSCompare voltage regulation, then check the waveform your equipment needs.
- UPS for a router and modemKeep the basic internet connection powered; check the provider’s equipment too.
- UPS for a desktop computerSize one PC and its display, then check operating-system shutdown.
- 1500VA UPS for a home officePlan the combined desk load and decide which devices must shut down together.
- UPS for a home network closetMap switches, access points and the complete powered network path.
Sources
Recorded AI check: Sep 26, 2026. The sources below may include later additions. AI checks compare factual numbers and checkable claims with web sources; they do not verify every statement.
- Synology DS923+ UPS list: CyberPower model and recommendation status
- Synology DSM 7: UPS support and Standby Mode
- CyberPower CP1500PFCLCD: specifications, software and runtime
- Schneider Electric: watt and VA ratings for UPS sizing
Best UPS battery backup for a home and APC vs CyberPower compare units from the makers' numbers. Every guide in this class is in UPS battery backup.
How this guide was made
- Drafted and checked with AI. An AI model wrote the draft from the guide's topic. A second AI pass looked for factual numbers to check against web sources. This does not verify every statement. A draft that fails the check is held for review.
- Fact-checked by the HoldBackup editorial team. On , a person on the HoldBackup editorial team reviewed this guide against its sources. That is a review of the writing, not a test of any unit.
- General guidance only. No prices, rankings, or test results, because we have none to back them. Check any number against the maker's own spec sheet.
- No lab tests, and we say so. HoldBackup has not run any unit named here.
- The store link is not a pick for this guide. It goes to a unit in this product class that this guide does not review. Check it against the list above before you buy.
- Labelled store links. A store button goes straight to Amazon with HoldBackup's affiliate tag. HoldBackup counts the click. A live button carries a "paid link" label, and the disclosure sits above the first one on every guide.
Questions
Does any UPS with USB support automatic NAS shutdown?
No. Confirm that it is a data connection, that the exact pairing is supported, and that the NAS has the correct UPS mode and trigger configured.
Is the CP1500PFCLCD verified with my NAS?
Synology lists CP1500PFCLCD for DS923+ as Vendor Recommended, not Tested by Synology. HoldBackup has not tested the pairing. Check the current entry for your exact NAS, firmware and connection, and verify its documented safe-state behavior. The DS923+ entry does not specify UPS power-off support.
Does DSM Standby Mode mean the NAS immediately powers off?
Not necessarily. Synology describes it as stopping services and unmounting volumes. Review the separate UPS power-off and recovery settings for your supported configuration.
Where does the price button go?
Straight to Amazon. Amazon sets the price and availability, and both can change.
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