APC Back-UPS BE650G2-UK vs Eaton 3S Gen2 UPS 3S550B

Researched, not hands-on tested.How we review ›

all judged against UPS units at a similar price

The Eaton 3S Gen2 UPS 3S550B scores 5.6/10 overall, ahead of the APC Back-UPS BE650G2-UK at 5.3/10.

The APC Back-UPS BE650G2-UK leads on UK outlets and build.

The Eaton 3S Gen2 UPS 3S550B leads on NAS and server integration.

They score the same on topology and waveform, capacity and runtime and battery.

APC Back-UPS BE650G2-UK

5.3/10verdict: good, not the best

This is a compact standby UPS for a home office or small homelab with a NAS, router and switch. It suits buyers who want UK sockets, a user-replaceable battery and a USB link for a clean shutdown. It is not aimed at long outages or heavy loads.

Typically about £99.99 in the UK when we researched itCheck price at Amazon UK

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Eaton 3S Gen2 UPS 3S550B

5.6/10verdict: good, not the best

The Eaton 3S Gen2 3S550B is a small standby UPS for a home desk or a compact homelab. It suits someone protecting a NAS, router and switch who wants USB-triggered shutdown and a user-replaceable battery. It doesn't suit anyone who needs a confirmed waveform, a published runtime or network management.

Typically about £83.99 in the UK when we researched itCheck price at Amazon UK

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Scores, criterion by criterion

Criterion	Weight	APC Back-UPS BE650G2-UK	Eaton 3S Gen2 UPS 3S550B
Topology and waveform	25%	4/10	4/10
NAS and server integration	25%	5/10	7/10
Capacity	20%	6/10	6/10
Runtime and battery	15%	5/10	5/10
UK outlets and build	15%	7/10	6/10
Overall		5.3/10	5.6/10

Specifications

Spec	APC Back-UPS BE650G2-UK	Eaton 3S Gen2 UPS 3S550B
Capacity (VA / W)	650 VA / 400 W	550 VA / 330 W
Topology	Standby (offline), per distributor and retailer pages; not stated on APC pages	Offline/Standby
Outlets	8 total: 6 battery backup and surge protection, 2 surge protection only; BS 1363 (UK)	6 UK outlets: 3 with battery backup and surge protection, 3 surge-only
USB / network management	USB Type A port; no network card listed	USB port (HID-compliant), Eaton UPS Companion software, auto shutdown function; no Ethernet or network card
Battery	Sealed lead-acid, user-replaceable; RBC quantity 1	12 V / 5 Ah sealed VRLA, one battery, user replaceable

Strengths and weaknesses

APC Back-UPS BE650G2-UK

+ Eight BS 1363 outlets, six with battery backup
+ User-replaceable, hot-swap battery with 2-year warranty
+ Surge protection includes DSL line protection
− Only 2.6 minutes at full load
− Standby topology, no network card or SmartSlot
− Owner reports battery failing without a front-panel warning

Skip it if:

Buyers who need long runtime for power-hungry kit
Anyone who wants network monitoring through a management card or SmartSlot
Buyers who want a line-interactive or online UPS

Read the full APC Back-UPS BE650G2-UK review ›

Eaton 3S Gen2 UPS 3S550B

+ USB port is HID-compliant, with automatic shutdown support
+ Battery is a single user-replaceable sealed unit
+ Six UK outlets, three of them with battery backup
− Half-load runtime isn't published by the manufacturer
− No Ethernet port or network card

Skip it if:

Buyers who need a confirmed pure sine wave output
Anyone needing network-card monitoring for several servers
Users who need a published runtime figure before buying

Read the full Eaton 3S Gen2 UPS 3S550B review ›

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