When you're shopping for critical power, the used market offers real bargains, but only if you compare the right details. The Eaton 5P 1550VA and the APC Smart-UPS X 1500VA are two rackmount units that look similar at first glance, but they diverge in important ways. This head-to-head breaks down what you need to know to pick the one that matches your setup.
Quick Verdict
The Eaton 5P1550GR is listed at $174.99 and the APC SMX1500RM2UNC at $199.99, a 13% price spread. That's the most concrete difference to start with. The rest of your decision depends on the specific needs of your rack.
Comparison Table
| Feature | Eaton 5P1550GR | APC SMX1500RM2UNC |
|---|---|---|
| Listed price | $174.99 | $199.99 |
| Price bar | ||
| VA / Watts | 1550VA / 1100W | 1500VA / 1200W |
| Form factor | 1U rackmount | 2U rackmount / tower |
| Input voltage | 200-240V AC | 120V AC |
| Signature feature | Pure sine wave | Network Management Card (NMC) |
| Battery included | Yes (1x lead-acid) | No |
| Condition | Used, fair physical condition | Used, Grade B tested working |
Where Each Product Wins
The Eaton 5P1550GR takes the lead for pure sine wave output, which is gentler on sensitive electronics like servers and medical gear. Its 1U rack height also frees up vertical space, a real advantage in a dense rack. The APC SMX1500RM2UNC, on the other hand, offers a higher 1200W output (vs. 1100W) and a built-in Network Management Card, so you can monitor and manage the unit over the network. If you need that remote visibility and have the floor or rack space for a 2U chassis, the APC's extra power and management are worth the higher price. If conserving rack space is the priority, the Eaton's slim profile wins. The APC's ability to also run as a tower gives it placement flexibility, but that comes at the cost of more physical space.
Product Notes
Eaton 5P 1550VA 1100W 1U Rackmount UPS
The Eaton 5P1550GR includes its lead-acid battery, which is a real convenience for a used UPS. With many used units, the battery is missing or spent, so having one in the box reduces the initial hassle. The physical condition is fair, with light scratching and scuffing on the chassis, and the functional check was limited to confirming the unit powers on. If you're willing to accept cosmetic wear and a unit that hasn't been fully exercised, this is a straightforward way to get a rackmount UPS without a separate battery purchase. For buyers who prefer a complete package, the included battery is a tangible advantage. Just keep in mind that a used unit's battery may need to be replaced sooner than a new one.
APC SMX1500RM2UNC Smart-UPS X 1500VA 1200W 120V Rackmount Tower 2U NMC
The APC SMX1500RM2UNC arrives as a Grade B working unit, with the display and battery-charging function confirmed, so the core electronics appear healthy. The major catch is that no internal or replacement battery is included, so you'll have to add one before the UPS can actually provide backup power. Factor in the cost of a new battery when weighing the price. If you're comfortable sourcing a battery separately, this used unit is a functional platform to build on. The fact that the battery-charging circuit is confirmed working is a positive signal, since a non-functioning charger would be a bigger problem than a missing battery.
Final Choice
If your rack runs on 200-240V input, the Eaton 5P1550GR is the unit to get. If your equipment uses 120V, the APC SMX1500RM2UNC is the one that fits. Let your main voltage be the tiebreaker. For most buyers, the input voltage of your facility is the single most reliable guide between these two units.
