Written 22 Aug 2026. Specs from the maker pages linked below. Prices from those stores. I haven't used these.
Old 24 V passive bricks will not power a modern house AP like a U7 Lite
Leftover 24-volt Ubiquiti bricks can kill a modern PoE port. Skip them. 48 V passive is not the same brick either.
Modern closet APs want 48 V 802.3af/at. Leftover 24 V airMAX / old UniFi injectors are the classic brick-the-port story. Omada EAP613 / EAP653 accept 802.3af or 802.3at and 48 V passive (version-dependent). That is 48 V passive, not 24 V. A 24 V airMAX injector is still the wrong brick.
The converter for this job is INS-3AF-I-G: 802.3af in (48 V) → 24 V passive out, 24 V / 0.5 A max. UI store $20. Use it only to feed legacy 24 V UniFi / airMAX from a modern af/at switch. It does not let a 24 V injector feed a modern af AP. Older UniFi AC-Lite / AC-LR 24 V units are out of scope for new-buy posts. U6 Lite is delisted. Don't hunt used 24 V APs.
What to buy
| Thing | Voltage / standard | Street, 22 Aug 2026 | Use |
|---|---|---|---|
| INS-3AF-I-G Instant Indoor PoE Converter | 802.3af in → 24 V passive out. 24 V / 0.5 A max. | UI $20. B&H 1327765-REG. Central Computer $19.95. | Old 24 V radio on a new af/at switch. Never reversed. |
| U7 Lite | 44–57 V / 42.5–57 V 802.3af only | $99 UI | Does not take 24 V. review. |
| Omada EAP613 / EAP653 | 802.3af or at and 48 V passive | ~$80 | 48 V passive ≠ 24 V. 613, 613 vs 653. |
| Cudy AP3000 | 802.3at/af + 48–57 V passive + 12 V DC | Amazon $69.90 | 48–57 V passive. Still not 24 V. Cudy. |
If you are powering two new APs, buy an af/at injector or a small fanless switch. Don't raid the airMAX junk drawer. Injector math: one injector vs a 4-port switch. First-apartment brick: cheap PoE for two APs.
Skip
Skip any listing that just says “passive PoE” without a voltage. Skip using INS-3AF-I-G backwards. Skip buying used 24 V UniFi APs so you have a reason to own the converter.
Sources
UI INS-3AF-I-G. B&H 1327765-REG. UI Instant 802.3af converter datasheet. Omada EAP613.