PoE switch question

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jbrook3708

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#280382 11-Dec-2020 13:45

Have got a 802.3af compliant switch and considering buying an IP camera with 802.3at requirements.

Switch supports PoE Power up to 15.4W for each PoE port

IP camera requires a max of 14W.

Will my switch power the IP Camera sufficiently considering my switch is not 802.3at compliant?

chevrolux

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#2620110 11-Dec-2020 13:53

Really just depends on the camera. I would hazard a guess and say your cable run probably isn't that long, and if the camera is just a bog standard "home user" level camera, its unlikely to pull anywhere near it's full power requirement.

The one time I've seen an actual problem with at vs. af was with a big-boy PTZ ($4k+ camera), on a long-ish cable run, with a consumer level af switch. As soon as you went to pan, the camera would just shut down. Fixed easily with an 802.3at injector.

sbiddle

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#2620155 11-Dec-2020 15:07

If the IP camera says 802.3at in the spec it quite possibly does need an 802.at switch - it's not so much just about the POE watts rating because the device and switch need to negotiate the class rating. If the camera wants class 4 and the switch can't supply that then it probably just won't power up.

There are a growing number of cameras that require 802.at these days.

richms

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#2620205 11-Dec-2020 16:28

Just try it and see, My cheapie 802.3af switch will poewrup and operate 802.3at gear fine. Even reads the wattage up to at least 17 ok.

Richard rich.ms

jbrook3708

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#2621187 14-Dec-2020 09:31

Thanks all,

Since discovered my el-cheapo NVR supports PoE 802.3.at so I might be off the hook anyway.

jbrook3708

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#2625020 21-Dec-2020 16:03

For those interested the switch was able to power the IP camera sufficiently.

Device models are:

TP-Link TL-SG1005P

Hikvision DS-2CD7A26G0/P-IZ(H)S

sbiddle

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#2625065 21-Dec-2020 18:11

You're pretty lucky it worked. The camera says it's a class 4 device and that switch isn't class 4. Certainly some of the Dahua stuff that needs class 4 simply won't power up at all.