Can you run 4 x 15V POE cameras from a 48V NVR?

[JoshThomson]

My 15V NVR blew up and the online store said I could replace it with a 48V and the cams would with with a POE switch.

What sort of specs should I look for?

I tried using an old gigabit switch but I couldn’t get it to work. Maybe I didn’t set it up right. Last time I just plugged the cams into the NVR and it detected them.

I’m a newb so apologies for any rampant stupidity. I went through the great installation docs on the newbs forums but I couldn’t find anything.

Help and thanks for your time!

 

[Will.I.Am]

What exact cameras are you using?
Compliant poe devices will run off apx 48v, but there are "poe" devices that aren't actually "poe" in that they'll run off a standard poe switch or nvr, but only that a proprietary device can deliver power to them over an ethernet cable (this is also known as passive poe)

Active (802.3at or 802.3af) is generally better because the poe is only delivered when the two devices (switch and network device) are both compatible with a poe standard.

Active poe switches can't power passive poe devices because the passive devices can't tell them that they need power, or how much they need.

 

[TonyR]

Are cams or NVR made by Zmodo or Funlux?

If the answer is "yes", their sPOE (simplified POE) is not 8023.af or 802.3at compliant and is about 15 to 19 volt passive.

 

[JoshThomson]

Thanks so much for your replies!

Unfortunately it’s a cheapie from AliExpress and they don’t make the same model anymore so it probably not true POE.

“Techege 4CH 15V PoE NVR 2.0MP 1080 POE Camera”

Would a POE splitter help or should I just bite the bullet and get 4 new 48V cameras?