Does HP V1910 JG350a supports passive 24v POE?

[cfede]

Hi,

Anyone knows if this kind of switchs, V1910 JG350a support passive 24V 0.5A POE Access Point?.

I'm reading in the user manual that this switch has an option to "Enable non-standard 802.3af PD function" .

Thanks in advance.

[parnassus]

AFAIK the HP 1910 PoE models support IEEE 802.3af PoE only but you can try to figure out if PSE (the PoE Switch) is able - at least - to recognize the non standard PD (the PoE Device...your AP) through the menu PoE -> PSE Setup, here you can Enable the corresponding Non-Standard PD Compatibility for the listed non standard PD.

IMHO if the PD is an AP - maybe an Ubiquiti UniFi AP? - that uses a non standard PoE (24V DC is a PoE non standard with respect to the standard 48V DC) you should use an external (specific for that type of device) PoE Injector and keep the Switch data port with PoE feature disabled (since there is the external specific PoE Injector that supplies the Power to the AP).

[cfede]

Thanks for your reply.

Yes, I forget to mention, it's an Ubiquiti AP. They came with a PoE adapter as you say but could be more simple to use this HP switch since I already have one of them bought.

Do you think there is a risk to damage the AP or this configuration could work?

[parnassus]

Hard to say...but, even if you want to take the risk, the point is that that AP requires 24 Volt D.C. while the IEEE 802.3af Standard specifies a supply voltage range at PD between 42,5 and 57 Volts...so, at this point, I really don't know if the "Non-Standard PD Compatibility" feature, once enabled, is able to force the PSE to provide half the nominal supply voltage required by a Standard PD (so providing 24 Volts instead of nominal 48 Volts).

If the load (the PD in this case) doesn't change (and so it acts like a pure resistive load) when the PSE doubles the 24V voltage required then applying 48V may damage its (power supply and other) internal components.

More or less, it's like asking if you can power up a laptop with 2x Volt D.C. instead of using its nominal x Volts D.C. power supply voltage...even if the load is able to protect its power supply inlet from the doubled voltage then it will not work because its power supply ratings are not respected at all.

[cfede]

Mmm I think you're right. I don't want to take the risk of damage the APs.

Thanks for your quick answers and info.
Regards,
Fede.