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hEx S: 802.3at in, passive out?

Fri Jan 29, 2021 3:51 am

I'm going to be getting a hEx S and powering it with a 802.3at ethernet injector. And, hEx S' PoE out port will power a CRS305 with two 10Gbase-T modules. Can the hEx S convert the 802.3at to the passive power that it outputs in the out port? The CRS can take in any type of power, but it seems a little surprising to me if the tiny little hEx can convert the 802.3at to passive power to send out.
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Re: hEx S: 802.3at in, passive out?

Fri Jan 29, 2021 11:59 am

There's no converting done. HEX S gets power by 802.3at. When HEX s has power, POE OUT gets the same voltage.
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Re: hEx S: 802.3at in, passive out?

Fri Jan 29, 2021 6:19 pm

To clarify a bit: hEX S can have two power sources connected: PoE in (which can be anything between 12V and 57V) or DC jack (with same voltage range). PoE in can be 802.3af/at as well. If both power sources have different voltages (e.g. 802.3af/at at 48V and provided 24V DC adapter), then the source with higher voltage is used.
As @quackyo already wrote: passive PoE out devices (such as hEX S) provide input voltage on output port. In case when dual power sources are provided (the case explained in previous paragraph), PoE out offers same voltage as used by device itself. Not that CRS305 would mind that as it can take same PoE in voltage range as hEX S.
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Re: hEx S: 802.3at in, passive out?

Mon Feb 01, 2021 7:47 am

@mkx and @quackyo provided an answer about the conversion on the device.
In this case you may use RBGPOE-CON-HP.
This device lets you use any 48V PoE source (including Passive PoE, Telecom PoE, 802.3af and 802.3at) to power RouterBOARD devices.
Simply plug any 48V PoE powered ethernet cable into one port, and any 8-30V capable RouterBOARD device into the other. This device is capable to provide high power output - up to 24W (up to 1A at 24V).

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