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[SLUG] Re: [chat] Does a PoE switch need direct access to a PoE device?
- To: Simon Males <sime@xxxxxxxxxxx>, slug <slug@xxxxxxxxxxx>
- Subject: [SLUG] Re: [chat] Does a PoE switch need direct access to a PoE device?
- From: Martin Visser <martinvisser99@xxxxxxxxx>
- Date: Mon, 21 Feb 2011 19:11:34 +1100
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Plugging a non-POE switch into a POE switch will work fine - but not
forward on any "power". In simple terms, a POE switch will test,
through various means, whether it is safe to apply the 48V power to
the device that is connecting to it.
So your non-POE switch will not receive any useful power from the POE
switch as it won't meet those prerequisites. It also does not have
capability to pass on "power" to devices down stream. (Obviously all
Ethernet devices need to provide power when they transmit, but only at
signal levels, not able to power devices in the POE sense.)
On 21 February 2011 18:15, Simon Males <sime@xxxxxxxxxxx> wrote:
> Hi Slug chatters
> I'm wearing a network engineers hat as of hat and I'm tempted to
> install a PoE switch as we expand to power PoE supported phones.
> Some phones will have direct access to the PoE switch. But others will
> be connected via other intermediary switches.
> Will an intermediary non PoE switch blow up/block/pass on the power
> from the 'master' PoE switch?
> If the former, I guess daisy chaining PoE switches is relatively safe?
> Simon Males
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