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Title: Cisco SG300-10 Switch for Yamaha QL5 & Dante
Post by: TomBoisseau on February 02, 2017, 05:12:54 pm
I'm about to purchase my first Cisco SG300-10 switch for use with a Yamaha QL1 and QL5.  The problem is that there seems to be MANY choices within this same product line (see the link below and the click "View All").

The features I want are:
10 ports
PoE

But, even then there appears to be a few different versions.  Could someone please assist me in choosing?

Thanks,
Tom


http://www.cisco.com/c/en/us/support/switches/small-business-300-series-managed-switches/tsd-products-support-series-home.html

Title: Re: Cisco SG300-10 Switch for Yamaha QL5 & Dante
Post by: Nathan Grater on February 02, 2017, 07:25:33 pm
They are great switches. This is my understanding of of the differences:

SG300-10 - no POE

SG300-10P has 8 POE ports but is limited to 15W/port and total of 64watts

SG300-10MP has 8 POE ports but is limited to 15W/port and total of 124watts

SG300-10MPP has 8 POE ports but is limited to 30W/port and total of 124watts
Title: Re: Cisco SG300-10 Switch for Yamaha QL5 & Dante
Post by: TomBoisseau on February 02, 2017, 08:00:54 pm
They are great switches. This is my understanding of of the differences:

SG300-10 - no POE

SG300-10P has 8 POE ports but is limited to 15W/port and total of 64watts

SG300-10MP has 8 POE ports but is limited to 15W/port and total of 124watts

SG300-10MPP has 8 POE ports but is limited to 30W/port and total of 124watts


Ah! Okay.  That helps a lot.

Thanks so much.

I'm inclined to purchase the model with the highest wattage for PoE with 10 ports.  I suspect while I might not need it now, in the future I'll probably glad I spent the few extra dollars.  I'm leaning towards the SG300-10MPP which is 124W (PoE+ supported).  What do you think?  Any comments?


I see there is a comparison chart with specs here:

http://www.cisco.com/c/en/us/products/collateral/switches/small-business-smart-switches/data_sheet_c78-610061.html

Title: Re: Cisco SG300-10 Switch for Yamaha QL5 & Dante
Post by: Ade Stuart on February 03, 2017, 08:54:44 pm
Personally, I find the 10 port Cisco SG300 with POE a pain to package. You can rack mount them but there is a large external power supply.
Title: Re: Cisco SG300-10 Switch for Yamaha QL5 & Dante
Post by: TomBoisseau on February 04, 2017, 08:46:19 am
Personally, I find the 10 port Cisco SG300 with POE a pain to package. You can rack mount them but there is a large external power supply.

You make a good point, and I am aware that many prefer to get the rack mount version with 20 ports or more.  For my application, this unit will never be in a rack and, I just prefer to have a smaller footprint.

Thanks,
Tom

Title: Re: Cisco SG300-10 Switch for Yamaha QL5 & Dante
Post by: TomBoisseau on February 04, 2017, 09:52:38 am
Are there any concerns plugging non PoE devices into the PoE ports of the SG300-10MPP?  For instance a console, Rio box, or another non PoE switch?

Title: Re: Cisco SG300-10 Switch for Yamaha QL5 & Dante
Post by: Ade Stuart on February 04, 2017, 10:36:45 am
Are there any concerns plugging non PoE devices into the PoE ports of the SG300-10MPP?  For instance a console, Rio box, or another non PoE switch?

I haven't seen any problems connecting QLs, Rios, WAP and other switches. I've never felt the need to check but I suspect POE is configurable by port on the SG300 and I believe POE is only supplied after handshaking.
Title: Re: Cisco SG300-10 Switch for Yamaha QL5 & Dante
Post by: Mac Kerr on February 04, 2017, 10:42:03 am
I believe POE is only supplied after handshaking.

I wonder how handshaking works when one of the devices hasn't been powered up yet...

Mac
Title: Re: Cisco SG300-10 Switch for Yamaha QL5 & Dante
Post by: Philip Roberts on February 04, 2017, 12:03:13 pm
I wonder how handshaking works when one of the devices hasn't been powered up yet...

Mac
A Powered Device has a 25k resistor across the powered pair(s) when powered off. Higher or lower resistance means that power isn't supplied.

High power modes are negotiated after an initial low power startup.

Philip
Title: Re: Cisco SG300-10 Switch for Yamaha QL5 & Dante
Post by: Ade Stuart on February 04, 2017, 12:16:38 pm
I wonder how handshaking works when one of the devices hasn't been powered up yet...

Mac

An active device can interrogate a passive device before the interrogated device is powered. This is a protocol that is used in electric vehicle charging for example but now we are off topic... 
Title: Re: Cisco SG300-10 Switch for Yamaha QL5 & Dante
Post by: Scott Holtzman on February 05, 2017, 08:17:56 am
An active device can interrogate a passive device before the interrogated device is powered. This is a protocol that is used in electric vehicle charging for example but now we are off topic...


802.3af is the specification.  It's and IETF spec.  Being able to plug a non-powered device in without damage is a requirement.  http://www.rhyshaden.com/eth_poe.htm



Title: Re: Cisco SG300-10 Switch for Yamaha QL5 & Dante
Post by: TomBoisseau on February 06, 2017, 08:39:22 pm
Well...

I just picked up a SG300-10MPP.  You guys are right!  That's a BIG, nasty, power supply.  I understand now why so many were recommending the rack mount 20/24 port version with an internal power supply!  That probably makes sense.

Tom