Powering five 24V (4 wire) devices on the WS-6-MINI

[harold]

I've have received my WS-6-MINIs and have been playing with one of them. I really like it so far. We've had good luck with a 12 and 8 port switch that we have as well. I can't wait for the 8 and 12 port DC models to be born...

Here is my question. During the 'void the warranty' testing that I do, I plugged an old MT RB411 into port #2 and powered it on using the only 24 volt option for port #2, 24VH. The port starts flashing indicating 24VH but then goes solid green. The GUI still shows 24VH but no smoke from the RB411.... Next I try an RB433, RB911, and finally a NetMetal. They all seem to work fine. Does this switch check for 4-wire devices and switch to 24V even in the 24VH setting? Sorry if this is answered somewhere else, I just couldn't find any references anywhere. Once again, great switches!

[sirhc]

24VH and 48VH only blink until they get a link then go solid, when it goes solid it is still VH. This was a request made a long time ago my Mike Calivin as he hated blinking red lights as it always made him feel there was an error so we agreed that a blinking red light is only needed before a link occurs to warn those people that go against all warnings by us NOT to plug in LIVE POE ports especially 48VH ports so we held that blinking theme into 24VH to differentiate at a glace what the POE option is set to.

Port 2 of the WS-6-MINI is ONLY capable of 24VH and 48VH using all 4 pairs. Now does it hurt to power most legacy POE devices that only uses 2 pairs you might ask and the answer is NO 99.9% of the time as the Ethernet transformer protects the PHY. This is also why plugging "most" non POE devices into a live passive POE port does not hurt the device.

The reason Ethernet ports are magnetically coupled to isolate the actual PHY of one device from another device is to protect the devices that may be up to 100 meters apart and on totally different electrical service panels and thus have 2 different Earth ground which would fry the PHYs because of the ground potential difference WHICH IS EXACTLY WHY I TELL PEOPLE THEY MUST BOND TOWER GROUNDS TO ELECTRICAL SERVICE GROUNDS OR YOU WILL LOSE ETHERNET PORTS IN RADIOS. Now actually all that gets lost under most circumstances is the Ethernet Transformer which protects the PHYs via magnetically coupling.

As you notice in this example below of a typical 10/100 passive POE connection using pair 3 & 4 to carry DC power are physically connected but pair 1 & 2 caring data are magnetically coupled between the PHY's (no physical connection) so a ground potential difference between the devices will not fry the PHY's.

HEREis a good explanation

CLICK IMAGE BELOW TO SEE FULL SIZE

transformer.jpg (53.32 KiB) Viewed 4896 times

[harold]

OK, got it. I have not used any 48VH devices on these switches yet and didn't realize that is how the indicators worked.

Yes, I learned many years ago the benefits of common grounding after the third time I rebuilt an Astron35 regulator board at a Ham repeater site. I was setting there thinking what the heck... when suddenly it came to me. It went a lot like this:

Thanks for the quick reply.