2 WS-6-MINI on 24vdc via barrel?

[agidi]

Hello, requesting opinions from more experienced users.

Due to our location, getting hardware and stable energy is complicated.

We recently had to replace UPSs TS5 and TS8, we considered the EdgePoint S16 and the WS-6-Mini and the mini won. It has all we need nothing we dont.

We had two of them plugged into a decent UPS, and powered via a 48v POE from some UBNT equipment. We are experiencing issues with the power company, they drop a line and we get 66v until after several hours 8-20hrs it comes back to 130vac.

66v is too low for the UPS. so it kicks in. Last time we ran out of battery juice.

So we started building our own UPSs for the EdgePoint R6 which runs on 24vdc.
We use... a

24vac 50VA wall transformer that feeds and Altronix power supply and charger, set at 12vdc
See its specs https://ftp3.syscom.mx/usuarios/fotos/p ... 20SMP3.pdf
This board charges a deep cycle 12vdc battery .
The DC output of the altronix board goes to a DC-DC Voltage converter that takes 12vdc and turns it into 24vdc
See its specs https://www.amazon.com/gp/product/B00JU ... UTF8&psc=1

This last item powers the R6 at 24vdc

Now i need to know from the Netonix Gurus if I can power 2 mini-6 via their barrel plug from this output, and load them with Rockets (no airfiber), or how much watts can i load them off. It would run off 24vdc.

I altronix makes this board in 3 and 5 amps.
But i see the mini6 will only take 48v 2.5amps?

The benefit of using this setup is that when AC voltage drops to 66vac , the wall transformer still does 24vac and the altronix will only kick in in battery mode when the power is less or the voltage drops more.


please advice thanks

[sirhc]

Your asking if you can power a WS-6-MINI via 24V????

[agidi]

yes and how many watts of APs can i load on them.

[sirhc]

yes and how many watts of APs can i load on them.

You can not power the WS-6-MINI with 24V

I am confused why you thought you could power the WS-6-MINI with 24V ?

The switch "might" power up with 24V but it will not provide any POE.

CLICK IMAGES BELOW TO VIEW FULL SIZE

[agidi]

Got it, so we could upgrade to a DC-DC 12v to 48v converter regulator.

and if my math is not too rusty, i can demand up to 120watts from a 2.5amp 48v barrel plug right?

I just want to double check with you. I cant loose a switch. thanks

[Julian]

the 6-mini is rated at 100w. The switch itself will use 5-8w internally, depending on packet load, ambient temps, etc.

The reason we power with 4-pair 48vh versus 2-pair 48v has to do with the ampacity of cat5 cable: using 2 pairs only allows 1.25A or 60w, you draw more than that and the wire starts heating up, so we designed it to take power from 4 pairs since it can draw up to 100w.

If you'd like, make me a block diagram of what you're envisioning, and I'd be happy to take a look. As long as you're not pushing more than say 75w constant draw @ 24V out the front, should be no issue, but do post that drawing, please.

Thanks,

Julian

[sirhc]

Plus when the WS-6-MINI is getting power from POE IN on port 1, if you're only using 2 pair (what we call 48V) instead of 4 pair (what we call 48VH) you should not feed the switch or use more than 1A total as Ethernet Transformers with a center tap are only rated to 1A per pair.

When using 4 pair POE IN on port 1 you're not putting too much stress on a single pair of the transformer which can now handle up to 1 Amp per pair so the Transformer can pass 1 amp per pair or a total of 2 amps across 2 pair before it is stressed or could be damaged.

You might ask; " but we are using 4 pair".......but 2 pair are for positive and 2 pair for negative so you're still limited to 2 Amps before you could damage the Transformer.

[lligetfa]

The last two posts seem to overlook the OP's desire to power it with the barrel connector, not PoE and the question was about the watts that it supports via barrel connector.

[Julian]

thought i answered that with the 100w thing, guess that got kind of lost in excess information.

powered via barrel adapter: switch can draw 100w safely. 48v 2.25A supply will be sufficient. you will have a ~92w power budget for powered devices. Drawing in excess of that budget will have an adverse effect on system stability, but should not damage anything irreparably, caveat emptor.

is hopefully succinct.

[sirhc]

The last two posts seem to overlook the OP's desire to power it with the barrel connector, not PoE and the question was about the watts that it supports via barrel connector.

He can feed the switch with more amps than it needs.

You could feed the switch 100 Amps with the barrel connector or POE IN on port 1 so long as you are not really using that much power.

Think if it this way, you have a 20A breaker for a bedroom in a house. Now you only plug in a single lamp in that room with a 25 watt light bulb. The bulb and lamp do explode or catch fire even though 20 Amps is WAY MORE than the lamp needs or uses.

So yes you can feed the WS-6-MINI via the barrel connector as you want and even via POE in on Port 1.

However if the switch is getting power in via POE in on port 1 the POE controller chip is limited to 100 watts so if you use more than 100 watts you are using more than you should and bad things could happen.

If providing access to more power/amps in on the barrel connector once again this does not matter how many amps the source is it matters how many amps you are using and pulling through the board. Then it comes down to how many amps the connector is rated at which is more that 2.5A and then how many amps or watts the PCB can handle.

So the WS-6-MINI is capable of being configured to provide the following max on each port:
Port 1: NON POE PORT - ONLY FOR POE IN
Port 2: 48VH 1.5A
Port 3: 48V .75A
Port 4: 48V .75A
Port 5: 48V .75A
Port 6: 48V .75A

So "if" the switch is configured for MAX use you are setting up the switch to transfer 4.5A in POE. Will the switch really be delivering this amount? I highly doubt it.

On average you might see the following real world usage:
Port 2: 48VH powering an AF24 1A/50 watts
Port 3: 24V powering an airMAX radio .25A/6 watts (average)
Port 4: 24V powering an airMAX radio .25A/6 watts (average)
Port 5: 24V powering an airMAX radio .25A/6 watts (average)
Port 6: 24V powering an airMAX radio .25A/6 watts (average)

So a fully loaded WS-6 might be pushing an average of 74 watts

Now if a device being powered fails and shorts out or a cable shorts then the power/load shoots up but the polyfuse heats up and opens up.

Will you damage the switch in the process if a short occurs.......sometimes yes, sometimes no.

So it does not matter if the DC source feeding the switch is 2.5 or even 100 Amps.

If you hook a tiny 0.1A 12V light bulb to a car battery it does not explode because it does not matter how many amps the battery is capable of delivering the light bulb will only use what it needs. Where the problem with having sooo many Amps at your disposal is when something goes wrong like a dead short but in the case of the switch there are Polyfuses which will heat up and open up breaking the circuit just like a circuit breaker in your house.