Power Mini by 2 x 24 VDC in series (48 VDC) ??

[Chris@edgarhighspeed.com]

Here I am waiting for my new mini's to come in and I got to thinking that maybe I should look at installing a mini at my tower site. I have been currently redesigning the tower site to run everything off of 24VDC.
this 24VDC is being generated from tycon systems TP-SCPOE-2424.
it is a very small site, 1 Rocket AC Lite (8.5 Watts), 1 Powerbeam 500AC (8.5 Watts), 1 nanostation loco 2.4 (5.5) watts and 1 tycon power TP-DIN (3 Watts) (to keep watch on it all) Thats a total of 25.5 watts @ 24 volts thats 1.06 amps
so here is my question.
the mini can be run from 48 VDC and the TP-SCPOE-2424 has 2 X 24 volt outputs. 1 is 1 amp and 1 is 1.5 amp output. I was thinking about wiring the 2 x 24 volt outputs from the TP-SCPOE-2424 in series to create 48 volts and then powering the mini. Which in turn powers the above mentioned gear.
Does anyone see a problem with this. other than maybe under powered for future expansion (1amp vs 2amps)
system would look like this:
Port 3--->Rocket AC Lite (24V)
A/C input --> meanwell 48 Volt power supply --> TP-SCPOE-2424 --Output 1 (24V) --->Wired in series (48VDC) ---> MINI Port 4--->PowerBeam (24V)
| --Output 2 (24V) --->wires 1234(+), 5678(-) Port 5--->NanoStation loco(24V)
| Port 6--->TP-DIN (24V)
(charges 2x 12 volt batts in series=24 volt)

I know it's probably easier and faster to buy a DC version of the switch or change the charger to a tycoon TP-SCPOE-2448 that outputs 48 volt POE but hey checking out options

Regards

Chris.

[sirhc]

I am not so sure that will work.

Hooking to DC power supplies together in series is not a good idea and does not work like hooking batteries in series.

I think you will fry the power supply.

[highlands]

sirhc is correct, you will indeed at least pop the fuse and at worse destroy the power supply!

If you are not going to make the site a 48 VDC site you only have three choices.

1) purchase the WS-8-250-DC and leave your site at 24VDC

2) purchase a 24 to 48 converter (which the WS-8-250-DC has in it and is ready for service) such as a Meanwell or a Vicor then use a WS-6-MINI

3) change your site to 48 VDC and use the WS-6-MINI

The TP-DIN is a good product an does work well on 48VDC systems also. I would suggest you convert your site to 48 for a second reason. Here is why. the UBNT gear when you ask them or look at the spec sheet does not want more than 26VDC. Why, I never figure that out since soooo much of it is used on solar sites around the world, and I my opinion it is very short sited of UBNT to do this and have been prodding them for almost 10 years on this one subject, only to (as normal) have it fall on deaf ears.

With your AC powered site some of the following does not apply to you, as all you do is float charge your batteries at 28 VDC and you should be fine most all the time.

Yes we all get lucky for a while with this on 24 VDC sites, because when you charge a 24 battery bank you need 28 VDC. That is above the top end for the UBNT gear. Warranty will not cover this and most of the time the added 2 volt the UBNT gear deals with. But when your batteries go low during to a few days of no sun and then you get a great sunny day the solar charger (as it should) goes in to bulk charge mode where the voltage goes up to 30VDC! Well about that time you can say good bye to some of the gear. Does this happen every day.... no. will you lose the gear every time it goes above 28 or so?....no. But it does happen its just a matter of time, as we have seen many a time on our network in the last decade.

John

[sirhc]

If you are not going to make the site a 48 VDC site you only have three choices.

1) purchase the WS-8-250-DC and leave your site at 24VDC

2) purchase a 24 to 48 converter (which the WS-8-250-DC has in it and is ready for service) such as a Meanwell or a Vicor then use a WS-6-MINI

3) change your site to 48 VDC and use the WS-6-MINI

WE ARE NOT MAKING ANY MORE WS-8-250-DC units, we are however making a lot more WS-12-250-DC (we needed to lower our SKU count).

[highlands]

Apologies, I did mean to type in there a WS-12-250-DC I was not fully (mentally) engaged.

[Chris@edgarhighspeed.com]

Thanks for all the help, sounds like going with a WS-12-250-DC is the correct route. Have to wait until it gets spring time here. too cold to be swapping tower components.

[sakita]

If you are not going to make the site a 48 VDC site you only have three choices.

1) purchase the WS-8-250-DC and leave your site at 24VDC

2) purchase a 24 to 48 converter (which the WS-8-250-DC has in it and is ready for service) such as a Meanwell or a Vicor then use a WS-6-MINI

3) change your site to 48 VDC and use the WS-6-MINI

WE ARE NOT MAKING ANY MORE WS-8-250-DC units, we are however making a lot more WS-12-250-DC (we needed to lower our SKU count).

...I now have an orphanage of sorts with 11 of the WS-8-250-DC ...as long as the new firmware continues to work with them.

Doesn't cost much more for the 12-port (14 port) anyway (and being ready for fiber doesn't hurt either)... and hopefully the WS-12-250-DC switches will once again include happy little LEDs by the SFP ports.

[sirhc]

Yes, all our switches use the same firmware so they will continue to acquire updates.
We may put the LEDs back into the WS-12-250-XX units next production run?