UPS for server room

[Adcadet]

Hey Gang,
My family and I successfully made the move to Wisconsin. We're about done re-configuring our basement, which will include a "server room". So far it has it's own 20 amp circuit and the cable modem/router/switches/smart things hub/garage door controller, and perhaps other stuff will go into this wall mount rack enclosure (link: http://www.amazon.com/gp/product/B009B1I1C8?psc=1&redirect=true&ref_=oh_aui_detailpage_o00_s01). For now I have two servers (FreeNAS) that run Plex and act as backup servers.

The Plex server and backup servers can go down but I'd like to keep certain key pieces of equipment on a UPS to keep some basic functionality in the event of a power loss. I'm not sure I need an online UPS and am wondering if I can get by with a line active UPS (a quick modem/router/smart things reboot wouldn't be the end of the world). I'd like to keep the network running for at least an hour, and preferably a day or two.

Any thoughts about this approach? Any suggestions for equipment to look into?

 

[Howell]

An online UPS is safer but not strictly necessary. How often do you expect events to occur?

The calculation fire size is pretty straightforward. What is the wattage draw for all the devices you will have plugged in and how long do you need them to stay up. If you need some to stay up longer than others you could split duties across a couple UPSs.

 

[Bozo]

If you want to run for days, I'd suggest an emergency generator setup. You could also power other devices in the house like the heat. It gets very cold in Wisconsin.

 

[Stereodude]

Several days = generator, or DIY racks of batteries connected to a UPS.

 

[Adcadet]

I'm hoping the draw would be fairly minimal for just a modem, router, switch, and two home automation thingies. I'll have to do the math.

Frequency of events is probably minimal - few times per year.

 

[Handruin]

I was also looking into a UPS for my basement and there may be some additional info you can leverage in this thread. I still haven't decided what to buy for myself but had been considering using the refurb option that was suggested in that thread.

 

[ddrueding]

I was performing some tests on a very high capacity UPS for low loads (couple hundred watts) over a long period of time. Specifically an APC SMX2200RMLV2U with 5x APC SMX48RMBP2U battery pack additions. The power consumption of the unit itself (control circuitry, fan, etc) was much higher than my load, and cut the total run time to less than half of what I'd predicted.

I'm designing the second iteration, it will include a small solar array and be more cost effective than huge numbers of batteries.

 

[Buck]

If you can (have $ and the natural gas feed), a natural gas generator.

 

[Adcadet]

We do have natural gas. Will look into a generator at some point. But for now I just want to power a few key items that I hope draw relatively little power.

 

[Mercutio]

On a mildly related topic, Amazon and Newegg were both offering APC BGE70 "home network" UPSes for $20 last week. They're meant to run your router, cable modem and maybe a phone or something for around 4 hours. I'd never heard of that product line prior, but it's a solid idea and possibly a starting point for your plans.

 

[Howell]

I was performing some tests on a very high capacity UPS for low loads (couple hundred watts) over a long period of time. Specifically an APC SMX2200RMLV2U with 5x APC SMX48RMBP2U battery pack additions. The power consumption of the unit itself (control circuitry, fan, etc) was much higher than my load, and cut the total run time to less than half of what I'd predicted.

I'm designing the second iteration, it will include a small solar array and be more cost effective than huge numbers of batteries.

Somebody else specced twin 1500s for my big switches. When I ran through the calculations I found I needed twin 3000s for the system and twin 2200s for the poe.

 

[ddrueding]

One of my upcoming designs is built around everything on the system being 48v PoE and being driven directly by a 48v battery bank that is charged directly by a 48v solar charge controller fed by panels. This should eliminate most of the efficiency losses and allow the system to scale much more economically.

 

[blakerwry]

If you can (have $ and the natural gas feed), a natural gas generator.

I agree. Another option would be solar. As Dave mentioned, most battery based units are not designed for prolonged runtime (more than a few hours) and perform poorly at this application. This page from APC does, however, list some solutions for 24+ hr runtimes.

 

[Howell]

One of my upcoming designs is built around everything on the system being 48v PoE and being driven directly by a 48v battery bank that is charged directly by a 48v solar charge controller fed by panels. This should eliminate most of the efficiency losses and allow the system to scale much more economically.

Interesting. I can't envision how that would work. Where do you get 48v input power injectors or 48v input switches. I guess you could splice in custom connectors.

 

[ddrueding]

I can pump 48v into this and power PoE devices.

This switch runs off PoE.

This should let me pull 48v out of the PoE to power non-PoE devices that can take 48v (like IR illuminators)

 

[Pradeep]

I was performing some tests on a very high capacity UPS for low loads (couple hundred watts) over a long period of time. Specifically an APC SMX2200RMLV2U with 5x APC SMX48RMBP2U battery pack additions. The power consumption of the unit itself (control circuitry, fan, etc) was much higher than my load, and cut the total run time to less than half of what I'd predicted.

I'm designing the second iteration, it will include a small solar array and be more cost effective than huge numbers of batteries.

How about a big bank of flooded lead acid batteries and an appropriate charger/inverter? Main downsides would be venting, space and weight. Also would prob want to limit discharge to 50% of potential to extend battery system life.

 

[ddrueding]

How about a big bank of flooded lead acid batteries and an appropriate charger/inverter? Main downsides would be venting, space and weight. Also would prob want to limit discharge to 50% of potential to extend battery system life.

This is what I'm looking at for my new system, only skipping the inverter step if possible for efficiency reasons. We have access to lots of cheap porta-potties mounted to pallet skids. I'll probably gut one, install some shelves, stick the batteries on the shelves, and bolt the charge controller to the door. That should be sheltered enough, well vented, easy to transport and yet not likely to be stolen.