UPSs for network stuff

Power out? How about an inverter connected to your car?
kevm14
Posts: 15200
Joined: Wed Oct 23, 2013 10:28 pm

UPSs for network stuff

Post by kevm14 »

I already have two APC BackUPS 1300RS units. One in my great room which powers my media center (HTPC), TV and probably the network switch. The other is in my bedroom which powers my desktop computer, monitor and network switch. I also have a nightstand lamp connected which is really handy. When the power goes out, I just switch on the lamp and that gets me going to where I can get my flashlight stuff.

Anyway, with this house I had to split my IT stuff up. In the old house, this was all powered from my bedroom UPS. In the new house, in the basement, I have a router, a switch and in the garage I have a FIOS network/media converter box.

So I was looking at what the current UPS offerings are for small loads like these. I found two good ones.

My use case would be to maintain internet during times when the power goes out, but I don't run the generator (i.e. less than an hour). Also, for times that I AM running the generator and I shut it down to refuel (<20 minutes).

http://www.apc.com/shop/us/en/products/ ... RRWidgetID

This one is really cool. $120 MSRP, and Li-Ion. 84VA capacity (small stuff only). It also has a removable power brick that you can take on the go to charge phones and stuff. Neat idea.

In terms of runtime, here are 5 data points for reference:
10W for 145 minutes
15W for 101 minutes
20W for 78 minutes
30W for 54 minutes
50W for 33 minutes

Here is the other Li-Ion option.

http://www.apc.com/shop/us/en/products/ ... RRWidgetID

$300 MSRP. Network capability, which I like, as it would live in my basement with my main network stuff. Would be nice to monitor remotely. Don't think the other one can do that. 500VA capacity.

Run times:
10W for 85 minutes (notice it is significantly less - more electronic overhead in a 500VA device)
15W for 63 minutes (still less)
20W for 51 minutes (still less)
30W for 37 minutes (still less)
50W for 24 minutes (still less!)

Well that I did not expect. For one thing, the first model only does a modified sine which is crappy power but fine for switch mode power supply stuff. The bigger one does quasi-sine. That probably takes more power.

The efficiency graphs also tell the story.

BG500: http://www.apc.com/products/efficiency_ ... Size=large
BGE50: http://www.apc.com/products/efficiency_ ... Size=large

The BG500 does have a better shape to its efficiency curve, meaning it maintains higher efficiency at lower load percentages before falling off. But, the max load of the BGE50 is so low that you'll probably be up in the good part of the efficiency curve. It all comes down to what the expected draw is.

For example, if I end up powering a router, a gigabit switch AND my FIOS network box, lets say that is 35W total.

At 35W draw, the BG500 is 86% efficient. The BGE50 is 91% efficient. In fact, from 50W and down, the small one is more efficient. Which means, I think, as long as I have less than 50W of draw, the small one is ideal. And only $120 MSRP (haven't checked other sources). No network control but I'd be saving $180. And have better performance. On the other hand, APC rates the small one's battery life as 2-4 years. The BG500 is rated at 5-8 years. So...that is something to consider.

The other good news is, Li-Ion is much better suited to deep discharges than the AGM/lead style batteries in conventional UPSs.
kevm14
Posts: 15200
Joined: Wed Oct 23, 2013 10:28 pm

Re: UPSs for network stuff

Post by kevm14 »

Here's a cool thing about the small BGE50:
https://www.amazon.com/APC-M12USWH-Back ... B0146D3XDM

You can buy extra power packs!
$59.35.

Looks like it charges via microUSB so you could use it without the base entirely. I do like the flexibility.

Holy shit. I should have checked this before. The BGE50 is only $50 on Amazon! That comes with a battery. Then you can buy another one for....$60? haha. I guess just buy two of the units then. Weird. But yeah that is cheap as hell.
https://www.amazon.com/APC-Back-UPS-Con ... 05BGBN5A8S

Also the BG500 is only $240.
https://www.amazon.com/APC-BG500-Back-U ... ords=BG500

These prices are not bad.
kevm14
Posts: 15200
Joined: Wed Oct 23, 2013 10:28 pm

Re: UPSs for network stuff

Post by kevm14 »

Wow sounds like a winner.
When unit goes on battery, does the audible alarm continue to beep until AC power is restored?
Answer: Nope. Just one loud beep, and the green light flashes. It's nice, because my other APC battery backups keep beeping until the battery is dead.
You could even put these next to individual lamps or something. So cheap. It would power a standard LED light bulb for almost 2.5 hours.
kevm14
Posts: 15200
Joined: Wed Oct 23, 2013 10:28 pm

Re: UPSs for network stuff

Post by kevm14 »

Power measurements are in.

Verizon FIOS box: 34-35VA. Out of 84VA that is 41% load. That would run for about 78 minutes. Really bad power factor on this box (which is why you need to use VA whenever possible, not watts).

Adding my router and network switch, the total becomes: 53-55VA which rises to about 64% load. That is 50 minutes.

This should be perfect. I would probably start the generator by 50 minutes and if it was a shorter outage, obviously that would work, too. I also shut down to refuel and that is well under 20 minutes. More like 5 minutes. So good there, too. And unlike the lead acid based systems, this charges in only 2.5 hours (8 hours via microUSB in mobile form).

Somehow I am still tempted to order 2 of these even though I only need one. Maybe just to have a spare power brick.
kevm14
Posts: 15200
Joined: Wed Oct 23, 2013 10:28 pm

Re: UPSs for network stuff

Post by kevm14 »

Ordered. One.

It will be here by Wednesday. If I like it, perhaps I'll order another one. It would be nice to have a power brick to charge phones if I am NOT running the generator. In which case I could tether, and charge via the brick. So, still useful in that scenario.

In case anyone is still reading, I should mention that the power brick when separated from the housing only powers things via USB. It needs to be docked to make the AC inverter work.
kevm14
Posts: 15200
Joined: Wed Oct 23, 2013 10:28 pm

Re: UPSs for network stuff

Post by kevm14 »

A review.

https://www.youtube.com/watch?v=VGGsJVdpBN8

He powered a router and cable modem for 2 hours 8 minutes.
bill25
Posts: 2583
Joined: Thu Oct 31, 2013 2:20 pm

Re: UPSs for network stuff

Post by bill25 »

Can I borrow the meter to test the camera consumption?
kevm14
Posts: 15200
Joined: Wed Oct 23, 2013 10:28 pm

Re: UPSs for network stuff

Post by kevm14 »

I brought it in.

I may have made an error on my run time calcs. Let me break it down.

- The 50W/84VA rating is describing the size of the inverter. It has nothing to do with the battery pack size. You can have a tiny inverter with a huge battery, or a huge inverter with a tiny battery, or anything in between. They are not related. The size of the inverter drives how big of a load you can plug into the UPS. 84VA refers to 0.7A @ 120V. 120 * 0.7 = 84VA. The 50W rating is assuming an average power factor of 0.595 which is pretty low but can happen when the load is driven by a shitty modified sine wave (i.e. a square wave). If you have a meter such as a Kill-a-watt that can measure load VA, use that to determine whether the inverter can power the load. I am good because I was in the 53-55VA range, drawing around 0.46A @ 120V.

- The run time is specified as a % of max load, and they have a graph that says max load is 50W @ a 1.00 PF. That is confusing and where I guess I made an error (still not 100% sure). We can do some back of napkin calcs to see if we can determine the right way to rate it. Battery capacity is 41.2 Wh (11.4 Ah * 3.7V cells). If the inverter and battery were 100% efficient, that would drive a 41.2 watt load for 1 hour. Their spec graph says 40 minutes. It is possible that the whole setup is only 66% efficient.

http://www.apc.com/products/runtimegrap ... Size=large
Curve fit to measured runtime data. All measurements taken with new, fully charged batteries, at typical environmental conditions, with no electrical input and balanced resistive load (PF = 1.0) output.
It's pretty clearly stated really. Where I went wrong before, I think, is I should measure volt-amps and compare against the watts for the load. Why? Because the 0-50W load has a 1.00 PF. So I could put my Kill-a-watt in watts, write that down, then put it in power factor mode, write that down, and divide watts by power factor. OR, I could just put it in VA mode directly.

All that said- I got 53-55VA. The graph only goes to 50W. That doesn't mean I am overpowering it but they just don't graph the data. Remember I am still inside the 84VA max capacity. I know, confusing. Anyway, at 50W, the runtime is 33 minutes so let's call it 30. The solution is easy if that is insufficient - I can just buy another one and keep one for the router/switch and the other for the FIOS box. I don't know that I even need more than 33 minutes but maybe...
kevm14
Posts: 15200
Joined: Wed Oct 23, 2013 10:28 pm

Re: UPSs for network stuff

Post by kevm14 »

Finishing the thought, if I had two, the long pole would be the FIOS box. Which would run for 47 minutes. So for another $50 I can have another 17 minutes of uptime. That doesn't sound good unless those are a really key 17 minutes. They might be when you are talking 30 -> 47.
bill25
Posts: 2583
Joined: Thu Oct 31, 2013 2:20 pm

Re: UPSs for network stuff

Post by bill25 »

The numbers are in for 1 camera - .20 PF, 5 Watts, 25 VA.
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