UPS Battery backup

[Electrotech]

Thinking about getting a UPS battery backup to run my Jebao RW-8 powerhead in the event of power outage. We lost power here last night for about 3 hours and I was right in the middle of unpacking my little 200W inverter and running the car to power the pump when the power came back on.

I've been researching UPS backups today and there seem to be a lot of variables. The powerhead draws around 23W max according to the manufacturers spec, but I'm now sure if that's AC or DC I'm assuming AC for following.

The UPS I have been looking at is cyberpower CP825LCD which is 825VA 450W backup. I wont need true sine wave as this is a DC pump and has a DC power supply.

I'm trying to figure out how long this would run my pump. It says it has a 8.5Ah battery. So according to BatteryStuff Tools | AC to DC Amperage Calclator Through An Inverter it will draw 2.32 Amps DC off the battery. If battery is 8.5Ah ad powerhead draws 2.32A I should get 3.6 hours of run time.

Does this sound right?

I may modify it also and add a second battery in parallel for double capacity. So 17Ah for 7.2 hours of run time.

 

[Electrotech]

Oh, I was also thinking about plugging my apex into it and getting a second UPS for my router and modem in the event of power failure have the apex e-mail me.

 

[gtbarsi]

Oh, I was also thinking about plugging my apex into it and getting a second UPS for my router and modem in the event of power failure have the apex e-mail me.

Generally speaking what you want to look at is the AC/DC adapter that you plug in, and use it along with the sizing tools the UPS manufacturer has to determine the best model.

In my experiences one big UPS is much better than multiple smaller ones. In addition there are regular UPS units, and then there are extended run units. The extended run units have more batteries and can maintain a load for a much longer period of time. I personally use an APC 750XL for my computer gear and network and I can keep working for about two hours when the power goes out. It has my quad-core VM server on it with three monitors, VOIP phone, network switch, and the base for the home phone, and some other items like external USB disk drive. By comparison the 750 regular would only get me about 20 minutes....

In the end the UPS manufacturer sizing tools are there to do the math for you since they are able to translate the batteries in a unit to the amount of time it can power a given load. There are a lot of factors not the least of which is the power the UPS uses to maintain itself while it provides power. There are electronics and cooling fans involved, not to mention the efficiency of covering DC to AC is not 100%.

 

[Electrotech]

I would rather have 1 large one for the powerhead/apex and the router/modem but they are or different floors and opposite ends of the house. So 2 smaller ones will have to do and I only need the router/modem one on long enough to send 1 email from the apex after power failure.

 

[Velodog2]

I have one designed specially for router/modems that only outputs 12 volts. No point converting from a battery up to 120 only to convert back down to 12 again. It lasts for about a day.

 

[cope413]

Your numbers are off...

Not sure about the RW8, but my Jebao WP-25 runs off 24v. It uses 8-20w, depending on the mode/setting.

watts = volts x amps

So then, it draws between .33a and .83a of current.

So an 8ah battery could power it for between 9.5 - 24hours.

Ignore anything except the Watt Hour rating of the UPS.

You'll find that most pieces of equipment in the hobby use around 1a - with the exception of heaters - because more current = more heat, and we obviously want to control our heat input.

(4) 12v 12ah Yuasa NP12-12 batteries would probably give you enough juice to power your essential equipment for 3-5 days.

 

[Electrotech]

Your numbers are off...

Not sure about the RW8, but my Jebao WP-25 runs off 24v. It uses 8-20w, depending on the mode/setting.

watts = volts x amps

So then, it draws between .33a and .83a of current.

So an 8ah battery could power it for between 9.5 - 24hours.

Ignore anything except the Watt Hour rating of the UPS.

You'll find that most pieces of equipment in the hobby use around 1a - with the exception of heaters - because more current = more heat, and we obviously want to control our heat input.

(4) 12v 12ah Yuasa NP12-12 batteries would probably give you enough juice to power your essential equipment for 3-5 days.

The RW-8 uses around the same 9-23W depending on mode and setting. I was figuring 25W for inefficiency in the AC-DC converter. I was assuming it meant 25W of AC power at 120V equals .21A

The inverter/battery calculator i linked said a .21A draw on 120V converting back to 12V DC for the battery factoring in inverter inefficiency would be a 2.32A DC on the battery

 

[Electrotech]

Kind of as a comparison I just borrowed my neighbors cyber power cp600lcd and it showed a 80 minute run time when disconnected from AC. The battery is 9-12 months old so might be due for a change. It also said that the load was 0%.

 

[menglish]

Not sure this will help you, hopefully. I cam across this video a few weeks ago as i too am rethinking my backup system. I currently have a deep cycle marine battery (27DC from Costco rated at 750 AH), and a 1100W power inverter that i have for my 90 G tank. I know i can run my Mag drive 7 pump for at least 10 hrs.
Anyway, check out this video out from AmericanReef channel
https://www.youtube.com/watch?v=QObiv5ulBFg
The Neptune Apex Sucks --- Power - YouTube
good luck

 

[Electrotech]

very interesting video. Thanks, seems like the apex is a hog. I may get end up sticking with the smaller ups and apex setup for notification and then I can come home if out and plug up a inverter from the car or a generator if I can find a nice Honda inverter/generator used.

 

[Electrotech]

If anyone else is looking I cam across this today. heck of a deal for a larger UPS with pure sine wave for running AC pumps.

APC Smart-UPS 1000 USB (SUA1000) - APC UPS System | RefurbUPS.com