A UPS is an Uninterruptible Power Supply that provides backup power when the main power source is lost. Questions on repairing commercial ones are generally off topic.

learn more… | top users | synonyms

0
votes
0answers
66 views

Why doesn't this UPS use a high-frequency SMPS inverter?

So I've bought a 350VA off-the-shelf UPS so I can continue learning about how things are done - you know, things they don't teach in the classroom. I get the thing open and I discover what appears to ...
0
votes
2answers
51 views

12v capacitor / UPS system [duplicate]

I am looking to make a capacitor/UPS system for a few different electrical components in my car. I want to power the rear view camera, headrest monitors, and possibly the head unit for about 30 ...
0
votes
1answer
32 views

Need to know battery configuration for a 250 watts inverter [closed]

I have a 12 Volt inverter which have ability to produce 250 W output. I would like to purchase a battery for this. can any one tell me the configuration of battery ? eg: Minimum AH
1
vote
1answer
244 views

50/60Hz inverter output inductor design

Given a SMPS PWM inverter (for example an UPS) supplying voltage/current at 50/60Hz, how do you design an output inductor? I don't mean how you compute its value in uH/mH nor its current rating in A. ...
0
votes
3answers
76 views

Diode rating for a UPS project with extra battery

I am planning to add an additional 12volt deep cycle battery to my APC UPS but I dont want to use the charging circuit built into the UPS. I think that if I throw in a Diode between the external ...
0
votes
1answer
200 views

Backup power for adsl modem

I want to create a circuitry for switching to backup power (small battery) in case of mains power failure for my ADSL modem (to avoid the internet going down in such scenario). This is a basic ...
-1
votes
1answer
55 views

Can I use a UPS to compensate for unsteady line-power? [closed]

One of the outlets in my home provides unsteady power that causes connected electronics to occasionally shut down. If I buy a battery backup device such as this will it be able to compensate for ...
1
vote
1answer
81 views

Humming Sound of UPS vs DSP Inverter

I have a APC 1000VA BR Smart UPS.I have noted that the UPS Produces a Humming Sound when running on Battery Power.But my older a normal 500VA UPS(not from APC) seems to produce far lesser humming.The ...
0
votes
1answer
162 views

Will a PSU with Active PFC Work with Normal UPS

Im getting a Seasonic SII 620 with Active PFC.The problem is that i have a pseudo sine wave ups or just a normal UPS.Will this PSU work with the back up power offered by the UPS?
3
votes
2answers
121 views

Buffering AC supply voltage and detect power loss?

I'm designing a system integrating: an industrial PC with 230V AC input (~300W) various peripherals requiring 24V DC (150W max) In case of external AC power loss, the DC components (2) need to be ...
2
votes
0answers
69 views

Is it possible to charge 3 parallel batteries without sending charge to the UPS?

I have a UPS (uninterruptible power supply) with a 220VAC input designed to be used with 12V batteries. It has a rated capacity of 400 watts and I've placed three 12V car batteries in a parallel ...
2
votes
3answers
375 views

Convert 320VDC to 220VAC or 48VDC voltage using 220VAC (UK) UPS?

I've got access to 12 flexible Solar Panels - 320VDC each Main voltage is 220VAC (here in the UK) and also might buy an electric engine running at 48VDC. Would a 220VAC Uninterruptable Power Supply ...
1
vote
2answers
206 views

Trouble using marine batteries with UPS

First, let me premise this question with the fact that I'm not well versed in electricity. Here's the problem: I am trying to power a UPS with an inverter and two deep-cycle batteries run in ...
3
votes
3answers
190 views

Is there an instrument that can measure the capacity of lead acid batteries

Background I have an electrical scooter with 6 x 12Volt lead acid batteries (72 Volts total), which are now in such a condition that they can barely get me to my work and back. I got a bunch of used ...
1
vote
1answer
330 views

Will a trickle charge lead-acid battery system last?

If I were to implement a simple battery backup system like this to power several WiFi radios in a field situation, how would the battery handle it? Would trickle charging it like that wear it out ...
0
votes
1answer
60 views

Clarification regarding batteries and ups

I am planning to setup a ups with 2 100ah/4h batteries next to my server setup. Is it safe to work to work next to such high load batteries. Are there any health concerns that comes with working ...
-2
votes
1answer
126 views

Why UPS for sensitive SMD development?

My friend suggests me UPS for SMD development. I already have a a surge protector over all devices. He recommended the UPS that transmit all energy through its battery and he recommend to find some ...
1
vote
1answer
918 views

What types of batteries are typically used in UPS (uninterruptible power supply) and why?

They definitely need to be safe for indoor use so they can't vent, they should probably support deep cycling due to the nature of backup power supplies, and I imagine they should have relatively long ...
2
votes
1answer
862 views

Troubleshooting UPS failure

My wife said her office had an old UPS that was being scraped because it wasn't working. I picked it up and plugged it in and nothing happened. No lights, no warnings, nothing. It's a small ...
4
votes
3answers
10k views

Battery Backup: C10 vs C20

I am installing a home UPS system of 1400 VA. The UPS is a 24 volt system and, based on the batteries available on the market for the UPS segment here, will need 2 x 12 volt batteries for it. Based ...
1
vote
1answer
133 views

Does a low-quality UPS affect its battery life?

People say that "local" UPSes (uninterruptable power supplies) reduce the life of their batteries while other, "branded" UPSes are better and do not affect the battery life. I have noticed that a ...
0
votes
1answer
319 views

ups 12v 9ah batteries not charging

I have a 2000VA ups that contains 2 batteries ( 12V 9Ah ). I think that something happened to the batteries, since now they can barely handle an average laptop for about 3 minutes before shutting down ...
6
votes
1answer
228 views

volt-ampere (VA) rating of UPS

I would like to ask about the volt-ampere (VA) rating of UPS. Is there any effect of this value in terms of the time period that the UPS can supply the power?
2
votes
1answer
141 views

Should I look for Aluminum or plastic enclosure for UPS

I am on the process of material selection for the UPS I am prototyping. My plan is to manufacture a product that should finally go to the market. I am relatively new to the manufacturing and I would ...
4
votes
1answer
193 views

Tapping the battery from an UPS to feed low voltage devices

My UPS powers one 120V AC device and a whole bunch of small 'bricks' that end up rectifying things down to 5-12V DC. Instead of using the 'bricks', my idea is to tap the battery directly, and use ...
4
votes
2answers
857 views

Replacing a battery in a UPS

I recently replaced the battery in my APC Back-UPS CS 650 and of course I didn't opt for an original APC battery, but just bought a similar one from the corner electronics shop. Apart from the ...
8
votes
1answer
6k views

Some advice on charging circuit used in simple UPS

I have looked around for some way of having a 5 volt power supply that acts like a UPS. Basically want to use a micro usb connector for +5 have a battery and li-ion or other charging circuit that ...
3
votes
2answers
3k views

Fixing APC UPS buzzing noise

I have an APC UPS and one of the caps - an SIEMENS EPCOS 20uF 150V Capacitor - started making a buzzing noise. This seems to be a AC, non-electrolytic capacitor and most local stores have it priced ...
2
votes
3answers
1k views

UPS connected back to back

this is a theoretical thought. As we know UPS (online ups) . We have outlet from where we connect to other device. And there is a plug point from which we charge. Now my question is what happens if, ...
8
votes
5answers
996 views

Does reactive power cause extra fuel use in a Diesel UPS?

It is a bit of a theoretical thing, of little practical use, but I just want to understand the physics behind it. I am aware that I'm simplifying things quite a bit. In electric power we ...
2
votes
1answer
313 views

What is the current limit on each phase of a 160 kVA three-phase UPS?

I'm a physicist by training, so I think I understand voltage, current, phase and power. However, I lack the knowledge to translate between this and the published ratings on three-phase electrical ...
3
votes
2answers
1k views

Effect of Battery charging with un equal batteries in parallel

I have 24 VDC to 220 VAC Inverter and two 90 Ampere Batteries now I feel that backup is not what I need now I intend to connect these two existing batteries in parallel to give total of 12 volts and ...
2
votes
3answers
237 views

What's wrong with my UPS?

We have a battery & UPS setup on communication systems for an isolated site (wind farm). Last night was the first time the system was put to the test when our grid connection was lost at 11.30 pm, ...
0
votes
4answers
5k views

How long will laptop run from UPS? [closed]

The laptop has input: 18.5V, 2.7A The UPS output is: 220V, 6.82A and also something about 1500AP I have no idea how to work out how long I would be able to run the laptop off the UPS when the UPS is ...
8
votes
2answers
610 views

Can I connect a capacitor in parallels to power supply of a router

In the building where I live, because of older wiring, the mains voltage frequently drops for a fraction of a second and this restarts my wifi router. I am planning to solder a capacitor in parallel ...
5
votes
4answers
601 views

I want to build a DC powered computer, what are the gotchas, where are the parts?

Google builds its servers with a Battery in the box so that they don't need a UPS. I'm wanting to do the same, but I'm wondering what all the gotchas might be for doing this, and where I'll find the ...
5
votes
1answer
387 views

Voltage used to charge a UPS-Inverter and its usage

I'm new to this area and know very little about electrons and how electrical components work. I'm always curious about Inverter/UPS usage. I'm from India and we have a inverter at home. It is ...
10
votes
4answers
880 views

Don Lancaster's Magic Sinewaves

For several years now Don Lancaster is promoting magic sinewaves. They are strings of binary digits (like 420 bits for a full sine cycle) that, when used to drive a digital switch (MOSFET/IGBP), ...
6
votes
5answers
6k views

12V DC UPS for Network Equipment

Many times we want to kept running low power devices like DSL modems, etc. Most of these devices take 12V/9V DC so why to use ordinary UPS which convert AC to DC to AC, lots of conversion lots of ...
3
votes
5answers
269 views

How can computer parts suffer if the computer isn't protected by an UPS?

In datacenters it's common to use Uninterruptible power supply (UPS) to protect the computers. They are used for several reasons, but one is that electronics possibly can suffer from the power grid if ...
4
votes
3answers
486 views

Plugging a UPS into an inverter

First off, I am aware that plugging an UPS into an inverter is a bit redundant. The only situation I can think of it being useful is in a car when you want full amps for cranking over the motor but ...
7
votes
3answers
2k views

DIY 12 Volt UPS

Hi i am trying to make a UPS for a project that requires 12Volts. I'm currently using a replay diode and capacitor. My problem is that when the switchover occurs, the voltage drops from 12Volts to ...