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Questions tagged [ups]

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.

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40 views

Give me suggestion on single UPS for Raspberry Pi and WiFi dongle [closed]

I want to design a UPS for RaspberryPi+ WiFi dongle which work on UPS when power fails. I want to design this UPS with lead acid battery because lithium battery has an explosion issue. Give me some ...
1
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1answer
64 views

APC Smart UPS - 2700uF 40V Capacitors

Please excuse the possibly simple question but this is all a bit new to me. I have an APC Smart UPS 1000 which has a very large/tall 2700uF 40V capacitor on the battery (24V) connector. Not knowing ...
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1answer
57 views

Calculate VA of device 100-240v

Firstly I apologise for any mistakes this is deifnitely not my field of expertise. I also apologise if this is not the right place for this question. I have been doing some reading regarding sizing a ...
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1answer
45 views

Variable output from Power Bank (24W = 12v * 2A and 5.4W = 9v * 0.6A)

I started with trying to find 2 UPS for 2 of my routers with the following input specifications: 12v 2A 9v 0.6A I realised that buying 2 power banks will be economical than buying 2 UPS for the AC ...
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0answers
40 views

“lithium for buffered usage in UPS”, or floating-charge lithium accumulator

For lead acid there are typically two paradigms of charging (or use-scenarios). First one is deep cycles, when you exaust 40-60% of capacity (not less than 12.4V), then charge it to 14.4 with ...
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2answers
54 views

Sealed lead-acid battery UPS indoor?

I bought a BX700UI APC UPS for my linux arm server setup (40 watts) to protect it from power cut. - I have the server in the bedroom is it dangerous to have such an Ups in a small bedroom? - Thinking ...
0
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2answers
76 views

The output of a boost converter doesn't stay at 5 V

Let me start by apologizing for my english in advance :) I'm trying to build an UPS for my raspberry Pi (even though I have basically zero experience in electronics). When the power cuts out, I want ...
0
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1answer
62 views

(inverter repairs) Does reverse polarity can kill power MOSFETs in UPS inverters? [closed]

I had an old computer UPS (almost 7 years) and I modified it to use external battery (a 12 Volt motorcycle battery) since the old 12 Volt battery is completely dead and no replacement is available for ...
3
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1answer
78 views

Integrated 5V uninterruptible power supply (UPS) with a lithium cell?

I'm trying to figure out the best way to implement a UPS for an embedded system that runs from a 5V supply. Essentially the system has a 48v to 5v, 1.2A output DCDC converter that powers my system. ...
0
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2answers
62 views

Cap maximum wall outlet voltage

I live in a rural area. A problem occured when my UPS could not run my computer simply because of voltage fluctuations. I have tried many stabilizers but its too rapid that it would make a tick and ...
3
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1answer
84 views

5v power switcher: Uninterruptable power source

I know there are a few other questions similar to mine, but after looking through the answers, it does not seem like it's what I need. I've also looked at the Arduino Due/Uno circuitry, and they aren'...
2
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1answer
99 views

5-10 second backup for wifi router during power cut

In India power cut is often. And most houses are installed with Inver-battery, for backup till the power comes back. But since all inverters don't behave as ups, there occour a little gap between the ...
1
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1answer
88 views

How to add an UPS beeper volume controller so that I can make it sound quieter when it beeps?

I've an EATON 5E850iUSBDIN 850VA/480W UPS. This UPS makes a very loud beep sound both when it's first plugged into the mains(short beep) and when it's first turned on from the button(3x longer beep)...
0
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1answer
50 views

How to protect equipment from voltage anomalies

My refrigerator makes some short anomalies in electric network in my apartment whenever it starts/stops its compressor. I'm not sure if it's a brief frequency change or voltage drop. I can notice this ...
1
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1answer
175 views

Can I replace rechargable batteries with (super)capacitors?

I need a very small UPS just to give an embedded device time to shut down when power is lost. There are a variety of solutions that use LiPo batteries to provide extended runtime; they typically take ...
0
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2answers
47 views

Uninterrupted power switch for 240V

I need to switch supply power from one source to a different one without losing power. I am designing a control system for a customer to run an induction heater. They want to run the system off a ...
1
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3answers
73 views

Operating a fan on UPS

A short, useless intro to the question, feel free to skip it: I had a power outage in my home yesterday. Power outages aren't what they used to be - Back in the day, it rendered me completely unable ...
0
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1answer
157 views

Two 5V Raspberry Pi UPS Idea

I need a cheap, reliable and easy to build UPS for my raspberry pi server. The UPS must maintain power for a maximum of 1 hour. Based on what I found on the internet,I came with two solution. (see ...
0
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1answer
71 views

Lead Acid battery switching regulator to keep constant output

I am trying to use this ups design(below image)(max 500mA) but I want to use switching regulator instead of linear regulator to keep regulated Vout as constant possible even when battery drop below ...
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1answer
99 views

12/24VDC to 240VDC Circuit For a UPS

I need to build a circuit to step-up 12vdc or 24vdc to 240vdc and have a current rating of at least 50A. I got this really expensive UPS from someone but it takes a 240v battery pack which I don't ...
1
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1answer
52 views

UPS for 1.1kW system [closed]

We have 3 motors each 0.37kW, they are now running on mains power, sometimes mains power cutoffs/fails, in that case we want the motors keep running. The motors are controlled by a PLC which do not ...
0
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1answer
121 views

Mini UPS schematic question

I found the following schematic for a rudimentary mini UPS: (Original source website) and in the description on the original website (link above) it says: D2 → Prevents backfeeding of 5v wall ...
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0answers
19 views

Can hard wired ups be wired to IEC60309 plug?

So I've seen some pretty good deal on 6000va ups. The thing is, those ups are required to be hardwire into the circuit. But I may want to move them around maybe even once every few months. And I don'...
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4answers
515 views

5s backup by 1F 5.5V Super Capacitor

Can I have about 4 to 5 seconds backup by 1F 5.5V Super Capacitor? Power supply output voltage: 5v 600mA I need 5v 0.5A for my system. I want to use it as ups for only 4 to 5 seconds so I wasn't ...
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0answers
261 views

How can I design a 12V DC UPS circuit using NMOS?

I have an NMOS with me so I tried to design this 12 V DC UPS circuit after looking at another similar PMOS circuit, but when I open the dc switch, the output is 18kV!! What is the problem with this ...
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1answer
133 views

5 seconds power supply backup for 12V 0.5A router

My country has a problem with the mains electricity supply, which cuts off and comes back straight away. My router restarts every time that happens. What I like to know is: What would be the most ...
0
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1answer
26 views

Is it possible for an intermittent load to draw too much current from a charger that is also connected to a SLA battery?

Planning on this setup as a 12V supply and backup: Load connected to 12V 100Ah SLA Battery connected to a charger (Residential Gateway UPS). Continuous load will be minimal (<0.5A), with an ...
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2answers
223 views

Replace DPDT relay with Mosfet?

Currently I have this UPS power setup for my Router with the help of a DPDT relay so that the router works when mains power supply fails. The working principle of my project is real simple. Two ...
2
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2answers
132 views

UPS causing GFCI tester not to work

Here's an odd one. I have a GFCI-protected circuit with a Uninterruptible Power Supply on it. I've found that when I test the outlets on the circuit with a GFCI outlet tester the tester does not ...
0
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1answer
62 views

UPS specifications [closed]

In a UPS specication, in Input data section, it says current consumption is 18.6A maximum? What is the meaning of this? I am using a DC power supply before this in my circuit. Is it that the size of (...
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0answers
53 views

Android Phone Voltage Drop with DIY DC UPS

i'm currently developing some kind of an IoT with an android smartphone. it's going to be mounted fix on the wall with some enclosure. and i'm using phone's microUSB port for an USB OTG so i power the ...
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2answers
442 views

Unstable 11-13.8 volts to 12v regulator. DC-DC buck or Zener diode, how to do it better?

I have 12v power source Mean well PSC-60A with UPS function and acid buttery. In datasheet says, that output can be regulated from 12-15V - but it's not true, because tested results for output was: ...
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2answers
254 views

Super capacitor in UPS system instand of battery

I got an idea to use super capacitors in UPS system like battery replacemant. I have UPS what give me 220V/2000W what use 3 batteries 12V/7,2A. That UPS power whole my office (lights, computers, ...
0
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1answer
291 views

P/N mosfet and Ideal Diode, how does this circuit works

This is what I found in http://durdoor.com/bin/ideal-diode when I search up some Li battery charger and UPS (Uninterruptible Power Supply) circuit. I realize Q3+Q4 makes an ideal diode (for battery ...
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0answers
87 views

read serial output of a dc ups

I have unbranded ups that output 12volt,9 volts and, PoE 24 volts I wanted to get some info from the ups to a raspberry pi such as how much charge is left and weather it is charging or not, I opened ...
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1answer
49 views

UPS battery advice

I have a APC UPS with a 9 Ah battery. Would it be ok to replace it with an 18 Ah battery? I realize that some modifications would be needed since it won't fit in the case.
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1answer
300 views

Can one battery bank be connected to two static UPS devices?

To make a redundant static uninterruptible power supply (UPS) configuration such as pictured below, I have seen warnings in UPS manuals that each UPS is to be connected to its own battery bank. But ...
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1answer
377 views

Why does my UPS click and beep continuously? [closed]

here where I live there's a lot of voltage fluctuations ( it can't be helped. ) so I bought a ups ovislink cobalt 1000+ ( 1000va) ( line interactive it has an AVR ) ok it works perfectly except it's ...
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2answers
311 views

Can grid-tie inverters charge UPS batteries if connected to the UPS output?

If you have a UPS powering some load in an off-grid situation, and you have a solar panel with a grid-tie microinverter, is it possible to connect the grid-tie inverter to the UPS output, such that ...
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2answers
179 views

Y.S. Tech Fan 4 wires, but which is which?

I've a Y.S. Tech fan with 4 non-standard colored wires connected in a UPS, and I want to replace that fan with a bigger standard 4pin fan doing a "UPS case mod". Motivations aside. Here I want to ...
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2answers
280 views

5V UPS circuit with NiMH joule thief backup

I'm trying to design a UPS circuit for microcontroller backup. Require 3.7-5V, and less than 50mA for 10 seconds every 15 min. Power cuts in my area are never longer than 3hours, and occur rarely. I'...
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2answers
156 views

Unknown smd device from ST replacement possible? [closed]

first time here I would like to ask what is the blown up device on the picture. I think its somekind of diode. I searched the ST site, but I didnt find anything with these markings. The board is from ...
8
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3answers
495 views

5V ups circuit oscillating?

I'm trying to design a 5V UPS. Power to load should switch if line voltage falls below about 4V. Battery voltage may be from 3.8 to 5V. I'm simulating in LTSpiceIV. I'll be using mosfets to supply ...
0
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1answer
79 views

How to UPS-protect this “dual source” setup? [closed]

I'm analyzing how to best protect a setup comprised of a NAS/Router/Wimax from power surges. A very simple diagram is this: When I write "dual source" (term which I just invented) I mean that the ...
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0answers
239 views

Bypass battery of UPS

I have DC-UPS http://www.mercury-pc.com/product-detail.php?link=p-ups&subtitle=UPS&productid=1255 I want to make this ups bypass battery(by using a switch), the switch connect and disconnect ...
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0answers
106 views

Blown varistor after connecting UPS?

I have a pellet burning stove and the manufacturer provides for two options for battery backups. One is an inverter and deep cycle battery that can run the device for a few hours, the other is a UPS ...
1
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1answer
102 views

Is my laptop charger is working as harmonic filter and absorbing harmonics?

I have a square wave backup inverter (UPS). Whenever the power goes out, UPS turns on but all the fans run with noise and humming sound. I know it is because of square wave and harmonics. But when I ...
0
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1answer
138 views

Can UPS with small internal battery used with large external battery ? what are the issues?

I have APC BX1100C-IN 1100VA 230V Back UPS UPS , there is internal battery in it. Its gives 15 minutes backup in case of power failure. I am planning to increase the backup time from ...
0
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1answer
378 views

Need advice on UPS circuit with variable voltage input

I want to make my own UPS circuit and I extended the one I found here so that I can connect 5V to up to 28V to it. I've tested the circuit with some parts that I had laying around (not exactly the ...
0
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1answer
393 views

Li-ion Step up to 5V 8A

I am trying to design a DC to DC UPS using a Li-ion 5000 mAh battery where my load is between 5 V/4 A - 7 A. My system requires keep running after an outage about 20 mins. The load is a RPI3 with ...