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.

0
votes
1answer
31 views

Raspberry Pi UPS with 18650 + TP4056 + MT3608

I'm trying to make an UPS for my Raspberry Pi 3. Based on https://nomadaselectronicos.wordpress.com/2015/05/22/fuentecargador-con-carga-compartida-load-sharing/ and http://ficara.altervista.org/?...
0
votes
1answer
30 views

use charge discharge pcb as ups [closed]

i have purchased a charge/discharge pbc from ebay and i what to use it as a small ups for a raspberry pi. when the pbc receive 5v from charger, it's charging the batteries and output the same voltage ...
1
vote
0answers
31 views

UPS power supply for both router (12V, 2A) and up board squared (5V, 6A)

I was searching for an UPS (uninterruptible power supply) to power my Up Squared Board (5V, 6A) and my router (12V, 2A). So far I didn't find something suitable but here is my idea: Take a suitable ...
0
votes
1answer
78 views

USB communication keeps disconnecting because of power dip/spike

I've got a question. I've got CNC router that's connected by USB to a desktop computer. We're in an old building, and wiring is not optimal :) I'm not an expert, but I think too many rooms are on the ...
0
votes
1answer
119 views

Help me identify power issues with this PCB

I bought the following UPS module for my Raspberry Pi: Power Pack Pro The module kinda works, when I unplug the power cable, the module instantly switches to battery powered mode without restarting ...
0
votes
2answers
40 views

Power rating of a UPS

I find it odd that manufacturers specify power rating of Uninterruptible Power Supplies (UPS) in VA instead of Watts since VA doesn't tell you how big of a load the UPS can supply. A case in point is ...
0
votes
1answer
56 views

how the battery behaves in this diagram

My question is this. I'm using this ic mppt SM72445 along with a 250 watt solar panel, mppt output configured to 50.4 or 51 volts, 12-cell lithium-ion battery pack and bms, if the load is less than ...
0
votes
2answers
65 views

how a battery behaves in parallel to the charger with a shared load but with a voltage difference

how the battery behaves in this diagram how a battery behaves in parallel to the charger with a shared load but with a voltage difference
1
vote
0answers
31 views

How to get correct response from UPS HID

I have a UPS HID device and I'm trying to use LibUSB to get data from it. The response expected is in the format below: ...
1
vote
0answers
47 views

Raspberry Pi wake-up and battery power circuit

I am working on a Raspberry Pi (3B plus) project that - at times -needs to operate on battery power, and on external power whenever available. The RPI needs to operate only when a dedicated sensor ...
0
votes
0answers
57 views

Problem with driving inductive loads with inverter

Newbie here. I've got this old line interactive type UPS which cannot drive any inductive load. I suspect the issue is with inverter side of the cct as there is no issue when the commercial supply is ...
1
vote
0answers
45 views

TP4056 with DW01, can I use a diode to create an “UPS”? Design review

I'm studying lithium cells and their related mainstream modules. One of the most common -yet wrong- use of the TP4056 module is to use it with the USB 5V input and an active load on the output (at ...
1
vote
1answer
67 views

Why should a UPS fail if the battery fails but the power from the wall outlet is still good?

Sounds to me like a design flaw. Why wouldn't this work? No switching transient and the power supply to the servers (or whatever) fails only if both battery and AC power fail. simulate this circuit ...
2
votes
2answers
107 views

Switch to battery when voltage supply drops certain threshold

I have made this circuit but can't quit make it work. Vext is my main supply from a car (9 - 14V) Vbat is 8 AA batteries (10 - 13V) Vout supplies power to a SMPS As it is now, supply "fades" between ...
0
votes
1answer
68 views

Transformer mains identification

A friend gave me a transformer from an APC UPS that supposedly was capable of \$1300 VA\$ (I have my doubts, but it is very large and I am not going to be using nearly so much power, so OK). He doesn'...
2
votes
2answers
111 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 ...
0
votes
1answer
73 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 ...
0
votes
1answer
73 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 ...
0
votes
0answers
51 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 ...
0
votes
2answers
74 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
votes
2answers
77 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
votes
1answer
139 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
votes
1answer
136 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
votes
2answers
66 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
votes
1answer
127 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
votes
1answer
138 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
vote
1answer
138 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
votes
1answer
79 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
vote
1answer
241 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
votes
2answers
51 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
vote
3answers
172 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
votes
2answers
287 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
votes
1answer
74 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 ...
-2
votes
1answer
115 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
vote
1answer
57 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
votes
1answer
163 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 ...
0
votes
0answers
22 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'...
0
votes
4answers
1k 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 ...
0
votes
0answers
351 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 ...
0
votes
1answer
165 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
votes
1answer
27 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 ...
1
vote
2answers
308 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
votes
2answers
180 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
votes
1answer
65 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 (...
1
vote
2answers
522 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: ...
-2
votes
2answers
437 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, ...
1
vote
1answer
373 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 ...
0
votes
1answer
62 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.
0
votes
1answer
451 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 ...
-1
votes
1answer
539 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 ...