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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How can I protect my PC? [closed]
So a few days ago there was a power outage in my area. I shutdown my PC which is connected to my UPS (https://www.cyberpower.com/in/en/product/sku/bu1000e). I left room and when I came back like half ...
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Using two TP4056 modules to charge two cells in series
Here's an attempt to get use two modules of charges to charge and protect each of its own batteries connected in series.
Adding back-to-back P-mosfets and a shottky diode converts the whole system ...
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UPS cord has back-flowing current in it. What to do? [closed]
If the UPS is switched on and it's unplugged from the wall socket, then there's some current in the plug pins as per my neon line tester. It's a three pin plug. The earth pin has no current but both ...
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How to calculate or estimate power inverter's peak power
What should be fine to consider as peak power output of an inverter when a motor starts for example?
given that:
Capacity (Rated Power): 935VA / 12 V
Solar UPS Overload:110%
Solar UPS Short Circuit ...
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Ender 3 with a battery powered backup
I wish to develop a battery powered power supply to provide uninterrupted power supply for long duration 3D prints in an environment where mains power is unreliable.
A regular ups power supply would ...
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Can a generator with rated ouput 2.5kW handle 2 PCs rated 600W and 500W connected to two UPS rated 3000VA/1500W and 2000VA/1200W [closed]
I'm having issues with different answers from ChatGPT and Bard. I'm not an expert so I would appreciate an expert opinion.
I have a PC rated 600W connected to a UPS rated 2000VA/1200W with a power ...
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Input/output USB power flow control depending on battery powered or wired
This seems like a very basic problem but I cannot really find a solution or come up with one on my own. The setup is simple (also picture for clarity):
A circuit that takes 5V input
Put a UPS with ...
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How to maintain inverter voltage without change in accordance with load variation, what is the best method, how to implement it in program?
A PIC microcontroler based sinewave inverter, the feedback using an operational amplifier, feed to the ADC, as per the ADC value the PWM duty cycle will change.
I am looking for a best method to ...
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Does power factor fluctuation affect my UPS?
I have noticed that my UPS is showing a power factor of 0.7 during the day and 0.55 at night. I did some online research and found that this is caused by load imbalance, and a low power factor means ...
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Convert Jackery (solar generator) to use as UPS without losing battery quality
I have bought this Jackery device and I want to use it as UPS. I know that if I would connect it in between of socket and load it will act as UPS, but that will degrade the battery quickly. My ...
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Can’t read code on blown capacitor
I have a blown capacitor with damaged code (maybe 102?45)it’s from a charging circuit board from an
8zed-2000S-12v-UPS inverter/charger/UPS.240v-15amp charger the markings on the board are NTC1. I can’...
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More UPS batteries, more fun (and power)
I got some semi-old UPS batteries in stock and hooked them up to my Eaton S3 700VA to test it out, and it seems to work pretty well: charge, discharge and feedback from the UPS to the UPS-software (...
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How does this half bridge inverter charger charge the battery?
I just can't understand how this inverter charger actually charges the battery. The charging circuit uses two SCRs on the mains side of the transformer. The same transformer is also used to step up ...
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Earth Leakage Breaker Trips .. Where is the problem?
I am trying to install a UPS in my home .. diagram of the circuit attached. UPS is in first floor. Both floors have separate main circuit breakers .. Ground floor has Earth leakage breaker while First ...
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What is the alternative for a capacitive power supply? [closed]
I am trying to make a UPS, which will need to pass safety regulations. I need to detect:
When the mains AC voltage is present
When the mains AC voltage is under/over voltage
I thought of using a ...
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Is this a functional and reliable Reverse polarity protection?
Guys, I am trying here to design a UPS controlling board, I designed this circuit and it was to some extent functional and it draws approximately 16mA - 20mA (I don't want to use the traditional one ...
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Adding communication to a dumb 12V in-line UPS
Edit: By "battery" I mean DC-DC UPS, I did this to avoid any confusion with an AC-AC UPS that would sit before the 12V adapter, but it seems to have caused more confusion. This DC-DC UPS is ...
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Help identify components
This board is from a UPS. I was trying to remove the defective SA1 switch and accidentally broke one of the pins of the “J63” capacitor (its reference is C22 but it’s not showing).
The board part ...
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DIY Double Conversion Power Conditioner
I'm trying to build an AC-DC-AC converter similar to how an online double conversion UPS works, but I have a few concerns as I have only basic electronics knowledge and no real qualifications.
I live ...
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USB-PD DRP controller with Custom UPS board
I am trying to accomplish, combining a USB 3.2 Type-A port with a USB Type-C jack, which supports USB-PD DRP (Dual-Role-Power), like in a laptop, as described in this post. The part of USB-PD with USB ...
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Lead-acid battery seems to be gaining capacity through use; why is this?
I am testing an alternative battery cartridge for an APC 3000 VA UPS. It's an OEM cartridge, but with the OEM batteries removed and replaced with Duracell 12 V, 5 Ah SLA batteries by a third party.
I ...
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RTC UPS power cycle on low battery
My RTC UPS switches on and off the whole time when the battery is low.
I think it could be with the voltage monitor circuit as with the led indicator on the ups it shows the ups's battery voltage is ...
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Is it possible to pair MPPT/PWM charger with a computer UPS? Would it prolong the UPS battery's lifespan?
I've an old UPS for my computer which draws 50 W on average and less than 150 W at full load. With the the built-in battery I only have about 10 minutes of backup time.
I am thinking about getting a ...
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How to implement battery back-up?
My goal is to build a circuit that uses a battery (B) as backup when the current from a 5 VDC power supply goes away. When we have power there then we supply current to the load (R) and charge the ...
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Will a 12 V DC/DC converter be damaged if it gets an external voltage (like 13.6 V) on its output?
I'm using a DC/DC converter (has an incoming voltage of 8-40 V, and an output voltage of 12 V) to connect it to a UPS instead of a lead-acid battery and power up some devices from a large capacity 4S ...
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Using li-ion instead of lead-acid in UPS (72 V-DC)?
I've got a UPS that charges its batteries with 84 V 1.5 A (6S1P SLAs). I want to replace the batteries with li-ion 20S2P. I'll use an external charger to charge them in cases of prolonged power-...
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Diagnosing a transformer
I am diagnosing a 22 year old UPS (APC 1400RM) problem, the big transformer (430-7140A) is getting very hot yet the UPS works and self test reports fine. I suspect something is going to fail soon and ...
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Can I use a device of 100-240 V~, 50/60 Hz on a 720 W/1200 VA inverter? [closed]
I am using an inverter back-up power solution device with 720 W/1200 VA output capacity.
I have connected a sound speaker with the below specs:
Input voltage: 100-240 V~, 50/60 Hz
Input current: 200 - ...
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Can I power a router, some HDDs and a Raspberry Pi4 from the same power supply?
I want to build a kind of NAS. See the plan in the picture below.
Is it ok to power all the devices from the same power supply? A friend of mine warned me that it might not work because of the so-...
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Can I keep a 12 V lead-acid battery plugged in continuously?
I want to use the battery as a backup to a security camera that requires 9 VDC input. Can I keep the charger (12 V, 1 A or 14 V, 1.7 A) continuously plugged in to the battery and supply 9 V to the ...
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MOSFET delay while switching
I was making a UPS for my router. My battery voltage is 8 V and V1 is the output from the power adapter, which is also 8 V. When the power goes off, the MOSFET should switch to the battery output, ...
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How can I decrease the relay release time when the current on relay coil is reduced slowly?
I'm trying to make a backup power supply for a home WiFi router (12V, 0.5A) and observe that the relay release time for a QYT73 relay is around 1 second. That is enough for the router to reboot, which ...
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UPS doesn't provide any power on battery - Battery broken? [closed]
I have a CyberPower CyberPower BR850ELCD-AU UPS.
It is a couple of years old and when I tested it a few days ago, I noticed that on battery, i.e. unplugged from power it does not provide any power to ...
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Uninterruptible Power Supply work from battery duration
I am going to buy an UPS, and on website that sells is written that model contains battery with capacity 9 Ampere-hours, 12V DC output voltage and UPS resulting output voltage is 220 AC.
On the page ...
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Online UPS: Saving Power with solar panels [closed]
We have a 300kW online UPS for a data center.
An AC/DC converter converts mains to DC, which is used to charge 2 x 50 12V batteries (50 connected in series each) and at the same time feed the DC/AC ...
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Is hysteresis needed for this non-inverting comparator?
I’m trying to figure out if the following comparator circuit (TL331) would be reliable in the following application, or whether I would need to add anything, like hysteresis.
To explain the ...
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Classifying levels of dust and dirt inside power electronics
I have a fleet (100+) of 100 kVA and above uninterruptible power supplies across the UK. They are designed to be super reliable. I work as the "reliability engineer" so local engineers ...
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Is it possible to use a Li-ion power tool battery while on a charger?
My plan would be to use a 20 V (x2) power tool battery with a step-down converter to power a 12 V radio.
I would also like to be able to power the radio from the wall through the battery charger, ...
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UPS for battery with minimum quiescent current
I am powering a PIR sensor which has minimum 3.4V of VCC and 70µA supply current with parallel Li-ion batteries and I want to switch on a boost converter when battery voltage goes below 3.5V. But the ...
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UPS vs portable power station capacity ratings
I have been looking to buy a dedicated 220V AC offline UPS or portable power station with an offline UPS functionality. What surprised me is that, whereas both are very similar devices, is that ...
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DIY 12V computer UPS
I am considering making a 12V UPS for an ATX computer. I would like to know if my concept is sound, (at least halfway so :) )
It's insane that commercial UPS rectify+step-down mains to charge a 12V/...
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How can I power Raspberry Pi Zero / 3B in forest where I don't have enough sun?
I'm making an authonomous robot (like Phoenix probe but very simple and cheap and made for Earth, no moving parts, just sensors). It controlled by Raspberry Pi and will live in forest shadowed by ...
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Can I use MOSFETs as diodes in a battery backup circuit? [duplicate]
I'm trying to design a UPS circuit and I came across this:
(source: idyl.io)
It's a great idea, but I don't like the voltage drop due to the diodes.
Can I use this reverse voltage protection circuit ...
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Live input to neutral out capacitor purpose in UPS
My UPS has a flat capacitor from live input to neutral output. Can I remove this? It works without it anyway.
Q. What is the purpose?
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My UPS inverter is making treble noise
My home UPS is making noise mainly 19.5 kHz as shown in image while charging. It’s 7 years old now.
Model is Sukam Falcon 800
Q. How to solve this issue?
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Can this Raspberry Pi UPS circuit work?
I created following UPS circuit to shutdown my Raspberry Pi 3A+ properly:
I would really appreciate if somebody can review my circuit. I know it's a little bit hard to read, but I'm sorry. I'm a ...
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How to solve application with power spike one time per 24 hour
We have a building where many similar systems run heaters and valves off a 400VAC, 3 phase, 63 ampere supply (45 kW maximum.)
Internal control software in each system turn the heaters and valves on ...
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Can a voltage stabilizer with an offline UPS give the same performance as an online-UPS? [closed]
I have a 5.5 kVA offline UPS backing up a Bewoulf cluster. It works fine during a complete loss of grid power, but when the grid power flickers the cluster shuts down.
Assuming that this is because of ...
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How to prevent self-charging in parallel UPS?
I'm trying to design an UPS for Raspberry Pi that only connects to +5V and GND pin.
PMIC1 is a battery charger connected to a 5V boost. source
U1 is a voltage supervisor that serves as UVLO (PMIC1 ...
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Understanding UPS runtime without Ah rating
Situation: I want to use a cell phone booster only, whose little power supply says 5 V 1 A and use a UPS just for that only in case of power outage.
With the ~$100 ...
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