Автор: Всем привет. В этой статье рассмотрим как работает схема от перегрузки. Или устройство защиты и отключения питания при перегрузке. Эта схема основана на регуляторе напряжения из базовой серии.
Как устроена защита от перегрузки
Схема предназначена для использования в устройствах, которые работают с постоянным током 9 вольт и максимальным током до 100 мА. Оно не подходит для устройств, требующих более высоких параметров тока. Схема функционирует как стабилизатор напряжения и представляет собой базовую конструкцию серийного типа.
Она включает следующие элементы:
-Tрансформатор с вторичной обмоткой на 12-0-12 Вольт и током 100 мА. Он выполняет две функции: обеспечивает изоляцию от высокого напряжения, а так же снижает напряжение. Центральный отвод вторичной обмотки трансформатора управляет базовым двухтактным выпрямителем, который дополнен фильтрующим конденсатором для улучшения качества выходного сигнала.
При отсутствии нагрузки выходное напряжение может достигать около 18 вольт постоянного тока, которое уменьшится до приблизительно 12 вольт под полной нагрузкой.
-R1 — резистор, который определяет ток в схеме.
-D3 — стабилитрон на 10 вольт, обеспечивающий стабильное выходное напряжение.
-C2 — конденсатор, который используется для поддержания регулируемого выходного напряжения на уровне 10 В.
-Транзисторы VT1, VT2
-Защита по току, резистор R2 и транзистор VT3.
Как работает защита от перегрузки
Таким образом, защита от перегрузки является простым и эффективным решением для батарейных приложений с низкими требованиями к току.
Ток стабилитрона составляет около 8 мА при отсутствии нагрузки и снижается до примерно 3 мА под полной нагрузкой. Это приводит к минимальному рассеянию мощности, создаваемому резистором R1 и стабилитроном D3. Схема включает эмиттерный повторитель в виде пары Дарлингтона, состоящей из транзисторов VT1 и VT2, который служит выходным буферным усилителем с коэффициентом усиления тока около 30 000 при полной мощности и минимальным значением в 10 000.
При таком уровне усиления защита от перегрузки использует 3 мА тока под полной нагрузкой, и при минимальном коэффициенте усиления падение напряжения на усилителе остается практически неизменным, даже если ток нагрузки колеблется. Реальное падение напряжения на выходе усилителя составляет приблизительно 1,3 вольта, что при входном напряжении 10 вольт даёт выходное напряжение около 8,7 вольта. Это близко к 9 вольтам, особенно учитывая, что обычная батарея с напряжением 9 вольт может показывать колебания от 9,5 до 7,5 вольт на протяжении своего использования.
Добавление ограничения тока к защите от перегрузки
Для регуляторов, представленных в схеме, важно предусмотреть защиту от короткого замыкания на выходе. Это необходимо, чтобы устройство обеспечивало хорошее регулирование и поддерживало низкое выходное сопротивление. Поскольку источник питания имеет очень низкое сопротивление, в случае возникновения короткого замыкания может протекать чрезмерно высокий выходной ток, что может привести к повреждению выходного транзистора и других компонентов.
Стандартный предохранитель часто не обеспечивает достаточной защиты, поскольку повреждение может произойти очень быстро, до того как предохранитель успеет сработать и перегореть. В качестве альтернативы, наилучшим решением будет добавление в схему ограничителя тока. Этот элемент может потребовать дополнительных компонентов, но не окажет негативного влияния на работу устройства в нормальных условиях. Тем не менее стоит учесть, что ограничитель тока может привести к быстрому снижению выходного напряжения, если нагрузка начинает потреблять значительно повышенный ток. В результате выходное напряжение может упасть так быстро, что, несмотря на короткое замыкание, доступный ток будет лишь немного превышать установленный предел.
Заключение о работе схемы ограничения тока
В данной схеме ограничения тока используется всего два элемента: резистор R2 и транзистор VT3. Защита от токового перегруза срабатывает очень быстро, что позволяет минимизировать риски короткого замыкания, обеспечивая надежную защиту выходных устройств.
Теперь рассмотрим, как работает эта защита:
Резистор R2 подключен последовательно к выходу, что означает, что напряжение, создаваемое на нем, пропорционально выходному току. Когда потребляемый ток достигает 100 мА, напряжение на резисторе R2 оказывается недостаточным для активации транзистора VT3, который, будучи кремниевым, требует минимальное напряжение 0,65 В для включения.
Однако, если выходная нагрузка превышает 100 мА, создается достаточно большой потенциал на транзисторе VT2, чтобы переключить транзистор VT3 в состояние проводимости. В результате транзистор VT3 начинает проводить ток в направлении транзистора VT1, что регулирует общий ток в цепи. Это вызывает некоторое снижение выходного напряжения. По мере увеличения нагрузки, потенциал на резисторе R2 растет, что заставляет транзистор VT3 открываться еще активнее.
В результате, больший ток начинает проходить к транзистору VT1 и отрицательной шине через транзистор VT3 и нагрузку. Это дополнительно приводит к увеличению падения выходного напряжения. Даже если произойдет короткое замыкание на выходе транзистора VT3, он, скорее всего, переключится в состояние проводимости, что приведет к снижению выходного напряжения до нуля. Таким образом, выходной ток никогда не превысит предел в 100 мА.
Я рассмотрел простую схему, как работает защита от перегрузки, с защитой по току, которая срабатывает при коротком замыкании или превышении нагрузки.
Подписывайтесь на сайт, что бы не пропустить новые статьи. До новых встреч на моем сайте.
При выборе площадки для ставок важно учитывать репутацию оператора. Современный https://kenzoscat.ru/reyting-bk.html предлагает пользователям инновационные решения для комфортного беттинга. Игроки отмечают удобство мобильного приложения и быстрые выплаты.
Современный беттинг требует надежной платформы для комфортной игры. Проверенный https://nayazyke.ru/fonbet-obzor/ предлагает пользователям широкие возможности для ставок на спорт. Клиенты получают доступ к качественному сервису и привлекательным бонусам.
Dodgers star Shohei Ohtani suffers left shoulder injury during Game 2 of the World Series
kra12.cc
Los Angeles Dodgers superstar Shohei Ohtani suffered a shoulder injury before the Dodgers’ 4-2 win over the New York Yankees in Game 2 of the World Series Saturday.
The Japanese slugger sustained a left shoulder subluxation and will undergo more testing, Los Angeles Dodgers manager Dave Roberts said after the game, adding that the team is however “encouraged” about the injury.
https://kra012.cc
Площадка кракен
“The strength was great,” Roberts told reporters. “The range of motion good. So, we’re encouraged. But obviously I can’t speculate because we don’t get the scans yet. So, once we get the scans, we’ll know more. Again, with the strength, the range of motion good, that’s certainly a positive.
A shoulder subluxation occurs when “the humerus partially slides in and out of place quickly,” according to Johns Hopkins Medicine.
With the Dodgers up 4-1 in the bottom of the seventh inning, Ohtani attempted to steal second base but was thrown out to end the inning. Ohtani, however, stayed on the ground grimacing in pain and eventually walked off the field with trainers holding his left arm.
“Obviously when you get any one of your players that goes down, it’s concerning,” Roberts said. “But after kind of the range of motion, the strength test, I felt much better about it.”
According to the FOX broadcast, microphones picked up a conversation between Ohtani and trainers saying that his left shoulder appears to have popped out of its socket.
This weekend’s playoffs mark Ohtani’s first appearance in the postseason after he missed out in each of his six seasons with the Los Angeles Angels.
The star player is riding on a series of remarkable accomplishments in recent months, including hitting his 50th homer of the season and stealing his 50th base in the Dodgers’ victory over the Miami Marlins last Thursday. Ohtani went on to rack up his 51st of each stat by the end of the contest.
Современный беттинг требует надежного доступа к букмекерской платформе. Рекомендуем скачать сайт Бетера для комфортных ставок. Пользователи получают быстрый доступ ко всем разделам букмекера.
Growing outside of Dearborn
kraken зеркало
During the day, Yemeni coffeehouses function similar to many neighborhood spots. Patrons host meetings, college students study and others pop in for a quick cup to-go.
https://kraken3yvbvzmhytnrnuhsy772i6dfobofu652e27f5hx6y5cpj7rgyd.cc
kraken войти
But at night, they serve as de-facto living rooms, especially for young Muslims who don’t go to clubs and bar. From New York to Dallas, especially during the late nights of Ramadan, the crowd overflows into the street and you often have to yell to be heard inside. Some young Muslims even venture to the coffee shops in hopes of finding a life partner.
Nowhere is this coffeehouse culture more pronounced, and celebrated, than in Dearborn, Michigan, a suburb of Detroit and home to one of the largest Arab American communities in the United States.
Downtown Dearborn is peppered with different Yemeni coffee houses, which Howell said helped revitalize the Detroit area after the city became the largest municipality go to bankrupt in 2013. And it’s only growing.
“It’s become sort of contagious,” Howell said. “Several Yemeni entrepreneurs are opening coffee houses of their own, each with its own sort of style and atmosphere.”
The coffee chains have big ambitions beyond Dearborn. Qahwah House hopes to open another 20 to 30 locations in the next year, spanning across 12 states and Canada, Alhasbani said. They are also licensed out, but Alhasbani says he sets a high standard before agreeing to let anyone open a shop.
“We have too many people that come (asking me) they want to open. I have more than 10 different requests a day just to open this kind of business,” he said. “We don’t give anyone license until we make sure the person has the love for the brand and his mind and his heart in the Qahwah House.”
Another authentic Yemeni coffee chain, Haraz, also sees crowds of people throughout the day and night. They opened their first location in New York City last week — less than half a mile away from Qahwah House’s downtown Manhattan shop — and the franchisees plan to grow.
A giant meteorite boiled the oceans 3.2 billion years ago. Scientists say it was a ‘fertilizer bomb’ for life
русское гей порно
A massive space rock, estimated to be the size of four Mount Everests, slammed into Earth more than 3 billion years ago — and the impact could have been unexpectedly beneficial for the earliest forms of life on our planet, according to new research.
Typically, when a large space rock crashes into Earth, the impacts are associated with catastrophic devastation, as in the case of the demise of the dinosaurs 66 million years ago, when a roughly 6.2-mile-wide (10-kilometer) asteroid crashed off the coast of the Yucatan Peninsula in what’s now Mexico.
But Earth was young and a very different place when the S2 meteorite, estimated to have 50 to 200 times more mass than the dinosaur extinction-triggering Chicxulub asteroid, collided with the planet 3.26 billion years ago, according to Nadja Drabon, assistant professor of Earth and planetary sciences at Harvard University. She is also lead author of a new study describing the S2 impact and what followed in its aftermath that published Monday in the journal Proceedings of the National Academy of Sciences.
“No complex life had formed yet, and only single-celled life was present in the form of bacteria and archaea,” Drabon wrote in an email. “The oceans likely contained some life, but not as much as today in part due to a lack of nutrients. Some people even describe the Archean oceans as ‘biological deserts.’ The Archean Earth was a water world with few islands sticking out. It would have been a curious sight, as the oceans were probably green in color from iron-rich deep waters.”
When the S2 meteorite hit, global chaos ensued — but the impact also stirred up ingredients that might have enriched bacterial life, Drabon said. The new findings could change the way scientists understand how Earth and its fledgling life responded to bombardment from space rocks not long after the planet formed.
Dodgers star Shohei Ohtani suffers left shoulder injury during Game 2 of the World Series
kraken ссылка
Los Angeles Dodgers superstar Shohei Ohtani suffered a shoulder injury before the Dodgers’ 4-2 win over the New York Yankees in Game 2 of the World Series Saturday.
The Japanese slugger sustained a left shoulder subluxation and will undergo more testing, Los Angeles Dodgers manager Dave Roberts said after the game, adding that the team is however “encouraged” about the injury.
https://kra012.cc
kraken сайт
“The strength was great,” Roberts told reporters. “The range of motion good. So, we’re encouraged. But obviously I can’t speculate because we don’t get the scans yet. So, once we get the scans, we’ll know more. Again, with the strength, the range of motion good, that’s certainly a positive.
A shoulder subluxation occurs when “the humerus partially slides in and out of place quickly,” according to Johns Hopkins Medicine.
With the Dodgers up 4-1 in the bottom of the seventh inning, Ohtani attempted to steal second base but was thrown out to end the inning. Ohtani, however, stayed on the ground grimacing in pain and eventually walked off the field with trainers holding his left arm.
“Obviously when you get any one of your players that goes down, it’s concerning,” Roberts said. “But after kind of the range of motion, the strength test, I felt much better about it.”
According to the FOX broadcast, microphones picked up a conversation between Ohtani and trainers saying that his left shoulder appears to have popped out of its socket.
This weekend’s playoffs mark Ohtani’s first appearance in the postseason after he missed out in each of his six seasons with the Los Angeles Angels.
The star player is riding on a series of remarkable accomplishments in recent months, including hitting his 50th homer of the season and stealing his 50th base in the Dodgers’ victory over the Miami Marlins last Thursday. Ohtani went on to rack up his 51st of each stat by the end of the contest.
Dodgers star Shohei Ohtani suffers left shoulder injury during Game 2 of the World Series
kraken тор браузер
Los Angeles Dodgers superstar Shohei Ohtani suffered a shoulder injury before the Dodgers’ 4-2 win over the New York Yankees in Game 2 of the World Series Saturday.
The Japanese slugger sustained a left shoulder subluxation and will undergo more testing, Los Angeles Dodgers manager Dave Roberts said after the game, adding that the team is however “encouraged” about the injury.
https://kra012.cc
kra cc
“The strength was great,” Roberts told reporters. “The range of motion good. So, we’re encouraged. But obviously I can’t speculate because we don’t get the scans yet. So, once we get the scans, we’ll know more. Again, with the strength, the range of motion good, that’s certainly a positive.
A shoulder subluxation occurs when “the humerus partially slides in and out of place quickly,” according to Johns Hopkins Medicine.
With the Dodgers up 4-1 in the bottom of the seventh inning, Ohtani attempted to steal second base but was thrown out to end the inning. Ohtani, however, stayed on the ground grimacing in pain and eventually walked off the field with trainers holding his left arm.
“Obviously when you get any one of your players that goes down, it’s concerning,” Roberts said. “But after kind of the range of motion, the strength test, I felt much better about it.”
According to the FOX broadcast, microphones picked up a conversation between Ohtani and trainers saying that his left shoulder appears to have popped out of its socket.
This weekend’s playoffs mark Ohtani’s first appearance in the postseason after he missed out in each of his six seasons with the Los Angeles Angels.
The star player is riding on a series of remarkable accomplishments in recent months, including hitting his 50th homer of the season and stealing his 50th base in the Dodgers’ victory over the Miami Marlins last Thursday. Ohtani went on to rack up his 51st of each stat by the end of the contest.
https://images.google.com.cy/url?sa=t&url=https://studio-sign.ru
https://www.google.it/url?sa=t&url=https://studio-sign.ru
https://toolbarqueries.google.com.ar/url?sa=t&url=https://studio-sign.ru
https://cse.google.as/url?sa=t&url=https://studio-sign.ru
https://toolbarqueries.google.co.za/url?sa=t&url=https://studio-sign.ru
https://maps.google.td/url?sa=t&url=https://studio-sign.ru
https://maps.google.com.au/url?sa=t&url=https://studio-sign.ru
https://maps.google.com.na/url?sa=t&url=https://studio-sign.ru
https://cse.google.lu/url?sa=t&url=https://studio-sign.ru
https://images.google.nu/url?sa=t&url=https://studio-sign.ru
https://cse.google.com.pk/url?sa=t&url=https://studio-sign.ru
https://www.google.mu/url?sa=t&url=https://studio-sign.ru
https://cse.google.dk/url?sa=t&url=https://studio-sign.ru
https://cse.google.cm/url?sa=t&url=https://studio-sign.ru
https://images.google.com.na/url?sa=t&url=https://studio-sign.ru
https://image.google.bf/url?sa=t&url=https://studio-sign.ru
https://maps.google.com.ag/url?sa=t&url=https://studio-sign.ru
https://images.google.hn/url?sa=t&url=https://studio-sign.ru
https://clients1.google.pt/url?sa=t&url=https://studio-sign.ru
https://maps.google.co.vi/url?sa=t&url=https://studio-sign.ru
A ring found among the debris of Florida’s recent hurricanes awaits its owner
kraken darknet
Scattered across Florida’s hurricane-ravaged communities are piles of debris, remnants of what were once homes. Cherished memories — photo albums, family heirlooms, and tokens of love — swallowed by floodwaters and carried miles away, are now reduced to mere fragments and discarded amid the wreckage.
But in one of these piles of lost memories, a small, inconspicuous velvet black box was discovered with a ring and a note that read: “I was 18 when my parents gave it to me.”
https://kra18c.cc
kraken shop
Now, Joe Kovach, the engineer managing one of the debris sites in Tarpon Springs, Florida, where the box was found, is searching for its owner.
“Everyone has been basically dumping their entire lives onto the curb after the storm when everything flooded. My own boss’ house had 30 inches (of water) in it, and I saw his face and just how devastating it can be for everyone,” Kovach, an engineer with Pinellas County Public Works, told CNN.
“A lot of people in the community were really affected by these two storms, if there’s just a little bit I can do to give back, then that’s perfect.”
A contractor, who was gathering and condensing debris with an excavator, discovered the ring when he looked down and saw the box.
“This was a needle in a haystack for sure. For something like that to survive all that when everything else was so wet and saturated, that was kind of incredible,” Kovach said.
Although the ring was found after Hurricane Milton, Kovach is sure the treasure was initially lost amid the ruins of Hurricane Helene, based on the pile of debris it came from, which Pinellas County Public Works tracks. It is likely the owner of the ring is from Crystal Beach, Ozona, or Palm Harbor, Kovach said.
On Tuesday, after the contractor informed him about the ring, Kovach posted a photo of the box and the note on several local community Facebook pages, asking if it belonged to anyone. He did not include a photo or description of the ring to ensure it is returned to the rightful owner who can accurately describe it. On the inside lid of the box is a gold engraving with the jewelry brand, “The Danbury Mint.”
пошукове просування у google