iMac turned itself on after power was cut
I left my computer sleeping but turned off the power by accident. Hours after the power was turned back on the computer booted itself up. It is plugged into a UPS. I don't understand how this could happen.
imac
edited Dec 31 '18 at 13:19
wizzwizz4
1086
asked Dec 31 '18 at 7:33
Debra
311
New contributor
Debra is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |
I left my computer sleeping but turned off the power by accident. Hours after the power was turned back on the computer booted itself up. It is plugged into a UPS. I don't understand how this could happen.
imac
edited Dec 31 '18 at 13:19
wizzwizz4
1086
asked Dec 31 '18 at 7:33
Debra
311
New contributor
Debra is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Is the "start on power" selected in the system preferences? if so it will start on getting power...
– Solar Mike
Dec 31 '18 at 8:54
December 30, 2018. Skynet becomes self aware.
– Terminator
Jan 1 at 1:07
add a comment |
I left my computer sleeping but turned off the power by accident. Hours after the power was turned back on the computer booted itself up. It is plugged into a UPS. I don't understand how this could happen.
imac
edited Dec 31 '18 at 13:19
wizzwizz4
1086
asked Dec 31 '18 at 7:33
Debra
311
New contributor
Debra is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
I left my computer sleeping but turned off the power by accident. Hours after the power was turned back on the computer booted itself up. It is plugged into a UPS. I don't understand how this could happen.
imac
imac
edited Dec 31 '18 at 13:19
wizzwizz4
1086
asked Dec 31 '18 at 7:33
Debra
311
New contributor
Debra is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
edited Dec 31 '18 at 13:19
wizzwizz4
1086
asked Dec 31 '18 at 7:33
Debra
311
New contributor
Debra is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
edited Dec 31 '18 at 13:19
wizzwizz4
1086
edited Dec 31 '18 at 13:19
wizzwizz4
1086
edited Dec 31 '18 at 13:19
wizzwizz4
1086
1086
asked Dec 31 '18 at 7:33
Debra
311
New contributor
Debra is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked Dec 31 '18 at 7:33
Debra
311
asked Dec 31 '18 at 7:33
Debra
311
311
New contributor
Debra is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
Debra is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Debra is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Is the "start on power" selected in the system preferences? if so it will start on getting power...
– Solar Mike
Dec 31 '18 at 8:54
December 30, 2018. Skynet becomes self aware.
– Terminator
Jan 1 at 1:07
add a comment |
Is the "start on power" selected in the system preferences? if so it will start on getting power...
– Solar Mike
Dec 31 '18 at 8:54
December 30, 2018. Skynet becomes self aware.
– Terminator
Jan 1 at 1:07
Is the "start on power" selected in the system preferences? if so it will start on getting power...
– Solar Mike
Dec 31 '18 at 8:54
Is the "start on power" selected in the system preferences? if so it will start on getting power...
– Solar Mike
Dec 31 '18 at 8:54
December 30, 2018. Skynet becomes self aware.
– Terminator
Jan 1 at 1:07
December 30, 2018. Skynet becomes self aware.
– Terminator
Jan 1 at 1:07
add a comment |
1 Answer
1
active
oldest
votes
On the iMac, there's a setting under System Preferences > Energy Saver called Start up automatically after a power failure, which I'm guessing will be selected on your system, and hence would explain your computer's spontaneous rebooting.
If you don't wish this to happen in the event of a power failure, or the next time you turn off the power by accident, then uncheck that particular option.
Note: Screenshot taken on macOS 10.12.6 (Sierra)
As Tetsujin very helpfully points out in the comments below, there is also a button in the bottom right of the Energy Saver preferences pane labelled "Schedule...", which allows the user to regulate when the computer starts up, wakes up, or goes to sleep. It would be wise to double check your settings there too.
answered Dec 31 '18 at 8:56
CJK
2,658114
1
There's also the Schedule, bottom right, which could potentially explain why it switched on hours later.
– Tetsujin
Dec 31 '18 at 9:09
1
Thanks @Tetsujin. I misread the OP as saying "Hours_later_, the power was turned back on...". I'll add your comment to the answer, as it's a very pertinent detail.
– CJK
Dec 31 '18 at 9:29
1
There is also the remote possibility that the UPS spent the first few hours recharging before pushing power to the Mac, but I don't know enough about UPS to know if that's a valid suggestion.
– Tetsujin
Dec 31 '18 at 9:33
@Tetsujin yes, for a ups that can happen - depends how it can be configured... sure the answer will get updated to include that...
– Solar Mike
Dec 31 '18 at 10:56
add a comment |
Your Answer
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "118"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: false,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: null,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Debra is a new contributor. Be nice, and check out our Code of Conduct.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fapple.stackexchange.com%2fquestions%2f347122%2fimac-turned-itself-on-after-power-was-cut%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
On the iMac, there's a setting under System Preferences > Energy Saver called Start up automatically after a power failure, which I'm guessing will be selected on your system, and hence would explain your computer's spontaneous rebooting.
If you don't wish this to happen in the event of a power failure, or the next time you turn off the power by accident, then uncheck that particular option.
Note: Screenshot taken on macOS 10.12.6 (Sierra)
As Tetsujin very helpfully points out in the comments below, there is also a button in the bottom right of the Energy Saver preferences pane labelled "Schedule...", which allows the user to regulate when the computer starts up, wakes up, or goes to sleep. It would be wise to double check your settings there too.
answered Dec 31 '18 at 8:56
CJK
2,658114
1
There's also the Schedule, bottom right, which could potentially explain why it switched on hours later.
– Tetsujin
Dec 31 '18 at 9:09
1
Thanks @Tetsujin. I misread the OP as saying "Hours_later_, the power was turned back on...". I'll add your comment to the answer, as it's a very pertinent detail.
– CJK
Dec 31 '18 at 9:29
1
There is also the remote possibility that the UPS spent the first few hours recharging before pushing power to the Mac, but I don't know enough about UPS to know if that's a valid suggestion.
– Tetsujin
Dec 31 '18 at 9:33
@Tetsujin yes, for a ups that can happen - depends how it can be configured... sure the answer will get updated to include that...
– Solar Mike
Dec 31 '18 at 10:56
add a comment |
On the iMac, there's a setting under System Preferences > Energy Saver called Start up automatically after a power failure, which I'm guessing will be selected on your system, and hence would explain your computer's spontaneous rebooting.
If you don't wish this to happen in the event of a power failure, or the next time you turn off the power by accident, then uncheck that particular option.
Note: Screenshot taken on macOS 10.12.6 (Sierra)
As Tetsujin very helpfully points out in the comments below, there is also a button in the bottom right of the Energy Saver preferences pane labelled "Schedule...", which allows the user to regulate when the computer starts up, wakes up, or goes to sleep. It would be wise to double check your settings there too.
answered Dec 31 '18 at 8:56
CJK
2,658114
1
There's also the Schedule, bottom right, which could potentially explain why it switched on hours later.
– Tetsujin
Dec 31 '18 at 9:09
1
Thanks @Tetsujin. I misread the OP as saying "Hours_later_, the power was turned back on...". I'll add your comment to the answer, as it's a very pertinent detail.
– CJK
Dec 31 '18 at 9:29
1
There is also the remote possibility that the UPS spent the first few hours recharging before pushing power to the Mac, but I don't know enough about UPS to know if that's a valid suggestion.
– Tetsujin
Dec 31 '18 at 9:33
@Tetsujin yes, for a ups that can happen - depends how it can be configured... sure the answer will get updated to include that...
– Solar Mike
Dec 31 '18 at 10:56
add a comment |
On the iMac, there's a setting under System Preferences > Energy Saver called Start up automatically after a power failure, which I'm guessing will be selected on your system, and hence would explain your computer's spontaneous rebooting.
If you don't wish this to happen in the event of a power failure, or the next time you turn off the power by accident, then uncheck that particular option.
Note: Screenshot taken on macOS 10.12.6 (Sierra)
As Tetsujin very helpfully points out in the comments below, there is also a button in the bottom right of the Energy Saver preferences pane labelled "Schedule...", which allows the user to regulate when the computer starts up, wakes up, or goes to sleep. It would be wise to double check your settings there too.
answered Dec 31 '18 at 8:56
CJK
2,658114
On the iMac, there's a setting under System Preferences > Energy Saver called Start up automatically after a power failure, which I'm guessing will be selected on your system, and hence would explain your computer's spontaneous rebooting.
If you don't wish this to happen in the event of a power failure, or the next time you turn off the power by accident, then uncheck that particular option.
Note: Screenshot taken on macOS 10.12.6 (Sierra)
As Tetsujin very helpfully points out in the comments below, there is also a button in the bottom right of the Energy Saver preferences pane labelled "Schedule...", which allows the user to regulate when the computer starts up, wakes up, or goes to sleep. It would be wise to double check your settings there too.
answered Dec 31 '18 at 8:56
CJK
2,658114
edited Dec 31 '18 at 9:36
answered Dec 31 '18 at 8:56
CJK
2,658114
answered Dec 31 '18 at 8:56
CJK
2,658114
answered Dec 31 '18 at 8:56
CJK
2,658114
2,658114
1
There's also the Schedule, bottom right, which could potentially explain why it switched on hours later.
– Tetsujin
Dec 31 '18 at 9:09
1
Thanks @Tetsujin. I misread the OP as saying "Hours_later_, the power was turned back on...". I'll add your comment to the answer, as it's a very pertinent detail.
– CJK
Dec 31 '18 at 9:29
1
There is also the remote possibility that the UPS spent the first few hours recharging before pushing power to the Mac, but I don't know enough about UPS to know if that's a valid suggestion.
– Tetsujin
Dec 31 '18 at 9:33
@Tetsujin yes, for a ups that can happen - depends how it can be configured... sure the answer will get updated to include that...
– Solar Mike
Dec 31 '18 at 10:56
add a comment |
1
There's also the Schedule, bottom right, which could potentially explain why it switched on hours later.
– Tetsujin
Dec 31 '18 at 9:09
1
Thanks @Tetsujin. I misread the OP as saying "Hours_later_, the power was turned back on...". I'll add your comment to the answer, as it's a very pertinent detail.
– CJK
Dec 31 '18 at 9:29
1
There is also the remote possibility that the UPS spent the first few hours recharging before pushing power to the Mac, but I don't know enough about UPS to know if that's a valid suggestion.
– Tetsujin
Dec 31 '18 at 9:33
@Tetsujin yes, for a ups that can happen - depends how it can be configured... sure the answer will get updated to include that...
– Solar Mike
Dec 31 '18 at 10:56
1
1
There's also the Schedule, bottom right, which could potentially explain why it switched on hours later.
– Tetsujin
Dec 31 '18 at 9:09
There's also the Schedule, bottom right, which could potentially explain why it switched on hours later.
– Tetsujin
Dec 31 '18 at 9:09
1
1
Thanks @Tetsujin. I misread the OP as saying "Hours_later_, the power was turned back on...". I'll add your comment to the answer, as it's a very pertinent detail.
– CJK
Dec 31 '18 at 9:29
Thanks @Tetsujin. I misread the OP as saying "Hours_later_, the power was turned back on...". I'll add your comment to the answer, as it's a very pertinent detail.
– CJK
Dec 31 '18 at 9:29
1
1
There is also the remote possibility that the UPS spent the first few hours recharging before pushing power to the Mac, but I don't know enough about UPS to know if that's a valid suggestion.
– Tetsujin
Dec 31 '18 at 9:33
There is also the remote possibility that the UPS spent the first few hours recharging before pushing power to the Mac, but I don't know enough about UPS to know if that's a valid suggestion.
– Tetsujin
Dec 31 '18 at 9:33
@Tetsujin yes, for a ups that can happen - depends how it can be configured... sure the answer will get updated to include that...
– Solar Mike
Dec 31 '18 at 10:56
@Tetsujin yes, for a ups that can happen - depends how it can be configured... sure the answer will get updated to include that...
– Solar Mike
Dec 31 '18 at 10:56
add a comment |
Debra is a new contributor. Be nice, and check out our Code of Conduct.
Debra is a new contributor. Be nice, and check out our Code of Conduct.
Debra is a new contributor. Be nice, and check out our Code of Conduct.
Debra is a new contributor. Be nice, and check out our Code of Conduct.
Thanks for contributing an answer to Ask Different!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Some of your past answers have not been well-received, and you're in danger of being blocked from answering.
Please pay close attention to the following guidance:
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fapple.stackexchange.com%2fquestions%2f347122%2fimac-turned-itself-on-after-power-was-cut%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Is the "start on power" selected in the system preferences? if so it will start on getting power...
– Solar Mike
Dec 31 '18 at 8:54
December 30, 2018. Skynet becomes self aware.
– Terminator
Jan 1 at 1:07