Register FAQ / Rules Forum Spy Search Today's Posts Mark Forums Read
Go Back   MacRumors Forums > Apple Hardware > Desktops > iMac

Reply
 
Thread Tools Search this Thread Display Modes
Old Apr 23, 2012, 05:58 AM   #1
sim667
macrumors 6502a
 
Join Date: Dec 2010
What would mac 30 macs unable to power on at the same time?

Came into work this morning, and none of the imacs would power on.

Tested the electricity trunking, all fine. It turned out they all needed the power cutting for 10 seconds, then they'd power on fine after that.

Would a power spike cause that?
__________________
Mac Pro, Macbook Pro, G4 Powerbook, iPad 4, iPhone 5, 2X TV, Nikon D800, ACSP Trained - Photography and Mac tech
Music and UK festival Blog
sim667 is offline   0 Reply With Quote
Old Apr 23, 2012, 06:12 AM   #2
mulo
macrumors 68020
 
mulo's Avatar
 
Join Date: Aug 2010
Location: Behind you
Send a message via MSN to mulo
knowing nothing about it i would think a spike would cause some "safety switch" to trigger, then requiring power off
__________________
iPhone 5 Black 64GB.
17" MBP 2.2GHz i7, 16GB RAM.
Canon 7D + grip, 24-70mm f/2.8L USM, 70-200mm f/2.8L IS USM.
mulo is offline   0 Reply With Quote
Old Apr 23, 2012, 06:15 AM   #3
All Taken
macrumors 6502a
 
Join Date: Dec 2009
Location: UK
Quote:
Originally Posted by sim667 View Post
Came into work this morning, and none of the imacs would power on.

Tested the electricity trunking, all fine. It turned out they all needed the power cutting for 10 seconds, then they'd power on fine after that.

Would a power spike cause that?
They were all asleep and you didn't give them enough time to 'wake'?

Your wiring is faulty and not enough power was being received to power the machines after they had shut down due to perhaps a power cut, when you reset the power it supplied the correct load. Check your wiring for faults?

Thats my best guesses
All Taken is offline   0 Reply With Quote
Old Apr 23, 2012, 07:14 AM   #4
sim667
Thread Starter
macrumors 6502a
 
Join Date: Dec 2010
Quote:
Originally Posted by All Taken View Post
They were all asleep and you didn't give them enough time to 'wake'?

Your wiring is faulty and not enough power was being received to power the machines after they had shut down due to perhaps a power cut, when you reset the power it supplied the correct load. Check your wiring for faults?

Thats my best guesses
They definately weren't asleep..... I've been looking after macs for a long long time.

Wiring is fine, we've had an electirican out to check it all...

Im guessing there was a power spike over the weekend.
__________________
Mac Pro, Macbook Pro, G4 Powerbook, iPad 4, iPhone 5, 2X TV, Nikon D800, ACSP Trained - Photography and Mac tech
Music and UK festival Blog
sim667 is offline   0 Reply With Quote
Old Apr 23, 2012, 07:59 AM   #5
mus0r
macrumors regular
 
Join Date: Mar 2005
Reset the power management.
__________________
2012 Mini with Fusion drive
2012 MacBook Pro
120GB iPod Classic
mus0r is offline   0 Reply With Quote
Old Apr 23, 2012, 08:44 AM   #6
iMacC2D
macrumors 6502
 
Join Date: Jun 2010
Quote:
Originally Posted by sim667 View Post
Tested the electricity trunking, all fine. It turned out they all needed the power cutting for 10 seconds, then they'd power on fine after that.
Sounds like a power fluctuation of some sort caused the SMC (System Management Controller) to stop functioning correctly. Disconnecting the power for about 10-15 seconds and reapplying power is how you reset the SMC on an iMac.
iMacC2D is offline   0 Reply With Quote
Old Apr 23, 2012, 09:27 AM   #7
sparkie1984
macrumors 65816
 
Join Date: Dec 2009
Location: laandan uk
It's too much load powering all on at once.

When we do computer rooms you need to install a breaker to take a large start up current.
sparkie1984 is online now   0 Reply With Quote
Old Apr 24, 2012, 04:02 AM   #8
sim667
Thread Starter
macrumors 6502a
 
Join Date: Dec 2010
Quote:
Originally Posted by sparkie1984 View Post
It's too much load powering all on at once.

When we do computer rooms you need to install a breaker to take a large start up current.
That might be it, all our computers are set to boot up at 8.30am

We've never had the problem before...... Ill have to keep an eye on it.
__________________
Mac Pro, Macbook Pro, G4 Powerbook, iPad 4, iPhone 5, 2X TV, Nikon D800, ACSP Trained - Photography and Mac tech
Music and UK festival Blog
sim667 is offline   0 Reply With Quote
Old Apr 24, 2012, 04:27 AM   #9
sparkie1984
macrumors 65816
 
Join Date: Dec 2009
Location: laandan uk
Could be playing up now due to excessive wear on the breaker.

As a qualified electrician that's where I'd be looking first, had it before at schools

Could you stagger their turn on times
sparkie1984 is online now   0 Reply With Quote
Old Apr 24, 2012, 04:30 AM   #10
Macman45
macrumors G5
 
Macman45's Avatar
 
Join Date: Jul 2011
Location: Somewhere Back In The Long Ago
Quote:
Originally Posted by sim667 View Post
They definately weren't asleep..... I've been looking after macs for a long long time.

Wiring is fine, we've had an electirican out to check it all...

Im guessing there was a power spike over the weekend.
Yep, we had this a while back here too....Depending on your power settings for the machines, I'd say that's exactly what happened...A spike or a brown out. I'm guessing you are surge protected so no damage will have been done, but re-setting SMC on them would be a good idea.
__________________
Thats Not All Folks
Macman45 is offline   0 Reply With Quote
Old Apr 24, 2012, 10:36 AM   #11
mlts22
macrumors 6502
 
Join Date: Oct 2008
I'd reset the SMC. To make things easier, can the OP stagger the time the Macs come on? This way, the initial inrush of everything starting (inrush current to spin up HDDs and fans) isn't hitting the circuit all at once.
mlts22 is offline   0 Reply With Quote
Old Apr 30, 2012, 06:24 AM   #12
sim667
Thread Starter
macrumors 6502a
 
Join Date: Dec 2010
Quote:
Originally Posted by mlts22 View Post
I'd reset the SMC. To make things easier, can the OP stagger the time the Macs come on? This way, the initial inrush of everything starting (inrush current to spin up HDDs and fans) isn't hitting the circuit all at once.
Im not the actual tech, but ill suggest it to them
__________________
Mac Pro, Macbook Pro, G4 Powerbook, iPad 4, iPhone 5, 2X TV, Nikon D800, ACSP Trained - Photography and Mac tech
Music and UK festival Blog
sim667 is offline   0 Reply With Quote

Reply
MacRumors Forums > Apple Hardware > Desktops > iMac

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Similar Threads
thread Thread Starter Forum Replies Last Post
Power Nap on all Macs with SSD's Possible? PhixionFilms OS X 10.8 Mountain Lion 10 Feb 4, 2014 02:21 AM
I am unable to power down before repair akersrus iPad Tips, Help and Troubleshooting 5 Sep 8, 2013 02:39 PM
Time machine for two Macs, plugged to Mac Mini r6mile Mac mini 7 Jun 2, 2013 02:02 AM
Technical question: Time Capsule and Power Mac G5 hoya87eagle91 Mac Peripherals 1 Dec 19, 2012 02:05 AM

Forum Jump

All times are GMT -5. The time now is 03:16 AM.

Mac Rumors | Mac | iPhone | iPhone Game Reviews | iPhone Apps

Mobile Version | Fixed | Fluid | Fluid HD
Copyright 2002-2013, MacRumors.com, LLC