即使设置为从不休眠，iMac也会休眠

运行10.7.5，我有一台相当新的iMac（6个月大）27英寸，设置为永不睡眠，但是今天早上上班时它已经睡着了。如何解决此问题？

终端中pmset -g的输出：

Active Profiles:
AC Power        -1*
Currently in use:
 autorestart    0
 powerbutton    0
 halfdim    1
 panicrestart   157680000
 hibernatefile  /var/vm/sleepimage
 networkoversleep   0
 disksleep  0
 sleep      0 (imposed by 139)
 hibernatemode  0
 ttyskeepawake  1
 displaysleep   15
 womp       1

以及/ Library / Preferences / SystemConfiguration中com.apple.PowerManagement.plist的内容：

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>ActivePowerProfiles</key>
    <dict>
        <key>AC Power</key>
        <integer>-1</integer>
    </dict>
    <key>Custom Profile</key>
    <dict>
        <key>AC Power</key>
        <dict>
            <key>Automatic Restart On Power Loss</key>
            <integer>0</integer>
            <key>Disk Sleep Timer</key>
            <integer>0</integer>
            <key>Display Sleep Timer</key>
            <integer>15</integer>
            <key>Display Sleep Uses Dim</key>
            <integer>1</integer>
            <key>Hibernate File</key>
            <string>/var/vm/sleepimage</string>
            <key>Hibernate Mode</key>
            <integer>0</integer>
            <key>PrioritizeNetworkReachabilityOverSleep</key>
            <integer>0</integer>
            <key>RestartAfterKernelPanic</key>
            <integer>157680000</integer>
            <key>Sleep On Power Button</key>
            <false/>
            <key>System Sleep Timer</key>
            <integer>0</integer>
            <key>TTYSPreventSleep</key>
            <integer>1</integer>
            <key>Wake On LAN</key>
            <integer>1</integer>
        </dict>
    </dict>
    <key>LastSleepUUID</key>
    <dict>
        <key>Date</key>
        <date>2012-12-06T04:39:59Z</date>
        <key>UUID</key>
        <string>019EBED9-FE31-4B63-8D7A-99F41B6EB618</string>
    </dict>
</dict>
</plist>

如您所见，它具有今天早上4:39入睡的记录，但是所有设置还显示它已设置为“不入睡”。有什么想法吗？

您是否可能设置了使系统休眠的时间表？系统偏好设置>节能>计划按钮，或者pmset -g sched（仅sched）。