iMac (27-inch, Mid 2010) Take Apart — General Information 133
2010-09-09
Safety
Warning: HIGH VOLTAGE: The AC/DC power supply PCB remains powered up whenever the
system is plugged in, whether or not the system has been turned on. Use extreme caution
when troubleshooting the system with the front bezel removed.
• Don’t work alone. In the event of an electrical shock it is important to have another
individual present who can provide assistance.
• Keep one hand in your pocket when working on any iMac system that is plugged in.
This will help ensure that your body does not provide a path to ground in the event
that you accidentally make contact with the line voltage.
• Don’t wear jewelry, watches, necklaces, or other metallic articles that could present a
risk if they accidentally make contact with the power supply circuitry.
Use extreme caution when working around the power supply. The power supply contains a
high voltage capacitor that may remain charged for several minutes even when the computer is
unplugged. Never touch the leads on the top side of the power supply, especially the capacitor
leads located near the warning sign
Important: If the computer is shut down by removing the power cord, allow the power supply
a good 2-3 minutes to discharge the capacitors before handling it. However, if you select “Shut
Down” via the Apple menu, the computer will discharge the power supply capacitor almost
immediately.