OT: computer blowing breakers

I recently got a Mac Pro; the power ratings say 12A max. The breaker for my office is 15A. I've got a lot of equipment in the office, but even when it's all off, starting up the Mac and display blows the breaker about 1/2 the time.

I configured the monitor so that it can be turned on separately; I unplugged (not just turned off) all other peripherals (printer, scanner, etc.) Still happens about 1 time in 5, and that's with only the CPU and display. Waking up from sleep mode is no different than starting up from a complete power down.

Before I went 'unplugged' in the office, I blew a p/s on a nice TV (which was on a surge protector itself, though not as robust as the one I use for the computer).

I'm seriously thinking about returning it. I've got a power-up sequence in the office that reminds me of the Apollo 13 movie. And that's w/o the peripherals which I've kept unplugged because I haven't downloaded Mac drivers yet.

I'm mostly venting, but if anyone has any thoughts or suggestions, I'm all ears.

Man you got a real issue here! I'd first talk with an electrician who can see what can be done about the power load in your office. Also I would try the unit in another location before returning it to see if it blows breakers there too!

Not to make matters worse, but Apple usually charges a 10% "restocking fee" if you return it. However, they are also usually very reasonable. If you swap it out for a different one, I'm not sure that it would help. Sounds like your office may have issues with the wiring? If you decide to keep it and want to set up a RAID system, do so before loading the operating system (otherwise you'll end up having to create a scratch disk and then erasing all disks prior to loading the OS). If you need any mac help setting anything up, let me know.

Ouch. Sounds bad.

Most computers never draw their maximum power rating, not even during bootup. I have two PCs, a monitor, speakers, printer, routers and switches, and a synth all tied in to a single 15 or 20A circuit, and never have any issues with power. Most server hosting areas host 4 servers on a single 30A circuit.

I agree with James's input - take it to another 15A circuit and see if it blows that one, too. If it does, take the system back to the dealer for an exchange - it's a dud. If not, your "15A" circuit is a dud and needs an electrician.

Rick,

Again, like Les, I agree that the 12A load for the computer is max load. You shouldn't be having these problems with your Mac. It should very rarely be touching max load.

I'd look at the following.

Find another 15A circuit in your house and boot the mac on that circuit. Then find a 20A circuit and do the same. If the Mac is still popping the circuit, suspect the Mac. Mac should replace the power supply and any other faulty equipment at no charge.

If it is OK on another 15A circuit (which it should be) you should talk to an electrician. You may have a wiring problem in your house, or that wiring in the office may be attached to more than you think. Ask the electrician if the circuit breaker can be upgraded to a 20A or 30A breaker with the wiring that is in place. Also, remember that you probably have lights in your office. Are they on the same circuit? Can they be moved to another circuit?

Good luck with your electrical issues. Also, look into adding a battery backup/UPS. This would allow your computer to shut down smoothly when you lose power.

I think Mel may have hit there, you probably have more attached to that circuit than you think. I have a freezer in my basement that is on the same circuit as one in the garage, I used a mitersaw once blew the circuit but didn't know the freezer was on it till about 3 days later when I went to get some meat out for dinner. Threw away about 250.00 in meat and other frozen food. I'd check the house for issues. Unless you wired the office yourself, it is probably got something else on it. Just my 2 cents................J

Sounds like you have got some great advice already. That 12A max is hardly ever reached. I would be amazed if your ever hitting 10A and after they are started they are probably running in the 3 - 6A range. I've got about 10 + servers, swithes, access points, and other crap all on a 20A circuit and have never blown it. I would have to say either there is something wrong with your wiring or like people mentioned above you have something else on that circuit. To find out you could get you one of those devices that measures load and spike AMPs. You could plug everthing into that and see what you are really pulling. My surge protector for my Servers has a AMP, Peak, and more LCD display so I can see what's going on. Hope this helps.

Brian

Well, I took it to the Mac store to talk to someone; he said bring it in and we'll test it. I went home, boxed it up, took it back and the guy I originally talked to was gone; the "Genius" (their term, not mine...) on duty plugged it in, turned it on and since the store didn't go dark he thinks it's 'good'.

I'm in the process of moving it around the house with the display testing circuits. The manager said if I blow other circuits in the house, he'll swap CPUs. If it still blows, they'll 'work something out with me'. That doesn't sound encouraging; I suspect they'll "work out" a 10% restocking fee.

Thanks for the suggestions. I'm going to ask an electrician friend about putting in a 20 or 25A breaker without having to mess with wiring or violating code. The house is new - 3 yrs old and wired for everything; can't believe that there's CAT 5 wiring, ports everywhere, pre-wired home theatre and....15A breakers. But I suspect that you guys are right that there's something else connected to my office other than my office. Probably the washing machine...

I appreciate the help! I'll let you know how it turns out.

Rick, I'm not an electrician although when I built my house in 1990 I did the electrical, so I do know a little about house wiring, circuits, etc. First off, you can not add a 20A breaker onto a 15A circuit, that is a code violation, and the reason is that it could start a fire. All home 15A circuits are wired with what is called 14-2 NM wire (14gauge wire with 1 black wire,1 white wire, and 1 bare ground wire). A home 20A circuit is wired with a minimum of 12-2 NM wire (12gauge with 1 black,1white,and 1 bare wire). The NM stands for non-metallic and describes the sheath that wraps the wire. Most lighting circuits and power outlets in the typical home use 14-2 wire and is hooked to a 15A circuit breaker. 20A circuit breakers are usually reserved for heavy duty use, such that you will have one 20A circuit for your trash compactor, another for your whirlpool tub, another for the garage (power tools), and one for the refrigerator (although some only require a 15A circuit). If the contractor is thinking ahead or the home owner requests it, they will put in a dedicated 20A circuit for special uses, such as computers, high end stereo equipment,etc. The only way I can see that your lone computer is popping a 15A circuit breaker is 1)a short in the computer 2) other appliances or loads on that circuit. A good idea for all home owners is to have a chart by the breaker box listing every light and outlet that each breaker controls. Be aware that most circuits are set up such that one breaker will control not only the lights in one room but one or more power outlets in different parts of the house. The idea being that power loads can be spread out more easily over various power demands at any one time. There are also GFCI (Ground Fault Circuit Interrupter) power outlets that also regulate specific circuits in houses, these are the outlets with the 2 differently colored push buttons between the actual outlet pair. They control outlets that are within 6 feet of a water source, all outdoor outlets, and all garage outlets. They are not needed in typical light/power outlet circuits unless part of the circuit is in one of the above three defined areas. There are 15A GFCI's as well as 20A GFCI's and the proper rated GFCI needs to be used in the appropriate house circuit.
Considering your house is 3years old and you have typical loads on the circuit your computer is hooked up on, my guess is a possible faulty power supply in the computer. Maybe you could get an electrician to validate your popping circuit breaker problem to help convince the computer dealer that it's not a house wiring problem. Your dealer by the way is more than likely on 20A circuits.
Hope this helps.
Don

Rick,

If the guy at the store gives you any crap, well - there's usually a lot of people in a computer store looking to buy expensive things; chances are, if you start talking "defective" and "warranty", they'll stop talking "I'll see what I can do...". It's not pleasant, but computer stores aren't supposed to sell defective computers.

Hopefully, though, it's just an overloaded circuit.

Thanks, Don and Les. The wiring is 14-2, so no going with a higher rated breaker. I agree - it's likely other loads on that circuit that push it over 15A when the Mac starts up. They swapped out my CPU and it did the same thing. The only time it wouldn't blow the breaker was when I had nothing but the CPU and display powering up. As soon as I added anything to the circuit (e.g., scanner, printer, etc.), starting up the computer would blow the breaker.

I took the Mac back. :sad: I asked several times if any other customers reported this problem (I found several forums on line where this problem had been discussed). Despite being generally helpful, they never answered and just continued asking me questions. I'll get the circuit checked when I can (I don't think it's anything more than just loading with more than 15A), but in the meantime I got a Dell with twice the RAM (4GB vs 2 in the Mac), 4x the storage (1TB vs 250GB) and a 24" widescreen for $1000 less than the Mac Pro.