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Resolved Power Surge Nightmare!

tevion5

tevion5

macrumors 68000
Original poster
Jul 12, 2011
1,967
1,603
Ireland
I have a reasonably large computer collection consisting of many many Macintosh systems and two Commodores. While very few of them are ever on at one time, I always leave them connected to mains power when off.

Being all in my room, I do not have 20 power sockets on the walls for all the various adapters, routers, monitors and computers. As a result I have employed the use of 2-3 extension leads (with surge protection) to allow everything to remain plugged in for when I want to use it, be it my 512K or Apple II, to my Quicksilver or iMac G3.

However, just recently in the last month or so, my house has been experiencing random power cuts with the trip switch needing to reset. The source is from my floor of the house, and my room is the only considerable suspect. I have left my room disconnected while I am away at college and when I do there seems to be no issue with the power cuts.

Okay, but what i don't understand is:
A) why this was never a problem for over a year before,
B) why this is happening when all devices are off, and
C) which device is the culprit!

My iMac G3 being the latest addition is the first place I went, as I got it shortly before the power cuts started to happen. But when I disconnected it from the array, we still got cuts.

Now I have theorised that it could be the voltage step down adapters that I use for my American 115V Macintosh 512Ke and Apple II Plus. They are technically on all the time, even if their respective devices are not. They do get hot and emit a high pitched tone when in use for a long time alright.

Having to turn off all the networking devices (including my upstairs AirPort Express!) in my room every week is driving me mad.

Any ideas guys? :confused:
 
More than likely that room and possibly another are all on a single 20 amp breaker. You're going to drawing quite a bit if you've got several CRT displays. I can throw a breaker with a halogen ceiling fixture on, the quad G5, and a small oil radiator. Now if you're having the thing trip when there is NOTHING running, then it may be a bad extension cable, a short, or even a failing breaker causing that.
 
Have you considered having your power-supply personnel come out and check your actual level of power?
 
Hrududu said:
More than likely that room and possibly another are all on a single 20 amp breaker. You're going to drawing quite a bit if you've got several CRT displays. I can throw a breaker with a halogen ceiling fixture on, the quad G5, and a small oil radiator. Now if you're having the thing trip when there is NOTHING running, then it may be a bad extension cable, a short, or even a failing breaker causing that.
Click to expand...

Ireland might be different from the UK but round our way I believe 30A is the usual load on a circuit before it trips, which gives a little more breathing room. I shudder to think how many things are plugged in on various surge strips and towers in my computer/dump/storage room but so far it seems to cope with aplomb.

I might suspect one of the surge devices, especially if they are cheap consumer units and come with rocker switches. Too many of those are not designed with heavy loads in mind and the heat generated is often enough to warp/fuse the rocker switch. So far I have lost two to that.
 
Any machine that doesn't have a power switch on the back could be the culprit, along with your step down tranformer and 'surge protection' power boards.

One that still makes me cringe was the 6200 (and it's variants) with a DynaComp power supply. They used to zap themselves with alarming regularity.

Ultimately the only course might be to disconnect half of the devices at a time. If it still trips you know it's the half you left connected. Then you halve those again.

I also recall a situation where the fault was old wiring which had a tiny trickle to the roof beam it was attached to. Only when an earth leakage circuit breaker was fitted to that circuit did the problem manifest itself in occasional tripping, and then only on humid or wet days when the timber became moistened.

BTW, most cheap surge protectors only have the SAME circuitry that a well made computer power supply already has in it. They often are sold for a lot more than they're worth with claims of special insurance cover. Unless it's a line conditioner or UPS, it really isn't worth the cost.
 
tevion5 said:
I have a reasonably large computer collection consisting of many many Macintosh systems and two Commodores. While very few of them are ever on at one time, I always leave them connected to mains power when off.

Being all in my room, I do not have 20 power sockets on the walls for all the various adapters, routers, monitors and computers. As a result I have employed the use of 2-3 extension leads (with surge protection) to allow everything to remain plugged in for when I want to use it, be it my 512K or Apple II, to my Quicksilver or iMac G3.

However, just recently in the last month or so, my house has been experiencing random power cuts with the trip switch needing to reset. The source is from my floor of the house, and my room is the only considerable suspect. I have left my room disconnected while I am away at college and when I do there seems to be no issue with the power cuts.

Okay, but what i don't understand is:
A) why this was never a problem for over a year before,
B) why this is happening when all devices are off, and
C) which device is the culprit!

My iMac G3 being the latest addition is the first place I went, as I got it shortly before the power cuts started to happen. But when I disconnected it from the array, we still got cuts.

Now I have theorised that it could be the voltage step down adapters that I use for my American 115V Macintosh 512Ke and Apple II Plus. They are technically on all the time, even if their respective devices are not. They do get hot and emit a high pitched tone when in use for a long time alright.

Having to turn off all the networking devices (including my upstairs AirPort Express!) in my room every week is driving me mad.

Any ideas guys? :confused:
Click to expand...

I know off topic but man. Sounds like you're already living in heaven. lol
 
Kill all the other circuit breakers for your house and check what your room is pulling. Your circuit breaker could also be the culprit. Doing a swap is pretty inexpensive, but make sure you kill the main breaker so you don't risk your life on that one.
 
Check the paper filter capacitors in all the machines, it has been know that when these go bad they become leaky and can allow just enough power to flow to earth to trip RCD breakers.

Luckily these are easy to spot when the go bad, normally the casing on them starts cracking when they are bad. I tend to just replace them when restoring my machines these days

It's also worth noting that these caps have a more spectacular failer mode, sometimes you will get a loud bang and lots of smoke when they explode (quite literally!). Although it seems like a fatal failer when it happens all that needs to be done is to replace the failed filter cap
 
Last edited:
Huh, so this is where the rest of the interesting stuff of MacRumors are! I was only looking at the PPC forum.

If it's one of those GFCI-like breakers (that detects current leakage) you probably have a leak. If it's a simple one (just breaks when too much current used) then you have some other problem.
 
Im down in Waterford.....got my first TAM 2 weeks ago in Dublin!.
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I have a decent collection of macs at this stage and to be honest I would never leave any of these machines plugged in all the time.
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I recap macs all the time and I have seen some crazy stuff over the years. I have plugged in machines and had really bad crackling sounds come from macs before I even turned on the machine
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you could end up burning your house to the ground
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just have one plug for the lot and always plug it out when your not there.
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only way to find the one causing the trouble is to plug just 1 in for a few days...se if it trips
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over and over until you find the culprit
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id have a look at the power supply in the apple ii first. They have those clear plastic paper wound caps that I have seen explode.........inches from my face!
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easy fix
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good luck
 
This a bit of a blast from the past, but I think it's good to resolve all threads where possible, even old ones.

I found the culprit. After much rewriting of the layout of my extension leads, I found that the lead connected to the wall (which has the burden of everything on it) had a really small wattage limit.

Also, it was going from:
Wall -> x4 sockets -> x2 sockets -> x5 sockets.

Really just bad planning. The collection had grown over time so I didn't notice.

It now goes:
Wall -> x6 sockets -> x4 sockets -> x2 sockets.

I can now plug everything in at the same time, on or off. Just goes to show that it's usually something simple. So make sure you have a high wattage cap on your extension leads guys and get smaller down the chain. Use a calculator if you really want to be safe!
 
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