• Some users have recently had their accounts hijacked. It seems that the now defunct EVGA forums might have compromised your password there and seems many are using the same PW here. We would suggest you UPDATE YOUR PASSWORD and TURN ON 2FA for your account here to further secure it. None of the compromised accounts had 2FA turned on.
    Once you have enabled 2FA, your account will be updated soon to show a badge, letting other members know that you use 2FA to protect your account. This should be beneficial for everyone that uses FSFT.

The Little Red Switch

X

Xegony

n00b
Joined
Aug 30, 2005
Messages
16
Just hypothetically, what would happen if the red switch was changed to 230v in a US outlet while the computer was on? Taking this a little further, say the computer wouldn't turn on after that... Where would the problem lie?
 
Xegony said:
Just hypothetically, what would happen if the red switch was changed to 230v in a US outlet while the computer was on? Taking this a little further, say the computer wouldn't turn on after that... Where would the problem lie?
Click to expand...
"Self Destruct" has been engaged! :p

It would depend on the design & quality of the PSU, but the results could be very unpleasant. :eek:
 
I'll try this tomorrow on one of the old dell pc's at my school tmr :eek:
 
Xegony said:
Just hypothetically, what would happen if the red switch was changed to 230v in a US outlet while the computer was on? Taking this a little further, say the computer wouldn't turn on after that... Where would the problem lie?
Click to expand...

Did magic smoke appear?
 
Spectre said:
Did magic smoke appear?
Click to expand...

Nope... No smoke. No burning smell either. Just tried my old PSU and everything's fine. The other one just won't power on at all.
 
Elmntskater1588 said:
Boom!
Click to expand...

I doubt it. Since you've shown the power supply 120 volts when it was expecting 240, I'd expect it to not power-up.
 
I've had lots of customers do this. Even with cheap-o power supplies. The only thing that's happened is no juice until the PSU is unplugged from the wall, switched back to 110 and then reinstalled.

Your Enermax no worky at all now, eh? Hmm....
 
I tried that once on a flaky machine I was testing, and it borked the PSU to be switched while running. Though switching one to 220v and then turning it on plugged into 110v never hurt anything, it simply just wouldn't run until switched back to 110v.
 
110 V in a 230 V circuit is like having a massive brown-out, so it depends on how well the PSU can take brown-outs, and how long you leave it powered up in this configuration.

Naturally, the other way around (230 V in a 110 V circuit) is a lot more unpleasant.
 
jonnyGURU said:
I've had lots of customers do this. Even with cheap-o power supplies. The only thing that's happened is no juice until the PSU is unplugged from the wall, switched back to 110 and then reinstalled.

Your Enermax no worky at all now, eh? Hmm....
Click to expand...

exactly ;)
its downunder where the fireworks happen :p

http://www.dansdata.com/top686p6.htm

I miss the days when every Power Supply Unit came with a self-destruct switch.

Every normal PC PSU used to have a little slider switch on the back of it, see. The switch was usually red, and it was recessed so you could only slide it with a screwdriver, pen, or unusually long and rigid fingernail. What that switch did - and still does, because many such PSUs are still in service - was switch the PSU between 110 and 220V mode.

If you live in a 110/120V country (ten volts more or less practically never makes a difference; "110V" gear will virtually always work in "120V" countries, unless there's a problem with the AC frequency), then switching your PSU into 220/240V mode (those are similarly compatible voltages) will just stop it from working.

But here in Australia, we now run a nominal EU-standard 230V (it used to be 240V; most Aussies don't even know the standard's changed). In this situation, if you flick the voltage selector switch to the lower setting, there is a more than trivial probability that you'll get a flash, a bang, and some satisfying smoke 'n' stink.

If the PSU's well designed, it ought to just pop a circuit breaker in your fuse box. And if you're exceedingly lucky you'll just blow a fuse in the PSU. But I don't recommend you conduct experiments in this area; there are more entertaining ways to achieve the same results.

You can't do the voltage-switch trick with a lot of modern PSUs anyway, because they're auto-sensing units with the same multi-voltage, 50/60Hz compatibility as many modern lightweight plugpack AC/DC adapters.
Click to expand...
 
It just shouldn't work, but lets say you plug a 110 into a 220 socket, then you would get fireworks.
 
natekoz said:
It just shouldn't work, but lets say you plug a 110 into a 220 socket, then you would get fireworks.
Click to expand...

Way to sum up what ice czar said directly above you several minutes before hand.
 
I just thought I'd take this chance to tell my tell of death and destruction.

Well, while I was doing corporate desktop support, I had some engineers (this is the big red flag) decide that they needed another desktop on the production floor. They hunted and hunted for a 110v outlet, but could not find one within 100 feet of where they wanted the computer, as this was a manufacturing plant where everything was 220v.

Then one of them remembered the little red switch on the power supply of the shiny dell. they spliced a power cable together with a plug that would go into the 220v outlets . . . 15 minutes later they called me and said, "umm, the new computer you guys just sent to us doesn't work." when I get there, I notice the char mark on top of the dell and ask what happened.

After a few "ummm I dunno" answers, I get the real answer. They forgot to change the switch and the power supply failed. Not only did it fail, but it shot a ball of electricity about 6 inched in diameter out the psu exhaust and across the factory floor.

Weeee, I hate engineers.
 
Ok.. wait a minute... They REMEMBERED about the switch. Went through the trouble of MAKING a receptacle for the plug, but then FORGOT to FLIP the switch?!?! OMG!! That's too funny!
 
scalez said:
Not only did it fail, but it shot a ball of electricity about 6 inched in diameter out the psu exhaust and across the factory floor.
Click to expand...

A ball of electricity?

It's a little surprising that a a PSU that which isn't auto-sensing doesn't have a fuse to protect it when connected to a circuit of a higher voltage.
 
i didn't say they were particularly bright engineers . . .

edit

and to mikeblas, i'm not sure if they were even running standard 220 on the floor, or if may have been an actual defective unit that fused together. i couldn't open up the psu case, or dell wouldn't have taken it back, and my manager was hot at the time about the parts budget, otherwise it would be on my wall as a trophy.
 
scalez said:
i didn't say they were particularly bright engineers . . .

edit

and to mikeblas, i'm not sure if they were even running standard 220 on the floor, or if may have been an actual defective unit that fused together. i couldn't open up the psu case, or dell wouldn't have taken it back, and my manager was hot at the time about the parts budget, otherwise it would be on my wall as a trophy.
Click to expand...

The engineers, not being "electrical" in nature (my opinion defered from the incident), probably did the following.

Took phase 1 of said 220V circuit and then Phase 2, then thinking that the factory is also wired with a "neutral", wired in the final Phase 3 as ground. Viola, 720V three phase circuit applied to Dell, hence the ball of electricity. Well in excess of the rated specification.
 
LOL :p

three phase would be very common on a factory floor with any heavy motors
it would also likely be "surge & brownout hell" as well with that type of intermittent load on the local grid
 
You must log in or register to reply here.
Back
Top