Hiper 580r

valerian · 27 Apr 2006 at 10:35

hi guys
ive heard it said on these forums a lot that these psus have been returned a lot, one of the reasons being crap fans, fair enough, anyone got any thoughts on replacing fans in psus, i for one would rather replace them prior to a failure which may **** up something else in the system

vanandjuanunited · 27 Apr 2006 at 10:39

I would rather get a new psu myself than play about with the fans. Mainly due to the fact the warranty will be voided and you could end up doing more harm than good.

CurlyWhirly · 27 Apr 2006 at 10:40

valerian said:
anyone got any thoughts on replacing fans in psus, i for one would rather replace them prior to a failure which may **** up something else in the system

I would say that opening up a power supply isn't an advisable thing to do due to them holding their charge for so long.
Apparently there is enough current stored in the capacitors to kill you :eek:

It's not worth the risk IMHO.

valerian · 27 Apr 2006 at 10:51

interesting points, get my mate to do it maybe?

vanandjuanunited · 27 Apr 2006 at 10:53

Take out an insurance policy first.

Cyanide · 27 Apr 2006 at 12:53

CurlyWhirly said:
I would say that opening up a power supply isn't an advisable thing to do due to them holding their charge for so long.
Apparently there is enough current stored in the capacitors to kill you

It's not worth the risk IMHO.

More than enough, it only takes around 0.8amps to kill you. Think of how much is on each rail of a modern PSU.

daven1986 · 27 Apr 2006 at 13:33

my fan hasn't failed yet...........touch wood. but they are very good psus overall. but dont go replacing the fan! just use warrenty to get a new one if it breaks.

SteveOBHave · 27 Apr 2006 at 15:18

Cyanide said:
More than enough, it only takes around 0.8amps to kill you. Think of how much is on each rail of a modern PSU.

LOTS!!!

for a short time anyway. Apparently if you have a (for examples sakes) 12 Volt charge on a PSU then you have a potential 12amp discharge waiting to happen. Of course there are other things to take into account, ie resistance through the skin (if the voltage is high enough it negates this) and also whether you make a good path for current flow - i.e. you are earthed.

Either way, you're foolish to open one up and as likely as not to do yourself a mischief. Also worth noting that if you are not a registered electrician and you stuff it up and your house burns down, you don't get any insurance

(assuming they can prove that is why).

http://www.oz.net/~coilgun/theory/capacitorcharging.htm

fornowagain · 27 Apr 2006 at 17:00

SteveOBHave said:
LOTS!!! for a short time anyway. Apparently if you have a (for examples sakes) 12 Volt charge on a PSU then you have a potential 12amp discharge waiting to happen. ]

By that reasoning everything inside the PC or car lighter socket is dangerous, its all connected to the source. Your not going to die from a 12v discharge, ever put your fingers across a car battery at hundreds of amps? What happens? Nothing. Your bodies electrical resistance is in 1000's of ohms range. Even if you stand in a puddle and tap dance, it's way to high pass anything but mA at low voltage. Btw it only takes 60mA AC to stop your heart, but it needs some voltage to get there. 30Vdc is supposed to be about the lethal limit, 50V starts to tickle a bit.

There is mains AC in a PSU, now that can kill. If you leave the PSU connected to the main socket earthed but switched off any caps will have discharged to the chassis neg after a few seconds. I wouldn't recommend going inside a PSU unless you know what your doing, in case you do some damage. But if you discharge it and unplug, its not going to kill you. And the insurance companies going to take the same view about fire from a home built PC.

ashmanq · 27 Apr 2006 at 17:36

SteveOBHave said:
LOTS!!! for a short time anyway. Apparently if you have a (for examples sakes) 12 Volt charge on a PSU then you have a potential 12amp discharge waiting to happen. Of course there are other things to take into account, ie resistance through the skin (if the voltage is high enough it negates this) and also whether you make a good path for current flow - i.e. you are earthed.

Either way, you're foolish to open one up and as likely as not to do yourself a mischief. Also worth noting that if you are not a registered electrician and you stuff it up and your house burns down, you don't get any insurance (assuming they can prove that is why).

http://www.oz.net/~coilgun/theory/capacitorcharging.htm

wander if being a student of electrical and electronics engineering counts?

fornowagain · 27 Apr 2006 at 17:40

ashmanq said:
wander if being a student of electrical and electronics engineering counts?

God no.

Cyanide · 27 Apr 2006 at 17:59

Well I regularly work with upwards of 33,000 volts and I wouldn't want to touch the insides of a PSU... just in case

fornowagain · 27 Apr 2006 at 19:55

Cyanide said:
Well I regularly work with upwards of 33,000 volts and I wouldn't want to touch the insides of a PSU... just in case

Not live anyway. :eek:

I can up that, try working on HT. Them RF burns are nasty.

SteveOBHave · 27 Apr 2006 at 22:05

fornowagain said:
By that reasoning everything inside the PC or car lighter socket is dangerous, its all connected to the source. Your not going to die from a 12v discharge, ever put your fingers across a car battery at hundreds of amps? What happens? Nothing. Your bodies electrical resistance is in 1000's of ohms range. Even if you stand in a puddle and tap dance, it's way to high pass anything but mA at low voltage. Btw it only takes 60mA AC to stop your heart, but it needs some voltage to get there. 30Vdc is supposed to be about the lethal limit, 50V starts to tickle a bit.

There is mains AC in a PSU, now that can kill. If you leave the PSU connected to the main socket earthed but switched off any caps will have discharged to the chassis neg after a few seconds. I wouldn't recommend going inside a PSU unless you know what your doing, in case you do some damage. But if you discharge it and unplug, its not going to kill you. And the insurance companies going to take the same view about fire from a home built PC.

Yes I am saying that fiddling around inside a "LIVE" PSU or PC is dangerous at the best of times. Certainly sticking your fingers into a lighter socket is not advised.

I agree, putting your finger across a car battery will do squat as it requires a very high voltage to break a human bodies resistance (at which point your bodys resistance drops to about 500 ohms). However if you touch the coil it could tickle

I'm not arguing with you at all, you clearly know your stuff, however I will dispute your statement regarding insurance companies. If you open a home appliance (as I believe a PSU falls under) then you have to be a registered B grade electrician to have any changes as lawful (not sure if that is the right word - but hopefully you know what I mean). (I used to be a registered electrician and also hold a degree in Electrical Engineering - the electrician registration was part of the package in *cough* New Zealand - rules might be different but I believe the NZ laws are based on the UK laws)

Anyways, glad we agree - Don't go into the PSU

The original statement that I was validating was "Apparently there is enough current stored in the capacitors to kill you" which upon investigation is entirely true as demonstrated by the link I posted. The problem arises from the length of time that the current flows, which is negligable and decreases exponentially as a capacitor discharges. So, yes there is enough current to kill you but due to a capacitor not being able to maintain the current for an extended period, and the human bodies large resistance (and the relative low voltage) it doesn't. If the PSU is live, the risk of lights out is drastically increased. I'm sorry I was being deliberately literal in my validating the statement.

Nice to have some intelligent conversation on a forum for once

fornowagain · 27 Apr 2006 at 23:40

SteveOBHave said:
at which point your bodys resistance drops to about 500 ohms

Do you know why? Its because the route taken turns to carbon :eek:

I'm an MEng myself and I've worked on a lot of different types of power units. And the only things that worry me are three phase MW PFC banks (massive charge) and HT circuits. Especially in TV's they can hold a charge for ages and hurt like hell. A little μF/nF cap is not going to hurt you. You can make a nice big paper cloud and bang if you plug a 1F electrolytic capacitor in the mains. A well used apprentice initiation.

My point about the insurance is not if its legal, but that they will consider a PC as a complete apparatus and that any tampering that leads to a fire would be regarded as your own negligence. As for legislation, stuff designated LV (<1000v) its the old BS7671 ‘Requirements for electrical installations. IEE Wiring Regulations. Sixteenth edition’. Its something like "demonstrate competence" so you can change a plug if your trained. And so on with the correct training, its a but vague.

Cyanide · 27 Apr 2006 at 23:47

fornowagain said:
Especially in TV's they can hold a charge for ages and hurt like hell. .

One of our engineers used to do TV repairs for one of the big red stores (can't remember which) and he once touched the wrong thing in a set he hadn't worked on before... got 20kv through him that blew holes in his fingers where he touched it and his knees where it left him and blew him 5 feet across the room.

Morale of the story - don't "think" you know what you're doing and give it a go with electricity. Trial and error just doesn't work!

fornowagain · 27 Apr 2006 at 23:57

Cyanide said:
got 20kv through him that blew holes in his fingers where he touched it and his knees where it left him and blew him 5 feet across the room.

That be the HT coil and sounds live at that, nasty. The worst thing about high tension (mA's) is you get an RF burn which kills the cells around the wound. It doesn't heal for ages like months and the zap is really painful. The buggers can jump a ways and love anything metallic like the frames of your glasses or watch. You soon learn to keep one hand in your pocket.

SteveOBHave · 28 Apr 2006 at 07:39

fornowagain said:
That be the HT coil and sounds live at that, nasty. The worst thing about high tension (mA's) is you get an RF burn which kills the cells around the wound. It doesn't heal for ages like months and the zap is really painful. The buggers can jump a ways and love anything metallic like the frames of your glasses or watch. You soon learn to keep one hand in your pocket.

Yeah, I've heard of people loosing fingers and stuff because the flesh dies. Lots of kids playing on electricity poles as well. One of the worst stories I heard from one of my tutors (spent more time telling stories than tutoring) was of a kid getting baked by a microwave station or something similar... ugh...

Lots of other stories about appliances not being correctly earthed, like a kettle, and it earthing through a baby into the kitchen bench because all the old piping was copper. Talk about scare tactics, I'm still really careful what I do with electronics

SteveOBHave · 28 Apr 2006 at 07:41

Cyanide said:
One of our engineers used to do TV repairs for one of the big red stores (can't remember which) and he once touched the wrong thing in a set he hadn't worked on before... got 20kv through him that blew holes in his fingers where he touched it and his knees where it left him and blew him 5 feet across the room.

Morale of the story - don't "think" you know what you're doing and give it a go with electricity. Trial and error just doesn't work!

TVs are notorius for that. They have a huge bank of capacitors running around the 'system board'. We were told to take a screwdriver and run it over the contacts to discharge them, not sure how safe that is lol...

ashmanq · 28 Apr 2006 at 10:01

SteveOBHave said:
Yeah, I've heard of people loosing fingers and stuff because the flesh dies. Lots of kids playing on electricity poles as well. One of the worst stories I heard from one of my tutors (spent more time telling stories than tutoring) was of a kid getting baked by a microwave station or something similar... ugh...

Lots of other stories about appliances not being correctly earthed, like a kettle, and it earthing through a baby into the kitchen bench because all the old piping was copper. Talk about scare tactics, I'm still really careful what I do with electronics

I am never going near anything with charge again lmao oh wait a minute im doing EEE engineering :eek:

lol