Old house; old wiring; new power supply

[fsh42na]

New member here with a question regarding safety issues with using high- power power supplies in an old house (circa 1948). The original wiring is still there though several years ago, contractors put in a family room in our basement. As part of the construction, they took us from the old fuse box (4x 15a fuses) to "220". We now have a circuit breaker box/board.

I'm a complete idiot when it comes to things electrical, so please excuse the dumb question:

Based on the above info (hopefully semi-sufficient), would it be safe to use one of these newer power supplies for the computer in my bedroom. No rewiring was done here. I considered the Coolermaster 850 but I read it needs 15a by itself. I ended up purchasing an X3 and plan to use in the family room since the wiring there is new. What would be the max amps I could safely use in one of my bedroom outlets? I'm currently using an Enermax 600w ps that draws approx 9.5amps. I would have to use a (quality) surge protector between the outlet and the ps. In addition, I would have a printer and small desk lamp attached to the surge protector.

If the info I provided is totally insufficient, I apologize. I just don't want to burn down my house from overloading my circuits.

thanks for your input.:)

[jonnyGURU]

A power supply only puts out what is asked of it.

Does the outlet have an Earth ground?

[fsh42na]

A power supply only puts out what is asked of it.

Does the outlet have an Earth ground?

Nope, only the new outlets in the addition have grounded outlets.

[jonnyGURU]

Heh... well... THAT is a problem.

It'll work without a ground. I used to run PSU's on my load tester with only hot and neutral hooked up, but I kept getting zapped by the metal case.

[fsh42na]

jonny,

are you saying I'm shouldn't be running a pc at all with this outlet or is it just not the ideal situation? If I short something, shouldn't my circuit breakers protect me and the house?

sorry for the dumb ass question.:o

[jonnyGURU]

The breaker will still trip. Goodness knows I've done it. I just don't like the idea of using the PC without a ground.

[fsh42na]

So, in my case, would it be better to go for a lower amp unit like a 700 watt Thermaltake that uses 10amps or should I just go for a "quality" unit like a Zeus, Silencer or another X3? If it's gonna trip, it's gonna trip- might as well have more power in reserve, right?

Thanks again

[jonnyGURU]

No. Like I said in my first reply: It doesn't matter if you have a 500W unit or a 2000W unit. The PSU is only going to put out what's demanded of it. The 10A, 12A, 15A, etc. that you're seeing is the maximum input current of the PSU. The MAX. So naturally a PSU with a greater input capability (higher output wattage at a lower input voltage) is going to have a larger maximum input current, but it's not going to make any difference when using them on the same PC as that PC is always going to draw the same amount of juice from the wall (give or take a little bit due to difference in efficiency) regardless of the maximum capability of the power supply.

[fsh42na]

thanks, the fog is lifting. I might go for another X3 just because it's bigger and badder:D

thanks again.

[Hawkmielle]

On a different note, I might suggest getting a UPS battery backup system to protect your ungrounded computer equipment.

Any damage that occurs should be limited to your UPS instead of your computer system.

[beavis88]

The breaker will still trip. Goodness knows I've done it. I just don't like the idea of using the PC without a ground.

Totally agree. I spent several years in an apartment without grounded outlets, and shocked myself many times on the case. Definitely tripped the breakers a few times, too. But that will happen with a 15A service for everything outside the kitchen :)

It makes me wonder, what is the effect of those shocks on interior components when there is no path to ground to dissipate those shocks? Seems like it could potentially cause some problems (though I am an electro-noob, to be sure). Damage from electrostatic discharge has always been a big bad wolf when it comes to working on PCs...perhaps this explains a couple of mysterious video card and memory failures while I was living in that apartment? :o

Note that I was able to ground myself on the radiator pipes when making hardware changes, etc, but there was no ground during operation.

[kuhla]

I was worried about my PC too since I don't have a ground in my room (also an old house). So I ended up grounding the outlet that I use on my own. According to my power strip it is properly grounded now so I guess I did the right stuff. These are the parts I used:

Gam-Pak Products Ground Clamp - http://www.acehardware.com/product/index.jsp?productId=1292675

Ace 2-3 Wire Grounding Adapter - http://www.acehardware.com/product/index.jsp?productId=1285936

Ace Ring Terminals - http://www.acehardware.com/product/index.jsp?productId=1285895

Enough 14GA solid wire (its what the salesmen said I should get which was overkill? or not? I dunno) to run from the wall outlet I am using, along the wall, into a hole (in the corner of my room) that goes into the basement where the ground clamp was attached to a copper pipe that goes underground.

[fsh42na]

kuhla,

that is just the info I was looking for.:D It would cost way too much to have someone come in to ground the rest of my sockets, so it would be great to be able to at least ground a few of them.

thanks a bunch

I was worried about my PC too since I don't have a ground in my room (also an old house). So I ended up grounding the outlet that I use on my own. According to my power strip it is properly grounded now so I guess I did the right stuff. These are the parts I used:

Gam-Pak Products Ground Clamp - http://www.acehardware.com/product/index.jsp?productId=1292675

Ace 2-3 Wire Grounding Adapter - http://www.acehardware.com/product/index.jsp?productId=1285936

Ace Ring Terminals - http://www.acehardware.com/product/index.jsp?productId=1285895

Enough 14GA solid wire (its what the salesmen said I should get which was overkill? or not? I dunno) to run from the wall outlet I am using, along the wall, into a hole (in the corner of my room) that goes into the basement where the ground clamp was attached to a copper pipe that goes underground.

[signmeuptoo]

Most room outlets, save in the kitchen usually, are 15 amp circuits with wire that can carry a 15 amp load MAXIMUM. Wire gets warm, heck, it gets red hot when more and more current flows on it. As a former electrician I have seen things that, if I recounted all of my tales to you, would horrify you. If at ALL POSSIBLE, rewire those rooms. Seriously. Some old homes have aluminum wiring, which IMHO and the NEC's opinion is a death trap. I won't go into the long winded reasons why right now.

14 guage wire, for 15 amp service, is fine for 1000 watt power supplies, HOWEVER: What else do you have on THAT branch circuit? You will see heat and voltage drops at every wire termination/outlet along the branch and the further down the branch circuit, the worse, as well. I wouldn't run a computer draining 1000 watts and much more than a modest monitor and lamp in a room. We are now getting to a point where rooms need more than one branch or 12 guage wiring with 20 amp service.

NEVER EVER EVER cheat and use a 20 amp fuse or breaker in a 15 amp socket. My boneheaded roomate does that and it infuriates me because my own life is at stake and this house here is a POS and would go up like a fire cracker in about 3 minutes or less. A wall outlet fire will go from spark/ember to full wall on fire in only a couple or minutes or so. Just be careful.

As far as the wattage of the supply, like he said, a 500 watt supply and a 1000 watt supply use just about the same amount of juice (amps) if they have identical hardware running off of them, that should be common sense to you, if not, definitely take some time reading on electrical/electronics as your life does depend on a good basic understanding of it.

If I sound like I am trying to scare you or anybody here about electrical fires, yes, you are right, I am. I am the son of a fire department captain and a former electrician and also a technician so I have seen many horrors over the course of my nearly 49 years...

Note: As wire gets old it corrodes, adding to resistance, resistance creates heat, which creates more resisitance, which creates yet more heat...

Just be careful and smart. Always use a surge protector or UPS with a breaker built in on it whenever using a computer or home entertainment center and avoid loading that same branch circuit which very much else.

Good luck.

[fsh42na]

Most room outlets, save in the kitchen usually, are 15 amp circuits with wire that can carry a 15 amp load MAXIMUM. Wire gets warm, heck, it gets red hot when more and more current flows on it. As a former electrician I have seen things that, if I recounted all of my tales to you, would horrify you. If at ALL POSSIBLE, rewire those rooms. Seriously. Some old homes have aluminum wiring, which IMHO and the NEC's opinion is a death trap. I won't go into the long winded reasons why right now.

14 guage wire, for 15 amp service, is fine for 1000 watt power supplies, HOWEVER: What else do you have on THAT branch circuit? You will see heat and voltage drops at every wire termination/outlet along the branch and the further down the branch circuit, the worse, as well. I wouldn't run a computer draining 1000 watts and much more than a modest monitor and lamp in a room. We are now getting to a point where rooms need more than one branch or 12 guage wiring with 20 amp service.

NEVER EVER EVER cheat and use a 20 amp fuse or breaker in a 15 amp socket. My boneheaded roomate does that and it infuriates me because my own life is at stake and this house here is a POS and would go up like a fire cracker in about 3 minutes or less. A wall outlet fire will go from spark/ember to full wall on fire in only a couple or minutes or so. Just be careful.

As far as the wattage of the supply, like he said, a 500 watt supply and a 1000 watt supply use just about the same amount of juice (amps) if they have identical hardware running off of them, that should be common sense to you, if not, definitely take some time reading on electrical/electronics as your life does depend on a good basic understanding of it.

If I sound like I am trying to scare you or anybody here about electrical fires, yes, you are right, I am. I am the son of a fire department captain and a former electrician and also a technician so I have seen many horrors over the course of my nearly 49 years...

Note: As wire gets old it corrodes, adding to resistance, resistance creates heat, which creates more resisitance, which creates yet more heat...

Just be careful and smart. Always use a surge protector or UPS with a breaker built in on it whenever using a computer or home entertainment center and avoid loading that same branch circuit which very much else.

Good luck.


Mucho thanks for that input. I think I'm definitely going to ratchet down on my ps upgrade for the bedroom. I might go for one of the Thermaltake Toughpowers that are rated for 10amps max. Then I'm gonna look into what type of $$:eek: it'll take to rewire my most commonly used old outlets.