Old house electrical question.

[N80]

I am moving into my grandmother's house. It is over 80 years old. My dad was born and grew up in it.

We are going to have extensive renovations done since it is basically unchanged in 80 years except for AC downstairs.

Anyway, we are going to live in the house for the two months of planning before the work starts. I just noticed today that all of the outlets (there aren't many) have just two prong holes, no ground. What can I do to safely run my computer and a few other appliances that have three prong plugs? This can be a short term solution as we will have them all changed over two three prong outlets during the renovation.

 

[/pine]

Although it is not "to code" in the SE US...I have many times run a single conductor from a grounded water line etc. to an outlet for TV's, computers etc...

 

[captaincrab55]

Although it is not "to code" in the SE US...I have many times run a single conductor from a grounded water line etc. to an outlet for TV's, computers etc...

One should check to see if BX was installed, if so use a tester to check for a ground...

 

[smfcpacfp]

I would just get some 3 into 2 adaptors for the time being for the 3 prong appliances, of course you don't get the benefit of the ground.

I am curious does the house have the old "knob and tube", single stand wiring they used originally when they put electricity in houses. I assume you are going to start from scratch with a new service panel, etc.

 

[studor]

As others have said , I would run a ground for a few critical outlets like computer, printer, microwave and buy a few adaptors. Some old adaptors have a ground wire that can be attached to a ground run from a pipe etc. Living in a house while it is being renovated will be a far greater challenge -- don't ask me how I know (several times over)

 

[captaincrab55]

I would just get some 3 into 2 adaptors for the time being for the 3 prong appliances, of course you don't get the benefit of the ground.

One could install a GFI receptacle & meet NEC requirements in this case.. Keep in mind that you still won't have a ground...

 

[N80]

Thanks for the advice guys, but I'm an electrical idiot.

1)What is the risk of running a few things without the ground?
2) I've seen the two into three adapters with the little ground wire coming off it. I'm assuming I can run a wire to a pipe or whatever. What kind of wire? Bare? Large gauge?

There is knob and tube wiring in the basement but there is also a large modern breaker panel down there as well. I have no idea what this means.

Thanks again.

 

[captaincrab55]

Thanks for the advice guys, but I'm an electrical idiot.

1)What is the risk of running a few things without the ground?
2) I've seen the two into three adapters with the little ground wire coming off it. I'm assuming I can run a wire to a pipe or whatever. What kind of wire? Bare? Large gauge?

There is knob and tube wiring in the basement but there is also a large modern breaker panel down there as well. I have no idea what this means.

Thanks again.

Can you spot us a few pictures of the existing wiring??

 

[mjarrels]

Only 80 years old... thats a new house around here. My old house is civil war era, but has updated electric with the mandated outside cut off. My 11 year old new house doesn't even have that.

mark

 

[/pine]

1)What is the risk of running a few things without the ground?

many electronic devices (especially TVs etc.) are susceptible to power surges that without a way to ground the surge can be damaged...

 

[kenmac]

many electronic devices (especially TVs etc.) are susceptible to power surges that without a way to ground the surge can be damaged...

I agree. You run the risk of frying your electrical appliances without a ground. I 'm not aware of any new equipment that doesn't require a ground. You can buy a tester at the box stores that plug into the outlet and checks ground and polarity. Reversed polarity is also common on an older home where, you don't know who has been running wire

 

[Egon]

Install a new breaker in the main box and have it feed a plug in receptacle in the proper manner. Run an extension cord from the plug in to where ever you want the computer!:thumbsup:

 

[/pine]

What can I do to safely run my computer and a few other appliances that have three prong plugs?

go to a hardware or box store and buy a length of 14 or 12 gauge copper wire also buy a ground clamp made to fit over a water line...buy however many new receptacles required...

as long as your water service is either galvanized or copper, fasten the clamp tightly to any available water line...(an alternative is driving a copper clad rod into the ground)... There will be a place on the clamp to fasten the new ground wire...

I have drilled holes through exterior walls right into the back of receptacle boxes and fished the ground wire this way... whatever is the easiest way to get the wire into the box...

Kill the power to the receptacle you are working on and wire in the new receptacle...be sure to tighten all connections the tighter the better...

you will notice on the new receptacle that one side has bright (silver) screws and one side will be brass or black colored screws...the hot wire (black usually) goes on the brass or colored side... white (neutral) wire goes under the silver screw...fasten the new ground wire to the green lug on the bottom of the new receptacle...

as mentioned you can buy a cheap ($5-$6) a tester that plugs into a receptacle and it will tell you if the outlet is wired correctly...i.e., open ground (your current condition) or reversed hot/neutral etc...

 

[N80]

Thanks guys. Will look into all these options. Moving out tomorrow afternoon and will have no internet for about a week but I'll check back then and let you know how I resolved the problem and/or burned the house down.

 

[orezok]

go to a hardware or box store and buy a length of 14 or 12 gauge copper wire also buy a ground clamp made to fit over a water line...buy however many new receptacles required...

as long as your water service is either galvanized or copper, fasten the clamp tightly to any available water line...(an alternative is driving a copper clad rod into the ground)... There will be a place on the clamp to fasten the new ground wire...

Don't clamp your ground wire to a hot water line. many water heaters have di-electric couplings which may break the ground continuity.

 

[ultrarunner]

I think investing in a APC battery back-up with surge protection will afford much more protection to your electronic equipment than a ground.

Managed a lot of 1920's homes at one time... all had knob and tube wiring and most had either a 30 amp main or two 30 amp main fuses...

One of the tenants required a sophisticated medical device with a dedicated, isolated ground 20 amp receptacle... I had one installed just for that device.

City required the installation of a ground rod and bonding the ground rod, hot and cold water pipes and gas line to provide the ground.

Most of the homes still have 2 prong outlets...

Some of the medical equipment I install for work requires an isolated ground...

In my opinion, you will be fine with a battery back-up surge protector in the short term.

 

[Iplayfarmer]

One could install a GFI receptacle & meet NEC requirements in this case.. Keep in mind that you still won't have a ground...

GFI's are good for "People Safety", but they aren't a good idea for computers, etc. They work by cutting all power to the outlet if a ground fault is detected. That isn't good for a computer, refrigerator, or anything that you really need running.

I've played the trick where I ground one or two outlets for a computer or other sensitive electronics. Now I'm in the middle of doing exactly what the OP said... I'm renovating my entire electrical system. It's a pain, but it's worth it.

 

[captaincrab55]

GFI's are good for "People Safety", but they aren't a good idea for computers, etc. They work by cutting all power to the outlet if a ground fault is detected. That isn't good for a computer, refrigerator, or anything that you really need running.

I've played the trick where I ground one or two outlets for a computer or other sensitive electronics. Now I'm in the middle of doing exactly what the OP said... I'm renovating my entire electrical system. It's a pain, but it's worth it.

Iplayfarmer, What do you think of AFCIs?

 

[hr3]

Do what runner said,,get a cheep ups for the computer.. everything else won't bother in the short term...

 

[/pine]

In my opinion, you will be fine with a battery back-up surge protector in the short term.

there is a reason you will not be able to find any type of (quality) surge protector without a third (ground) prong on the plug...likewise with a back-up battery..

they need the ground to dissipate the surge...

if you read the warranty on just about any surge protector or back-up battery system...it will state that adequite grounding is required...