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mc68k

macrumors 68000
Original poster
Apr 16, 2002
1,996
0
I have a APC UPS that backs up my computer, monitor, and alarm clock. After I bought it, I noticed that it had a grounded plug (three-pronged) and that my wall outlet was two-pronged. So I used an adapter to "convert" the wall jack from 2->3 prongs.

The UPS works fine, but it has a light that stays red and reads "wiring fault". Does anyone know if this is something to worry about? The manual said nothing other than "hire an electrician to convert the outlet".

Thanks.
 
Bascially you're not grounded. I don't know what will happen during a power spike, but it's not really good. Do you live in an old house? The whole house has to be run with a grounding wire.

-Pete

P.S. I run my computer that way.
 
When I moved into my current apartment, I didn't have any grounded plugs where I needed them. I got an electrician to come in and run a new line to the breaker and give me several grounded outlets. I also had him add more phone drops, since there was only one in the kitchen. Before I did that, I also had the ground fault light on my UPS and surge protector. I got a bit nervouse considering how much $$ was invested in my electronics. It was worth it to have the line run.

Unless you are living in a place built in the 1800's, it shouldn't be too difficult (or expensive) to have grounded outlets added. Check into it, have a good electrician (get someone to recommend him/her) come in and give an estimate. Then get at least one or two more to compare before you give the OK on the work.

You will be glad you do this.
 
Stlll confused…

Thanks for the advice guys.

Isn't the UPS essentially a seperate entity from the raw wall electricity? Just seems to me that if the UPS battery is getting charged and the electronics feed directly off the battery at all times, then I'm safe unless something REALLY drastic happens to bypass these safeguards.

I guess my point is, if the battery is getting juice, does it matter how it's getting the juice? The computer runs off the batt and not directly off the wall, so should I really be that concerned about the wall? What does a grounded plug do tha a non-grounded plug can't do?
 
I don't believe that the battery is used unless the power is out. It just continually charges.

-Pete
 
Some one correct me if Im wrong but your missing prong is the one that is wired up to the ground ( the stuff we walk on outside ) and when you plug an appliance in to the wall the outer casing is wired up to the earth prong ( dosn't apply to double insulated appliances which usually have a plastic outer casing) so if for some reason the outer casing becomes electrified the power at the switch board will turn off before you electricute yourself. I hope you get a little of that, Im not to good at explaining things, try www.howstuffworks.com/question110.htm has a better explaination
 
Wow! Thanks Judo, that site really helped.

I looked at APC's website and they had this to say:

"Site wiring fault indicator - Immediately warns you of wiring problems like improper grounds that could cause shocks or prevent the UPS from adequately suppressing surges. (120V units only)"

And the How Stuff Works said this:

"What happens if you cut off the ground prong or use a cheater plug so you can plug a three-prong appliance into a two-prong outlet? Nothing really -- the appliance will still operate. What you have done, however, is disable an important safety feature that protects you from electric shock if a wire comes loose."

So maybe I'll look into that after all...
 
more to it .....

If you don't ground it any spikes in current will have nowhere to go. The UPS uses the ground wire to "dump" excess current.

I cheated and ran a 4 guage wire out a window to a 6' steel rod I pounded 5' of into the ground just beyond the foundation. My Landlady is cheap so this was my best solution. Ironically, it works just fine. I don't have a UPS but I do have an OK surge suppressor with ground-fault indication and it can't tell the difference.:eek: :rolleyes: :cool: ;)
 
To use one of those 3-2 prong adapters, you use the screw that holds the plastic around the outlet onto the wall, but you put it through that metal loop at the top of the adapter.
 
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