the not so glamorus power conditioner

[frob]

first off what is the consensus, are they nessesarry?
my studio is a converted old house (like from the '20s) and redoin all the wiring would be the best option if it where an option. so im in the US so its 110 two prong(thats right not even ground in most of the place) so i should probable have a power conditioner or two in here and thought hay that would be fun why not build one. so any sujestions?

 

[lictme]

First DIY: Get some ground. [Please read PRR's response] and run the ground lines into whatever room your using. tie the ground line to the ground lug of the adapters. You can jump the ground from socket to socket. Works like magic.

*Conditioning note: I live in an old house (albeit, completely rewired) that could really use a second drop from the big service pole outside. I have two APC Line-R 1250VAs (audio and laser printers). They'll work great even when all of our gear is moved in and walls are knocked down and blah, blah, blah. Good stuff.

DIY the fun stuff.

-james

 

[PRR]

> Drive the rod into the ground by your service panel/terminal block and run the ground lines into whatever room your using

Please don't do that.

Power-pole transformer shorts hot to neutral. The neutral rises to 120V, or even 13,000V. In your scenario, it finds Ground by going through your equipment to the dirt-rod. This is very unsafe.

The proper legal way is to ground outlets to the fusebox, and ground the fusebox to dirt. Then most stray power runs directly to dirt, not through your gear or you.

In a house that was wired in the 1920s, there is a good chance that all the wire is run in metal conduit, rigid or flex. In theory, and in old code, that metal conduit is ground. You can install 3-pin outlets and jumper the green screw to a screw or clip on the box. There are even special outlets with grippers on the mounting screws so you can trust the mounting screw to bond to the box (even if the screw is not too tight).

In fact the center screw on outlets is generally considered to "be ground".

In recent code, the fact that flex-conduit is a pretty crummy ground is recognized. In new work, you use new flex with a grounding strap inside, or run an actual groundING conductor back to the fusebox.

But assuming this is not a kitchen or bath, and that this is a small studio, I would simply take one 2-pin outlet through a 2-pin/3-pin adapter (using the ground screw if possible) to several 3-pin power-strips. In most cases, if everything on the system is on the same "ground", it works fine even if that ground is not connected to the rest of the world.

A "power conditioner" is usually something else. It stabilizes wobbly voltage (lights dim and brighten), and diverts spikes to the other side of the line or to ground. If your lights burn steady, and you don't have hash when the elevator or A/C kicks-in, there is not a big need for this. As as describe above, when the really big spikes (power-pole or lighting hits) arrive, often you are in better shape with everything floating than with it in the path to ground.

If you are in kitchen or basement (concrete conducts better than your body), don't fool around with your life. Get a proper legal to-Code ground conductor if at all possible, and also use a GFI shock-preventer (these are legal and effective even where there is bo groundING wire).

 

[lictme]

Of course, you're right PRR.

The last two houses I've lived in we're built before 1930 and there was no conduit (anywhere) so the center screw held the face plate on - that's it. Both houses were rented and I could not rewire.

Cold water pipe (nice, traditional fix) worked well in the first house for ground but I never was never faced with an opportunity to test its security. The second house actually had the ground rod with the wire run. I did have the opportunity to "test" that. Lighting struck very near the house and "charged" the earth (scary stuff)...but, four web servers, various routers and some audio gear were runing off the wired-ground outlets (through UPS) and everything came through the strike without any smoke so, I figured it was safe...definitely not code.

But, after reading your post, it probably had more to do with the UPS than the ground rod and wire-run-from-hell.

-james

 

[frob]

if i where uncomfortable with this type of work i would not have joined this forum. ive done this type of work before. i just no expert, thats also why i am here. the house does have a ground in the kitchen, on a seprate circut would it hurt if i cut in to the ground on that circut? also ive found that the price of UPSs have droped alot would that work insted of the power conditioner? i would prefer to take myself off the circut that i am using as only one circut is grounded, the one with the refigerator and AC hooked to it, now that i think of it ive never blown a fuse, thats kind of odd.

 

[frob]

i ment no offence, thanks.

 

[PRR]

> the voltage in his office at 230VAC! ...neutral wire on an "up-stream" outlet had a loose connection.... If this had been an un-grounded GFI receptacle, there would have been ZERO protection!

(I'm sure you know) GFIs are not made to protect against overvoltage.

They sense difference of current. If 10.010 Amps goes out the black wire, and 10.000 Amps comes back on the white wire, then 0.010A is going "somewhere else". They trip.

But as I understand this case: as far as the GFI can see, there is 10.000A in black and 10.000A in white, no unbalance, no worries. It is not its job to know that the "white" isn't going to feeder CT, but through the coffee-pot to another black 240V away.

Adding a ground to the GFI won't change this.

> The culprit was those cheap "stab in" back wired receptacles

I'm not sure it was ever legal to trust those as a way to split a 120V/240V cable's Neutral. Of course it happened. I see that I can still buy those awful things, though re-labeled. Me, I like to screw. I love "back-hole" when it is a screw-clamp. If it is a tin finger, I always re-terminate on a screw.

 

[PRR]

> Talking about protection with compromised neutrals!

The GFI will still protect against current leaking out of the electrical system into unknown objects (which could be people).

It didn't protect against current running in unexpected paths inside the electrical system. It isn't made to do that. Wall wires and appliances are supposed to take considerable abuse and fail gracefully.

Sharing white wires as a Neutral is a good trick to save a length of copper. But it has to be done WELL. A loose black wire means no power. Same for a non-Neutral white wire. But a white Neutral with unequal loads on the two circuits will tend to double-voltage the low-power side. In a fight between a 100 watt PC and a 1000 watt coffeepot, the PC "wins" with about 210 volts across it.

But even while the PC is smoking its guts out, you could put yourself between either black wire and ground, and (in theory!) the GFI will trip before you get a fatal shock. (In practice, never trust a GFI any more than you look into a loaded shotgun with the safety "on".)

GFI are for people, not the PC and coffeepot.

A GFI will also trip to "protect" an old guitar-amp that has caps from both legs of the line to ground. That is unintended, and probably unfortunate.

 

[PRR]

> this idiot contractor who wired 2 hot legs to the microwave outlet... Fortunately from the same phase, but kind of confusing when you turn off the breaker for the microwave and it keeps on microwaving!

He must have a brother in my town.

My kitchen wires were a mess. Whoever wired it cut off all those annoying green wires. I had to pull-up some more copper from the wall into the boxes and do it right. Now, which breaker kills these outlets?

I plugged in a radio, then flipped breakers one by one until it went off. It didn't go off. Hmmm.... I turned off ALL the breakers, the radio did go off. OK, it wasn't tapped from before the fusebox (like my father's house). Flipping some more, two breakers would turn on the radio. Two circuits came together on one outlet.

In further study: they were 15A wires, that had been foolishly uprated with 20A breakers to meet 1972 Code about kitchen appliance outlets. But what it really was is a 20A+20A=40A breaker capacity, on old wires that were never allowed to carry over 15A for fear of fire.

Of course if they had taken opposite legs, the breakers would have blown instantly. I suspect this arrangement was arrived at trial-and-error, and they probably just stopped wiring when the breakers stayed set.