Only issue is my home has no grounding. Its a fuse box era apartment building with no ground in the outlets and no ground in the box. I cant cut into the wall to run any grounding. I read that a GFCI can be used as a alternative to grounding. What do you guys thank about this? would a GFCI keep me from frying my self or my gear
Yes, a GFCI is the proper solution to wanting to plug in a 3-prong grounding-type device when no ground is present in the device box. This is plainly spelled out in
Article 406 of the US
National Electrical Code, specifically
Article 406.3.
Essentially, when you wish to replace a receptacle that is wired from a 2-wire, non-grounded cable, you have three options. Option one is to replace the receptacle with a new two-prong outlet. These are still produced for replacement purposes in this situation and will be of the polarized type. This obviously doesn't help your situation.
The second solution is to replace the two-prong receptacle with a three-prong GFCI receptacle, provided it has been marked "
No Equipment Ground." In addition, any receptacles downstream from the device box where the GFCI is installed (and properly connected to the output
LOAD terminals) may also optionally be replaced with a 3-prong receptacle, provided they are each marked "
GFCI Protected" in addition to "
No Equipment Ground." This is usually done by replacing the first receptacle on the circuit with the GFCI and then updating all the rest of the outlets on that circuit downstream to the 3-prong type, properly marked. GFCI receptacles sold in Canada and the US should include 12 little stickers in the box, usually shiny silver color, that say "
GFCI Protected" to stick on downstream outlets, where used, and sometimes ones with "
No Equipment Ground" just for this purpose since this is a common issue. Alternatively, instead of a GFCI first receptacle, you can install a GFCI breaker for that circuit and then label the replaced outlets accordingly. GFCI receptacles are usually about 1/5th the cost of a GFCI breaker, though, so that method is rarely chosen.
(Doesn't help you with your fuses, regardless...)
The third method is to add a bonding (code-speak for
grounding...
bonding to ground) wire to the device box. This can mean replacing the 2-wire cable with modern 3-wire cable or simply fishing in a ground wire. The wire must go to a main premise ground that meets current electrical code. Depending on the location and soil type, etc. this means grounding rod(s) and/or the service entrance of the water main if supplied by underground copper, etc. That needs to be determined by your local inspector. Generally if you're going to need to upgrade your bonding your inspector is going to require service equipment updating to current code as well, which is what likely tends to cause building owners to not want to ever update anything. One can always try pleading with your local inspector, of course.
Under no circumstances may you ever use one of those three-prong to two-prong adapters when there is no ground present in the device box. Those are only used where the box and two-prong receptacle are grounded (so the faceplate screw is ground) and the little tab is properly mounted with the faceplate screw. They are silly because in this case you should just replace the 2-prong with a standard 3-prong grounded outlet, since the ground is there.
would a scope measure accurately if connected to a GFCI?
Under most circumstances, yes, though the noise margins may be worse on some measurements due to the lack of grounded shielding. It really depends on what you're measuring but I doubt you'll be looking at anything like tiny RF signals as a beginner. My first oscilliscope, an ancient ~5 MHz tube model, doesn't even have a grounded plug. It still works fine, you just have to remember that you can accidentally enliven the chassis of a floating scope if your GND lead goes somewhere that has a path back to mains.
Isn't your landlord required to install any grounding? It seems rather dangerous to run certain kinds of equipment without any ground at all, like most appliances in the kitchen or bathroom.
No, if it passed electrical code when it was built (which it did), it is not required to be updated unless you are doing renovations and open the wall, in which case it is required to be updated to the standards set out in the current code when work is done. Also, if a receptacle is added to an existing circuit where a receptacle did not exist before, the
new receptacle must be properly grounded and bonded to earth (but you do not necessarily need to re-do the other receptacles on the circuit, unless you're opening walls.)
Give or take if the landlord would be bankrupted by the expense, but a convenient anonymous report to the fire department might be appropriate here.
There is no requirement for it to be updated unless other renovation work is being performed which opens the wall. Then it would need to be updated. Calling anyone isn't going to help, it is a perfectly valid installation.
As for instruments, it works the same as "lifted ground". On the one hand, you may not need an isolation transformer. On the other, you have nowhere for fault currents to go in case you do miswire something.
Nowhere for fault currents to go means you'll be less likely to blow up your scope with careless misplacement of the ground lead.
Seriously though, it is perfectly safe. If the GFCI sees more than 5 mA of current flowing outside the closed loop, it will trip. That is barely enough to feel a slight tingle. This could be a nuisance if you accidentally trip things all the time on the bench (I would personally find a GFCI very annoying on my test bench) but it is completely safe. Apart from the shielding and noise shunting/protection aspects, really the only drawback of not actually having the ground is that a faulty piece of equipment, with an internal fault that causes the chassis to become shorted to line, for example, will not immediately blow the overcurrent fuse. You would have to touch the chassis to something that is actually grounded (perhaps you) and cause the 5 mA of current to flow and trip the GFCI instead.
From a safety standpoint of not zapping yourself, a GFCI is far more important than a good ground.
I'm far from an expert on US law, but wouldn't the right to a habitable home include wiring that's remotely modern and up to code? Just the possibility of liability on his side if anything were to happen to you should be reason for him to act. I don't think Texas is known for its lenient penal system.
As long as it passed inspection when it was installed and has not been improperly altered since, it is perfectly valid. It would be silly to require mandatory upgrades. Where does it end? Everyone has to re-wire their house every four years to stay up to date with the code? Should all dwellings be forced to go back and install arc-fault breakers for any circuit feeding a bedroom? Kitchens be gutted and re-wired for split-duplex where only single-circuit outlets are installed? Not going to happen. That would be silly.
The GFCI is not an alternative to grounding. In fact, having grounding and not GFCI is quite dangerous.
Hyperbole much?
No, GFCI is not the same as grounding. They serve different purposes, though from a safety standpoint there is some overlap. In the US and Canada, a GFCI branch circuit
is a valid way of using three-prong, grounding type equipment on an ungrounded installation. You just need to be aware of the limitations, like lack of grounded equipment shielding, which is why the individual outlets must be properly marked accordingly.
The US and Canada do not have silly RCDs on whole premise wiring. We aren't all dropping like flies from getting electrocuted. Quite the opposite. The current methods have been found to be sufficiently safe. Local GFCI protection is required in potentially damp locations like right beside a kitchen or bathroom sink, outdoor outlets, spas, etc. and I personally believe that is sufficient, though a paranoid person could "upgrade" if they really wanted.
Whole-premise RCD protection would be a nightmare for me, personally.
If you only have one of them, I think it is best to have GFCI.
For not getting zapped? Absolutely.
The GFCI basically measures the current that enters the house on the live line and the current that returns in the neutral. If a difference of, for instance 20mA, is detected, it means that some current is returnig on a non intended way, like form your body to the floor, and it shuts down the power.
Regular branch circuit GFCI outlets in US/Canada are 5 mA trip.
It don't always protect you if you touch the live and the neutral at the same time but gives some protection if you touch only the live wires.
It doesn't give you
ANY protection against touching both at the same time!
If you have grounding and no GFCI, the current on a fault appliance can happily return at high levels on the earth cabling. Such things can easily generate a fire.
Now you're just making stuff up. The ground conductor must be sized to handle the fault current of the live conductors. It would be rather pointless to have a 14ga bond wire on an 0/4 feeder.
Moreover, if you ground yourself for ESD protection and touch a live wire, it can kill you if there is no GFCI.
That's a bit of a stretch...
That is why wrist straps have a 1 meg resistor in them.
If you don't have a GFCI I will recommend to install it ASAP as it can save your life.
Alright, we get it. You like GFCIs and hyperbole.
Got it.
It is quite nasty because some AC current can couple with external metal appliance surfaces and induce current on you below the 20mA GFCI tripping point
Dude, it sounds like you have some faulty appliances. You should check into that.
Do American's not put fuses into anything?
This has nothing to do with fuses...
Every plug is fused in the UK, whether it has an Earth or not.
Yeah, that's because you folks use the strange-to-us method of essentially stiffly connecting the whole house directly to the mains feeders and letting the plugs try to play mediator.
Your system seems insane to us, and our system seems insane to you, but they both work.
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