What Is A Ground Wire Used For

Eugene is a qualified control/instrumentation engineer Bsc (Eng) and has worked as a developer of electronics & software for SCADA systems.

What Is a Ground Wire?

The hot and neutral cores in a power cable are used to supply current to the appliances in your home. So what about the green wire? Why is it needed? This is known as the "ground" and is an additional wire that is included for the safe of you and your home.

Notation: This commodity was written for a US audience, and so I refer to the protective conductor as "footing". However, it is too chosen "earth" in other countries. Some other deviation is that the term "hot" is used, which is also known as "live". The third departure is that a second hot line is often provided to homes in the The states, resulting in a 240-volt supply (betwixt the two hots) in addition to the 120-volt supply.

What is the ground wire for?

© Eugene Brennan

What Are the Wires in a Power Cablevision?

Hot

This wire is at a potential of 120 volts nominal in the US relative to ground. Current flows out through the hot wire to an appliance. Hot is besides referred to every bit "live" in other countries and voltage tin can be either 110 or 230 volts AC nominal.

Neutral

The neutral wire is at a voltage close to or equal to ground. The current which flows to an apparatus via the hot wire returns via the neutral core in a cable. (See note below).

Basis

This is a protective conductor, included to prevent daze and/or burn down. Footing is also known every bit "globe" in some countries.

The supply from the transformer feeding your abode is split-phase and in the U.S., 2 hots in add-on to a neutral are provided. Lower power appliances are connected betwixt either of the hots and neutral and this gives a 120 volt supply. The voltage betwixt the two hots is 240 volt for supplying higher ability appliances.

Note: The electricity supply in our homes is alternating current (AC). So while nosotros tend to think of current flowing out through the hot wire to an apparatus and returning via the neutral wire, current really flows both ways. So for half of what is known as a "cycle", current flows out through hot and returns via the neutral wire. During the second half cycle, the process is reversed and electric current flows to the appliance via neutral and returns via hot.

AC and DC voltage waveforms. DC voltage is constant over time. AC voltage and current change direction at a rate given by the frequency. This is 60 times per second or 60 Hertz (Hz) in the US. Each repetition of the waveform is called a cycle. — AC and DC voltage waveforms. DC voltage is constant over time. AC voltage and current change management at a charge per unit given by the frequency. This is lx times per 2nd or sixty Hertz (Hz) in the U.s.. Each repetition of the waveform is called a cycle.

© Eugene Brennan

Basis: The Protective Usher

The flex or fixed wiring supplying metallic cased appliances includes a ground usher (colored green in the The states or green/yellow in the EU) in add-on to hot and neutral. Within an appliance, the basis core of the cable is connected to the outer casing of the appliance. The connection may be fabricated either using a spiral terminal or a ring crimp and self-borer screw/commodities. Spade crimps are more often than not non used to prevent a ground from being inadvertently removed instead of hot or neutral and not replaced. Stock-still (e.g. storage heater, kitchen range) and portable i.e corded appliances with extraneous metal which can be touched in normal use must be grounded. Ground acts as a "bypass" for currents in the event of a mistake.

The fault could be due to:

Conductors (eastward.g. wires, terminals, components) at hot or near full mains potential breaking, angle or detaching and touching the casing of an apparatus
Breakup of insulation. For case, insulation on cores of the power flex could become damaged inside an appliance or insulating spacers could become dislodged. As well, metal parts such as screws or nuts which have come undone could bridge the gap between hot and the metal casing
Making contact with a power cable when drilling through a wall

Inside a microwave oven, the ground core of the power flex is connected to the casing using a ring crimp and screw. Note the symbol for ground — Inside a microwave oven, the footing cadre of the power flex is connected to the casing using a ring crimp and spiral. Note the symbol for basis

© Eugene Brennan

What Happens During a Error If an Appliance Isn't Grounded?

If a fault occurs, the external metal of an appliance will become live and the voltage with respect to basis a person is continuing one will exist anything up to 120 volts, depending on which part of the internal circuit touches the casing. If the metal isn't grounded and someone touches the appliance, current will travel through their body to ground.

Coil to Continue

Why Does Current Menstruum to Ground?

The reason why current flows to ground is that the neutral betoken in the supply transformer is connected via a ground conductor to a ground electrode. This raises the potential of the hot usher to about 120 volts with respect to the ground surface. During a fault, or if someone touches a live conductor, current flows through ground conductors and the bulk of the physical basis (i.e the soil) back to the transformer. Isolating rubber transformers, which are sometimes used for powering tools on construction sites, isolate the neutral from ground and then that current cannot flow (or at least very little) if a error occurs. These transformers additionally catechumen voltage to 110 volts in countries where 230 volts is the standard supply voltage. This reduces the current to a safer level if someone experiences a daze between hot and neutral.

For more than information on volts and amps, run into my guide:

Understanding Electricity? What Are Volts, Amps, Watts, Ohms, Ac and DC?

Why Is the Supply Transformer Grounded?

Grounding the neutral of the supply transformer is a safety measure taken to eliminate dangerous rises in potential (greater than the hot voltage) on the hot or neutral conductors entering a home. This could occur for instance if a very high voltage ability line (possibly hundreds of kilovolts) breaks and lands on a "depression" voltage (120 volt) line. Another scenario is the insulation betwixt the principal and secondary of the transformer existence breached. This could allow the master voltage (>10kv) to appear on the secondary. Yet another possibility is a lightning strike on the lines. Static charge can also cause a buildup of voltage on lines.

Basically, grounding the neutral pulls downwards the voltage of the line so that neutral is close to the potential of the earth which we are continuing on and the voltage on either of the hot lines doesn't profoundly exceed 120 volts.

The path of fault current when someone touches a non-grounded faulty appliance (2nd hot in U.S. wiring systems not shown) — The path of mistake current when someone touches a non-grounded faulty appliance (2nd hot in U.S. wiring systems not shown)

© Eugene Brennan

How Does Grounding Solve the Trouble?

Grounding provides a bypass, shunt or shortcut through which electricity tin can period, instead of passing to earth through the person who touches an appliance. Wires chosen equipment grounding conductors (EGC) are run from the electrical panel through the fixed wiring to all socket outlets, stock-still appliances such as ranges or water heaters, light switches and ceiling roses in your habitation. In the case of a portable apparatus, this grounding path continues from the pin in the plug through the flex, to the metallic body of the appliance. At the electrical console, all of these conductors are joined at the principal grounding concluding. A grounding electrode usher (GEC) runs exterior the premises to a grounding electrode embedded in the soil.

When a fault occurs, current flows via the grounding conductor back to the electric panel. If a TNC or TNCS earthing system is in use, all neutrals are joined to ground at the console (or the neutral and ground may exist joined at the output of the supply meter see earthing systems schematic below), and and so the hot to basis fault at the appliance effectively becomes a hot to neutral fault, practically a brusque circuit. A large over-current flows and this trips the MCB (miniature circuit breaker) and perhaps also the GFCI (whichever acts beginning) for the circuit, cut power and making everything safety.

Grounding, all the same, likewise has another important function. Fifty-fifty if the electric current is insufficient to trip a breaker (in the example of a TT grounding arrangement), the neutral usher breaks outside the dwelling house, or devious currents in the neutral cause a dangerous rise in potential, information technology reduces the touch voltage between the casing of the appliance and the expanse on the basis on which the person is standing to a condom level. Both EGCs and the ground rod and the majority impedance from the ground rod to the supply transformer effectively behave as a potential divider. Since the impedance of an EGC and ground rod are a lot less than the equivalent impedance of the soil between the premises and the supply transformer, and since the two impedances are in series, a much smaller voltage is dropped across the EGC than the full supply voltage and so the hazard is reduced.

The low impedance ground conductor shunts current away from the person touching the appliance, reducing the touch voltage to a safe level. (In reality the conductor passes via the plug and flex of the appliance and electrical panel to the ground rod) — The low impedance ground conductor shunts current away from the person touching the appliance, reducing the touch voltage to a safe level. (In reality the conductor passes via the plug and flex of the appliance and electric panel to the ground rod)

© Eugene Brennan

Naming Convention in the USA and UK

Equipment grounding conductors (EGC) = Protective earths (PE) in the UK.

Main grounding terminal = Main earthing terminal in the UK.

Grounding electrode = Earthing electrode in the UK.

Double-Insulated and Not-Grounded Appliances

Appliances such as hair driers, TVs, handheld kitchen appliances, etc. generally have plastic casings. If a fault occurs inside the apparatus (e.m. a wire or component touches the inside of the casing), there is no danger since the plastic body is an insulator. These appliances don't have a footing wire in the flex. Some appliances such equally ability tools are not grounded and instead are "doubly insulated". This means that although the external casing of the tool or appliance may exist metallic, sufficient separation and isolation of the external metal from internal high voltages is effected to forestall electric shock. These devices don't take a ground wire in the cord either.

Double insulated appliances can exist extremely dangerous if they go moisture. This is because the casing is not grounded and can become live if water breaches the separation between live parts and casing. Likewise, the MCB is unlikely to trip and the GFI may not operate either.

Double insulated symbol

© Eugene Brennan

GFCI

A rubber device called a Footing Mistake Circuit Interrupter (GFCI) too known as a Ground Mistake Interrupter or Residual Current Device (RCD) is likely to exist fitted in most modernistic installations. This device monitors the electric current flowing out through the hot conductor and back via neutral. Normally these currents are equal. If current leaks to ground, not all the current returns through the GFCI. Electronics in the device detects this imbalance, and information technology trips out, shutting off the power. The trip current for a GFCI is normally 30mA but can exist college or lower depending on conditions.

A GFCI handles situations such every bit someone touching a alive conductor, such as a damaged power string with exposed cores, or the connector of a kettle left in a pool of water on a sink. (Information technology may too even trip if clammy bread gets stuck in a toaster and touches the element!)

A GFCI also responds to faults as described to a higher place where hot makes contact with the grounded body of an appliance. The device cuts the power if the MCB doesn't "become at that place get-go".

Some other function of the GFCI is to forestall fire. Consider the situation where a damaged and exposed usher makes contact with clammy timber or grounded material, e.thousand. conduit or pipe. This could produce sparks and start a fire if there is any combustible material nearby, e.yard. sawdust, wood shavings or insulation. The current may not be sufficient to trip a breaker, even so, the small leakage current to ground is more probable to be detected past the GFCI, making it trip and shut off the power.

GFCIs can exist installed at the electrical panel, they are available in the grade of a GFCI socket outlet, and you tin besides buy a GFCI adapter that plugs into a socket. An appliance is then plugged into the adapter. This is a worthwhile rubber accessory for an extension lead if yous utilise power tools in the garden.

Three Types of Grounding Systems

TNCS or PME (Protective Multiple Earthing)

This system uses a combined ground/neutral back to the supply transformer. This is then split into separate ground and neutral conductors after the meter. A hot to ground mistake finer becomes a hot to neutral error, and since the impedance dorsum to the transformer is depression, the large, curt circuit current ensures that an MCB for the circuit will trip. The problem with this type of system is that full mains potential could announced on extraneous metalwork of an appliance if the neutral breaks outside the premises. This is why the basis electrode is and then of import. The bulk of the earth between the ground electrode at the premises and the point where the supply transformer is grounded acts like a potential divider.

If someone touches a grounded appliance, the touch voltage betwixt their hand and feet is equal to the voltage between the point at which the electrode enters the basis and their feet. Since this distance is likely to be a fraction of the distance to the supply transformer, the voltage is reduced proportionately. The electricity supply company may install multiple earthing or footing points from the neutral line betwixt transformer and bounds to reduce the consequences and hazard of a broken neutral (especially if they are widely separated)

TNS

The TNS system is often used when a ground can be provided by the armor of the supply cable. If the armor becomes corroded causing bad footing, this organisation can be converted to TNCS.

TT

The TT system is used when the power comes in overhead. The organization uses the majority of the earth equally the render path for error currents. Information technology doesn't have the risk of a cleaved neutral. If a home is distant from the supply transformer, the fault electric current during a hot to ground fault may be insufficient to trip a breaker considering the resistance of the earth is too great. Since the development of GFCIs which can discover small leakage currents to the ground, this is less of an issue. TT systems may be converted to TNCS systems where the ground and neutral are neutralized or joined together at the get out signal of the meter.

Un-Grounded and Grounded Socket Outlets: NEC Regulations

In the U.Due south., both ungrounded and grounded receptacles are used. Ungrounded outlets are prohibited in new buildings just in the situation where an equipment ground conductor is not present, NEC code exceptions allow these to exist replaced by either another non-grounded receptacle, a GFCI receptacle or a grounding type receptacle fed by a GFCI as long as the receptacle is marked "No equipment ground" and "GFCI protected".

2-pivot in-grounded receptacles tin can exist upgraded to three-pin grounded receptacles with the improver of new ground wiring.

Bonding

Metallic services such every bit water and heating pipes and hot water heaters are grounded with a heavy gauge wire routed dorsum to the electric panel. This ensures that if a hot wire makes contact with these services, a big current will flow and trip the billow. The heavy gauge wire is rated so that it tin bear the current which may flow if a hot from a high current circuit makes contact with the service. Too, the heavy judge keeps the resistance of the cable low. This ensures that as electric current flows through this resistance, the resulting voltage rise is kept below safe limits. This is vitally important in bathrooms where everything is damp and nosotros may be in our blank anxiety and making relatively expert electrical contact. Everything such as radiators, water pipes, wall heaters and the drain in the bath/shower are continued together by a bonding conductor. This "equipotential bonding" keeps everything at the aforementioned voltage and there is no difference in voltage betwixt for instance a showerhead and the drain.

Different types of grounding systems. — Unlike types of grounding systems.

© Eugene Brennan

Electric Wiring Color Codes

This Wikipedia article gives lots of info about wiring and color codes used in various countries around the earth.

References

Fish RM, Geddes LA. Conduction of electrical current to and through the man body: a review. Eplasty. 2009;9:e44. Published 2009 Oct 12.

This article is authentic and true to the best of the author's noesis. Content is for advisory or amusement purposes only and does not substitute for personal counsel or professional person advice in business, financial, legal, or technical matters.

Questions & Answers

Question: When an iron pole is moisture, why doesn't the current flow through the water?

Answer: Current volition flow through water, only only if it completes a circuit. The amount of electric current that flows depends on the nature of the water. Deionised or distilled water has few ions, then the electric current volition exist small. Ordinary tap h2o will behave electricity because of dissolved chlorine, aluminum salts used for deflocculation, etc.

Question: I bought a new dishwasher with stainless steel door. The door shocked me. I hired an electrician, who tested the door equally carrying 79 volts. He tightened the footing in my wall which reduced the door's voltage to 47. He tightened the ground in the dishwasher'south junction box. At present it doesn't daze me. I am concerned where the electricity is coming from to get to the dishwasher door. Is making the basis solid hiding a defect in the dishwasher?

Answer: I suggest you get another electrician who can deal with this floating footing situation. The ascent in voltage could be due to whatever appliance with a live to ground fault, and if the electrician disconnects appliances one by i, they may exist able to identify which one is causing the problem. The mistake could also be caused by a live to basis fault in side by side premises and this can exist communicated to side by side buildings via connected water pipes. It would exist interesting to know how the electrician measured the ground voltage. Did he measure the voltage between ground and neutral? Or ground and the ground rod? Is there fifty-fifty a ground rod? Is it working properly? Is it connected? (i of the functions of the rod is to keep the impact voltage down to a safe level).

Question: I put together a treadmill, and at that place is a ground wire with a metal circumvolve on the stop that I'm supposed to put a spiral through to attach to the frame of the treadmill. The trouble is, there's no mode I can get the screw screwed in. Would it exist safe to just tape the ground wire metal role to the metal frame?

Respond: No, you'd need a meliorate, more reliable connectedness than that. You could drill a pigsty, sand off any paint to betrayal metallic and use a self-taping screw with a washer. Alternatively, drill a larger pigsty and utilise a commodities with a nut and spring washer or lock nut.

Question: What is the symbol of ground wire?

Answer: A vertical line with three horizontal lines under it, successively decreasing in width.

Question: Where do I wire the world on an RCD?

Reply: An RCD doesn't have an world (ground) connection. It has an incoming live and neutral pair and an outgoing live and neutral pair. If there'southward a departure between the electric current flowing out the live and the neutral current returning, information technology will trip.

Older manner ELCBs were voltage sensing devices that tripped when they detected dangerous voltages on earthed metalwork. If this voltage exceeded a gear up level wrt a remote reference earthed electrode, the device would trip.

RCDs used to be called current-operated ELCBs which led to confusion, hence the current name.

Question: Why is the voltage between Neutral and Ground more 25VAC in the house we rent at present?

Answer: The neutral and ground may not be connected together in the house. This would be the case if a TT grounding arrangement is used. Also if the house is fed by a cable with metal armor/conduit and there isn't continuity dorsum to the transformer, this could upshot in a difference in potential.

The safest thing to practice is get an electrician to bank check out the situation.

Question: What are the materials for ground World and neutral?

Answer: Diverse materials are used. Copper for conductors, galvanized steel or copper for rods, brass or nickel plated cablevision clamps.

Question: What is white wire?

Answer: It depends on the country. In the US and Canada, white or grey are used for neutral, but in Australia, white is used for phase two in a multiphase system or for "switched active".

In the US, white could likewise be used every bit a switched wire (eastward.k. for lights) and sometimes blackness tape at the ends indicate this. In whatsoever case, earlier someone attempts to modify wiring, they should ensure power is switched off at the breaker panel, plus double bank check with a neon tester that power is definitely off for the circuit.

This Wikipedia guide shows the colours used in each land:

https://en.wikipedia.org/wiki/Electrical_wiring

Question: My ground terminals shows they got voltage, can I go a quick solution?

Answer: The best thing to do is to become an electrician to suss out the situation. Floating grounds can be unsafe if the potential is at a dangerously high level compared to other metal appliances or services within touching distance.

Cal Stowe from Houston, TX on Baronial 12, 2019:

In my outside main breaker console, the neutral bus is connected to:

i) the ground omnibus

2) earth electrode

3) conductor back to the transformer

4) 100 kva surge protector

This console is continued to an inside panel with all the individual breakers.

The plumbing is connected to a separate earth electrode 4 feet away. Should the plumbing globe electrode be continued to the power globe electrode?

If they are separate:

1) Pipage ground fault voltage should be relatively high, current low, and breaker may non trip due to high impedance from piping earth electrode to transformer globe electrode.

2) A high voltage surge would create high potential betwixt connected devices and plumbing faucets, etc. At that place would be no potential plumbing to floor.

3) A lightning ground strike would create some potential between the two earth electrodes, and some potential between plumbing and flooring due to voltage gradient.

4) Surge protector dump to world will induce piffling voltage on plumbing.

If the world electrodes are connected:

1) In the effect of a ground fault, voltage volition be low, and current high through neutral back to transformer. Breaker will trip.

2) A high voltage surge will not raise neutral and plumbing voltage?

3) A lightning ground strike will induce some voltage and electric current between the basis electrodes.

iv) A surge protector dump to earth volition induce some voltage on the plumbing?

Eugene Brennan (author) from Ireland on March 18, 2019:

Howdy Jim, it sounds as though in that location'due south a hot to footing fault somewhere in the appliance. If y'all ground it by replacing the flex and plug, it would still trip a GFCI unless the fault is sorted. Some other scenario with a three cadre grounded string is that you could take a bootleg ground in 1 of your receptacles and if hot and neutral have been reversed, this would place live voltage on the casing of the appliance.

Might be a good thought to take it somewhere and get it checked. I don't give advice online on these matters because something could be missed and there could be an unfortunate effect!

Jim G on March eighteen, 2019:

Hello Eugene

I'm hoping that you can propose. I recently came into possession of an one-time film projector from the 1940's. The projector is primarily made out of metal, has tubes, and a string with no ground prong.

I plugged in the projector and turned information technology in and success the lights came on. But then I noticed a slight tingle when I touched the projector. Luckily I was wearing safety soles. I opened up the projector and could non come across any obvious wire touching the case , etc. I got my multi meter and ran a wire to the business firm ground which is close to my work bench. With my meter connected to the house basis I would read 120v from multiple locations on the projector.

I'1000 basically at my limit of electrical competence. Would replacing the power string with a grounded cord solve my problem and make the projector safety to use.

Thank y'all for your communication.

Jim

Tyrone on September eleven, 2017:

I have to say this is the best article on grounding I have plant on the net. Congratulations.

Eugene Brennan (author) from Ireland on September 11, 2017:

It depends on the grounding system Tyrone. If TT grounding/earthing is used, the majority of the ground may take a big resistance and and then electric current would be lower than that in the neutral in a mistake situation (perchance insufficient to trip an MCB, but when the installation is protected past a GFCI/RCD, this will trip). In a TN-Southward arrangement, a big brusque circuit current will flow back via the separate ground to the supply transformer. In a TN-C system which has a mutual combined neutral/ground back to the transformer and appliance cases connected to neutral, a larger than normal electric current volition flow on this usher during a fault. A cleaved neutral conductor tin cause a dangerous potential on the metalwork of appliances. A TN-CS organisation provides separate ground and neutral to appliances. If in that location's a fault, a large electric current volition flow through the equipment ground (protective earth) dorsum to the panel. This will exist larger than the current flowing in the neutral core of the cable feeding the appliance, but will flow in the neutral conductor dorsum to the transformer.

So information technology's really only TT systems where the resistance is high. The bodily footing wire from the apparatus dorsum to the panel would have a low resistance.

Tyrone on September 11, 2017:

I'm thinking at that place wouldn't exist much current travelling along the ground path because of the much higher resistance compared to the neutral wire?

Eugene Brennan (author) from Ireland on September 11, 2017:

A circuit is normally completed via neutral, but if a hot to ground (live to earth) fault occurs, in that location'south as well a parallel path for current to menstruum through via ground back to the transformer (and also the neutral conductor, if ground is connected to neutral at the panel).

Tyrone on September 11, 2017:

In the event of a fault it seems the circuit is non being completed via ground but via the neutral wire. Therefore the grounding on both the transformer and residence are stand lonely and are only there to bring the neutral down to 0 volts?

Eugene Brennan (author) from Republic of ireland on August 28, 2017:

Hi Izhaan - This link shows the colours of earth wires in electrical installations:

https://en.wikipedia.org/wiki/Electrical_wiring#Co...

Earthing/grounding conductors may have a coloured sheath or be blank without a sheath in fixed wiring cables. The earth conductor in a flexible power cord supplying an appliance normally has an insulating sheath. In socket and lighting outlets and electrical panels, blank earth conductors are provided with a coloured sleeve to insulate them from inadvertent contact with live/hot parts and also to identify the conductors.

If you are considering making any electrical modifications, I highly recommend yous consult a qualified electrician. A elementary mistake can show fatal!

Izhaan on August 28, 2017:

Plz tell me

How can i identify earth wire in household circuit.?

Eugene Brennan (author) from Ireland on May 21, 2017:

....the hair drier's pb/cord/flex that is, not the canis familiaris'due south. (Maybe you should replace the dog besides.. LOL!)

Eugene Brennan (author) from Ireland on May 21, 2017:

Howdy Denise,

Possibly there is invisible impairment, i.e. broken wires, in the flex from the dog stretching information technology. Sometimes if the stranded copper cores in a flex are cleaved, the wires can exist pulled until they snap and the lead then shortened. However the safest thing would exist to completely replace the lead.

Denise field on May 21, 2017:

Give thanks y'all so much Eugene. Youve really put my mind at ease. Unfortunately the lead has been shortened so no exposed wires!! Merely! It worked for almost 1 minute and so stopped. There was no aroma indicating the motor burnet out no no blindside no spark just stopped maybe the plug is old what do you lot retrieve obviously without seeing it. Just glad to know I'm not going to be shocked etc.

Eugene Brennan (author) from Republic of ireland on May nineteen, 2017:

Hi Denise,

If the casing of the hair drier is plastic, it doesn't need to be earthed. I presume you mean the copper of the wires was visible? If there are even so sections of the flex, afterwards the plug was replaced, where the copper wires are exposed , the whole lead needs to be replaced (or possibly shortened if the bad bit is near the plug end).

Denise field on May 19, 2017:

Okay hither goes my hairdryer lead (flex) has been chewed in half and so I gave it to my neighbour (yes I'thousand rubbish!!)

He put on a new plug, the other one was stock-still on the lead. Only said its non earthed it only has 2 wires which were visible cutesy of the canis familiaris!! These visible wires are copper im not going to get electrocuted am I?

Eugene Brennan (author) from Republic of ireland on April 10, 2017:

Hi Ned,

The world wire doesn't behave a unsafe voltage (at to the lowest degree it shouldn't assuming the globe rod is working properly and the touch voltage is below safe levels during a mistake situation).

The roofing on an earth wire is used for identification but can also give the inner core some protection from damage. It also acts equally insulation if for instance the wire feeds into a socket outlet/light fitting. This prevents alive parts/wires inadvertently touching the world conductor when for case socket plates are removed/replaced. Usually however alive wires are insulated and live parts are shrouded, so this doesn't oft happen.

I don't retrieve it's a major event if the cablevision insulation is separate, in any instance the pipes it connects to are uninsulated. I would be more worried that the inner core has been damaged and strands cleaved from the cable being repeatedly bent during installation/maintenance work. Information technology may have but been chaffed when work was washed, but it'southward no harm getting the cablevision checked by a qualified electrician.

Ned Tallyho on April x, 2017:

The greenish/yellow (Eu) cable connecting copper pipes near my gas combi boiler is bent over to fit in merely the bare wire

tin be seen where the cable has split due to being aptitude. Is this dangerous and should I get information technology changed?

Eugene Brennan (author) from Ireland on August 03, 2015:

The older manner NEMA 1 -15 two pole socket was 15 amp rated and un-grounded. It is non permitted in new structure but there are probably lots of these still out in that location. If an apparatus has a metallic casing (eastward.g. a metal kettle), it needs to be grounded. The exception is double insulated appliances which have metallic on their exterior but are not grounded. This is because the metal is separated from the inner workings to the extent that it is highly unlikely to become "live". If a plug isn't moulded onto the flex, you can always check whether the appliance is grounded or non past opening it upwards to see if a green wire is connected to the ground pivot. However this isn't a total guarantee, and I accept come across appliances which were marked equally double insulated and I think should have been grounded, but weren't during manufacture. Many appliances are un-grounded nowadays simply considering of their plastic construction.

Anyway, while a 5 -xv adaptor with the pin removed would fit into a ane - 15 socket, you could stop up forgetting, and plugging an apparatus requiring a basis into it (or someone else not realising the change could exercise so!). Besides five - 15 plugs or adaptors with the footing pin removed are unpolarized. So hot and neutral going to an apparatus could exist reversed if the adapter is inserted upside downwards. This would result in the switch in the apparatus not shutting off ability. And then if anyone does any maintenance on an appliance with the plug still inserted into the wall, (and assumes the switch in the appliance has cut the power) , they could be electrocuted. It can be very dangerous if lamps are wired incorrectly with the hot and neutral reversed because not only does the switch in the cord not cut the power, the outer screwed crush in the ES lamp holder too get live and could possibly be inadvertently touched when screwing in a bulb.

Ideally you should get your sockets upgraded to 3 pin grounded types. I know this can be a real pain because new wiring with a ground conductor would take to be run back to the fuse box, which isn't always possible and can result in unsightly surface wiring if hiding the wiring isn't possible. The side by side all-time alternative is to accept the socket replaced by a 3 pin blazon protected by an integral GFCI.

If anyone'due south interested, this is the link to the Wikipedia folio with details of connectors:

https://en.wikipedia.org/wiki/NEMA_connector

NEC lawmaking 406.four(D)(2) covers replacement of two pin socket outlets

MG Seltzer from Southward Portland, Maine on August 02, 2015:

This topic was only on my mind every bit our GCFI outlet in the bathroom isn't working, which means that the i almost the kitchen door has kicked itself off. I had just been thinking, "I really demand to sympathize how the current flows through the system." Besides, years agone, a constractor told me the grounding plugs on adaptors were "useless," and could be pulled out with pliers to let a three-prong plug fit a standard outlet. And I remember thinking, "Now is this true?" I am bookmarking this Hub because I see lots of good detail that I think volition respond my questions. Voted thumbs upward, of course.

Eugene Brennan (writer) from Ireland on February 22, 2013:

Cheers for the comments! Yes bad or non real grounds or missing earth electrodes can cause all sorts of shocking experiences! Also relying on water pipes for earthing is a bad idea every bit h2o supply regime tin can supercede sections of metal piping with plastic.

Judy Specht from California on Feb 22, 2013:

Then at that place is the electrical systems in old houses that can requite y'all a thrill. Dad was an electrical engineer and hubby was an electronics tech in the Navy. This is a well written hub. Nice work.