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fredanna

Wierd Voltage

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fredanna

Hello All

There was a thread somewhere on this forum about weird voltage readings using a volt meter and I cannot go back to reference the outcome for what was finally discovered.

 

We're here now and I am an electronic tech. I know the Phils is 220 vac, BUT when I connect my digital meter to the socket I read 359 volts. The thread mentioned about the VECO or Phils power distribution and the pole transformer. There is no actual ground, you really get two hot wires..................correct?? When a 220 volt device is connected it sees what it needs and operates.

I remember the thread discussed how the person was reading from one contact of the plug to ground and he was seeing even weirder things.

Can anyone familiar with the Phils electrical system explain again........sorry.

 

Also, in our condo,we notice the flourescent lights very gently flash or glow even when turned off............!!!!!!!!! So, my thinking is that the wall switch only turns off one of the two hot wires and there is still a voltage on the lamp causing this???????

 

In the USA the 110 volts is one hot and Neutral which is ground and no voltage whatsoever on that neutral wire.

 

My brain needs edumacation

TNX

 

Fred

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KennyF

I'm glad you posted this because I was about to throw m DVM out as It gave a 360 reading in a 220v socket.

I have no idea why but I guess someone with RP electrical experience will reply.

 

Do you mean your fluro lights glow faintly for a little while or than they continue to glow?

 

KinAC

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Headshot

If you think about what happens when you "float" the neutral (don't properly ground it), you will better understand the electrical system in the Philippines. Supposedly, it is a neutral-phase system, but unfortunately, they don't know what ground is here. Because of that, you can get floating voltages (and voltage on the neutral) when load is put on the line. If the neutral is floated in a three-leg (single phase) system, the voltage in one phase can float up while the other floats down. With a two-leg system, you can get very high voltages on the phase wire (think series street lighting) or voltage on the neutral. In any case, if there is voltage on the neutral, there is no ground. Really, the only thing you can do to protect your stuff from weird voltages here is to drive your own ground and connect the point of attachment for your house. You should check the ground periodically, though, because it may tend to act like a sacrificial anode, since it may be the only good ground on the system.

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KennyF

If you think about what happens when you "float" the neutral (don't properly ground it), you will better understand the electrical system in the Philippines. Supposedly, it is a neutral-phase system, but unfortunately, they don't know what ground is here. Because of that, you can get floating voltages (and voltage on the neutral) when load is put on the line. If the neutral is floated in a three-leg (single phase) system, the voltage in one phase can float up while the other floats down. With a two-leg system, you can get very high voltages on the phase wire (think series street lighting) or voltage on the neutral. In any case, if there is voltage on the neutral, there is no ground. Really, the only thing you can do to protect your stuff from weird voltages here is to drive your own ground and connect the point of attachment for your house. You should check the ground periodically, though, because it may tend to act like a sacrificial anode, since it may be the only good ground on the system.

 

Which in English means.........

 

 

KinAC

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Headshot

Which in English means.........

 

KinAC

Hahaha... If the neutral wire coming to your house isn't grounded (tied to earth), you will get weird voltages. Eventually, it will ruin your electronics. The only way to prevent these weird voltages is to drive a ground rod and connect it to the neutral at your service entrance. The neutral wire is supposed to be at zero volts. Only a good driven ground will ensure that.

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A_Simple_Man

Which in English means.........

 

KinAC

Hahaha... If the neutral wire coming to your house isn't grounded (tied to earth), you will get weird voltages. Eventually, it will ruin your electronics. The only way to prevent these weird voltages is to drive a ground rod and connect it to the neutral at your service entrance. The neutral wire is supposed to be at zero volts. Only a good driven ground will ensure that.

 

Question: Is there any way that doing that will cause some Electricity to 'leak' into the ground while I am still paying for it . . thus driving up my bill?

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Question: Is there any way that doing that will cause some Electricity to 'leak' into the ground while I am still paying for it . . thus driving up my bill?

The ground connection for the neutral should be "upstream" from your meter. In other words, it isn't on the metered side. So...no.

 

Putting the ground "downstream" of the meter isn't a good idea, since if there is a problem on the VECO line, it could cause a fault in your house wiring, and thus burn your house down. In the US, utilities won't connect a house that doesn't have a driven ground at the connection point, but that doesn't seem to be a concern here since grounds are so rare.

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KennyF

If the neutral wire coming to your house isn't grounded (tied to earth), you will get weird voltages. Eventually, it will ruin your electronics. The only way to prevent these weird voltages is to drive a ground rod and connect it to the neutral at your service entrance. The neutral wire is supposed to be at zero volts. Only a good driven ground will ensure that.

 

I guess this is something I would need an expert to do as I'm electronics (DC low volt), not electrics (AC110 220).

 

But here's a further complication.

Most of the houses in AC have dual plugs side by side. One is 110 two flat pins and the other 220 two round pins.

Most electronic gadgets like phone chargers, cable box and so on seem to work happily on 110.

 

KinAC

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Headshot

I guess this is something I would need an expert to do as I'm electronics (DC low volt), not electrics (AC110 220).

 

But here's a further complication.

Most of the houses in AC have dual plugs side by side. One is 110 two flat pins and the other 220 two round pins.

Most electronic gadgets like phone chargers, cable box and so on seem to work happily on 110.

 

KinAC

I would bet you dollars to doughnuts that both outlets are 220 volt. The flat pin configuration is common here on 220 volt systems. Likely, they are just trying to make it easier for you to plug things in without using adapters, since some things come with the flat pins and others with round pins. Even in the US, you will see that what we refer to as a 120 volt outlet (or switch) is actually rated for 240 volts. They will happily operate at 220 volts. If you plug something in to those outlets that is actually rated for only 120 volts, get ready for the magic smoke to come out of it.

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Paul

If you think about what happens when you "float" the neutral (don't properly ground it), you will better understand the electrical system in the Philippines. Supposedly, it is a neutral-phase system, but unfortunately, they don't know what ground is here. Because of that, you can get floating voltages (and voltage on the neutral) when load is put on the line. If the neutral is floated in a three-leg (single phase) system, the voltage in one phase can float up while the other floats down. With a two-leg system, you can get very high voltages on the phase wire (think series street lighting) or voltage on the neutral. In any case, if there is voltage on the neutral, there is no ground. Really, the only thing you can do to protect your stuff from weird voltages here is to drive your own ground and connect the point of attachment for your house. You should check the ground periodically, though, because it may tend to act like a sacrificial anode, since it may be the only good ground on the system.

 

Which in English means.........

 

 

KinAC

 

Ground your shit yourself. :)

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KennyF

I would bet you dollars to doughnuts that both outlets are 220 volt.

 

Not so sir. I would keep my doughnuts.

The reason for dual voltage in Clark and Angeles is that when the US was here there was a tremendous influx of 110 equipment from the states.

 

On all cover plates......

One socket is flat pin. They are 110v.

One socket is round pin. They are 220v (and sometimes much higher)

All lighting is 220v

 

KinAC

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fredanna

I'm glad you posted this because I was about to throw m DVM out as It gave a 360 reading in a 220v socket.

I have no idea why but I guess someone with RP electrical experience will reply.

 

Do you mean your fluro lights glow faintly for a little while or than they continue to glow?

 

KinAC

 

 

YUP they glow faintly after turned off!!!! Play the "Twilight Zone Theme"!!!!

 

And thank you HEADSHOT for the info. With the "ground" floating like that it might explain why the flourescent lights are glowing faintly. There must be a voltage leakage from the other circuits in the condo. It really doesn't take much to get a flourscent tube to flash or glow.

 

So, in other words I better be dam careful installing a ceiling fan in mama and papa's house. Coz even though the wall switch is off the other wire will still be HOT!!! Nice surprise!!

 

 

I am a Ham radio operator and holding a flourescent tube next to my radio antenna while I am transmitting will cause the dam thing to glow in a weird way!!

 

So, if we should decide to build here, we'll have to take extra care in a properly wired and grounded system or all of my expensive electronics will go up in smoke. I bet electrical storms here takes its toll.

Fred

Edited by fredanna

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daz

I was having problems with my aircon. The technician measured the voltage. I was only getting 180.

 

He told me to invest in an AVR. Automatic Voltage Regulator. It gives a constant output of either 110 or 220.

 

Ever since I bought the AVR, I have been trouble free.

 

Cheers,

 

Daz

 

 

 

I'm glad you posted this because I was about to throw m DVM out as It gave a 360 reading in a 220v socket.

I have no idea why but I guess someone with RP electrical experience will reply.

 

Do you mean your fluro lights glow faintly for a little while or than they continue to glow?

 

KinAC

 

 

YUP they glow faintly after turned off!!!! Play the "Twilight Zone Theme"!!!!

 

And thank you HEADSHOT for the info. With the "ground" floating like that it might explain why the flourescent lights are glowing faintly. There must be a voltage leakage from the other circuits in the condo. It really doesn't take much to get a flourscent tube to flash or glow.

 

So, in other words I better be dam careful installing a ceiling fan in mama and papa's house. Coz even though the wall switch is off the other wire will still be HOT!!! Nice surprise!!

 

 

I am a Ham radio operator and holding a flourescent tube next to my radio antenna while I am transmitting will cause the dam thing to glow in a weird way!!

 

So, if we should decide to build here, we'll have to take extra care in a properly wired and grounded system or all of my expensive electronics will go up in smoke. I bet electrical storms here takes its toll.

Fred

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David_LivinginTalisay

I am not a qualified/certified Electrician. BUT I did do and Electronic Engineering Apprenticeship with the Ministry of Defence (MOD) in the UK @ SRDE (Signals Reseach & Development Establishment).

I know the THEORY of Electronics and Electricity, as well as some experience of having installed electrical wiring and appliances.

NB: In the UK now, it is illegal to do your own Electrical wiring installation or modifications in Kitchens or Bathrooms. For Safety and official Certification, these must be do by registered, certified, and Licensed Electrical Engineers. You ca not sell a house without such Certification these days I am lead to believe. Just a swell I sold my 2 bedroom apartment that I installed an instant Heat Shower Heater, back in 1981. It was safe as it had it's own breaker, with ground, and the copper water pipe was also properly Earth bonded in at least 2 places to different Ground connections. These Ground connection straps, did not have the Certification label (as it was not requires back then).

Anyway, I mention this to show how SERIOUS the UK takes ELECTRICAL GROUNDING of all metal pipes and Appliances that have electrical connections or could com into contact with Electrical connections if a fault occurred. Also in the UK, the use of Earth Leakage Circuit Breakers are commonly used that disconnects the supply if any Earth current detected flowing to Ground/Earth.

Some appliances (like instant hot water heaters), have their own built in Earth Leakage Detector (the one installed in our Shower here in Cebu, has such and the Test function shows it to work. This was installed by the Builders electrician and we had the whole house wired with Earth/Ground Wire, that connects to long metal spikes, driven deep in the ground where water supply enters the house and near the Cess Pit, so the ground usually 'damp' in that area).

 

There are some good Websites thatgive a good explanation about Power Distribution and Earthing:-

 

Here are some from 'Google' on 'Home electrics & ground':-

 

CAUTION: The color codes for wires referred to in this article are for USA only - I haven't a clue as to what the wire color codes for house wiring are in any other countries. Consult your local electrician for information.

 

Here's a basic description of how the electric power gets to your house. Most homes are supplied with a 220 volt service capable of about 200 amps. Some older homes might not be wired that way. They may just have a 110 volt service. The following describes a 220 volt system in the United States.

 

Back at the power generating station electricity is generated by huge turbine generators which are driven by either fossil fuel, nuclear energy or hydro power, like Niagara Falls. The power is generated at very high voltages and sent out over a network of distribution lines. As it gets closer to your house it goes to a sub station where the voltage is lowered and then sent on its way. It finally arrives in your neighborhood and is sent to a transformer where the voltage is lowered to 220 volts. This is what comes into your house and goes to the circuit breaker box.

 

The next section describes a bit of technical mumbo jumbo about sine waves and phase relationships. You can skip it if you aren't interested.

 

Alternating current (AC) is what is delivered to you and is what runs everything in your home. The alternating part means that the voltage changes constantly from zero to plus 110 volts and then back to zero and then to minus 110 volts. This cycle repeats itself 60 times a second thus the description of your service is 110VAC 60Hz. The Hz is the abbreviation for Hertz, a famous scientist from Germany who also invented the rental car business (and as a sideline invented radio and wireless communications along with a lot of his co-workers, Avis, Enterprise and Alamo).

 

The cyclic variation of the voltage occurs very smoothly and is described as sinusoidal variation, named after Samuel Sinus, a famous mathematician and nose doctor. Now this is important - the 220 volts comes to you in a kinda weird way.
There are three wires coming to your house
. The
one
in the middle (so ta speak)
is called the common.
On each side of that wire are
110 volt wires - 110 volts is measured between that wire and the common
. If you
measure across the two outside wires you will get 220 volts
. It all happens in the complex vector math of the two 110 volt sinusoidal waveforms, but suffice it to say that it works and you get your choice of 110 or 220 volts to run your appliances.

 

Remember the middle wire I called
"common"? It comes all the way from the power generating station as the common wire and it also is attached to the cold water pipe that comes into your house through the ground
. It's important because you should realize that
the earth is part of a circuit of our power distribution system
. What it really means to you is that you can get zapped if you happen to be in contact with some form of ground, be it a kitchen sink or a puddle of water on the ground outside, and come in contact with a "hot" wire. Ground is ground and if you touch a "hot" wire and are grounded elsewhere on your body, current will flow through the circuit. If one of your fingers is in a light socket and another finger on the same hand touches ground, you will feel a shock across your hand. If no other part of your body is grounded that's all that will happen. It will scare you but it won't hurt you or kill you. Well, it might hurt you if you yank your hand away fast and hit it on the corner of the kitchen cabinet or any other relatively sharp object!

 

Confused yet? Well here is one more thing to contemplate. There is
one more wire traveling through your house
. It is sometimes
covered with green insulation and sometimes it is a bare wire buried inside the plastic insulation
of the Romex.
It is a ground wire and is connected to the grounding buss inside your electrical box.
It is
connected to the same place that the white or common wire is connected
but is
used ONLY for grounding of circuits for safety reasons
. Don't think you are smart and try to use that green wire to carry current in a circuit! It is unsafe and ILLEGAL.

 

 

The reason for doing a copy and paste extract from that website http://www.misterfixit.com/hotnot.htm is to show how 110v ac and 220V ac would 'normally' be delivered to a home in the USA.

But here in the Philippines it is NOT done like that!

 

The 'common' wire from the Power Station Generator is NOT delivered to your home (certainly not my home,and most if not all others) - just 2 x Live 'Hot' wires

In our house we do have one more wire traveling through your house. It is a ground wire and is connected to the grounding buss inside our electrical box. It is connected to the Ground Earth spike that we ourselves had installed. It is used ONLY for grounding of circuits for safety reasons.

 

Since there is no COMMON or NEUTRAL wire delivered by the (VECO in our case), there are no other wires connected to this 'GROUND' Earth wire connections.

NB: Do NOT try connecting either of the 2 x Power Wires, entering your house to any Ground connection!

 

Ohm's law
states that the
through a conductor between two points is directly
to the
or
across the two points, and inversely proportional to the
between them.

The mathematical equation that describes this relationship is:

 

f9ae53a99f2b2b6a74146fb04fb3ff73.png

where
V
is the potential difference measured
across
the resistance in units of
;
I
is the current through the resistance in units of
and
R
is the
of the conductor in units of
. More specifically, Ohm's law states that the
R
in this relation is constant, independent of the current.

 

Watts (W) = Volts (V) x Amps (I)

Volts (V) = Current (I) x Resistance ®

After I had that Ground Spike/Earthing Rod installed deep into moist ground, and I measured the AC Voltage from that Ground to one of the 2 x VECO Power supply leads entering the house and connecting to the mains Fuse distribution Cabinet in our house (before we extended with new wiring installed), I measured about 30V ac to ground, so was NOT a Common or Neutral supply feed. Neither was it 110- 120V either. The other wire of the VECO Power feed was then measures to Ground. It again did not read 1120-120V ac, but instead a higher 200V ac to ground. Measuring the Voltage across just the 2 x VECO Power feed wires, gave a reading of about 230V ac

Any attempt to GROUND that 1st power lead to ground connection would mean current flow to ground (same with the other Power lead, but even more dangerous).

Voltage means Current flow and the Electrical Resistance to ground determines how much Current flows.

From Ohms Law: Current (I) = Voltage (I) / Resistance ®, so 30 Volts ac connected to Ground (with not a perfect 0 Ohms connection, say 5 Ohms Resistance) = 6A current flow!

Watts = VI = 30 x 6 = 180W. That wire is going to get warm and add to your electric bill, as well as the potential electrical safety problem, should the connection to the earth rod get broken, as then all the Earth wiring would be carrying 30V ac.

This is why the UK is so particular when it comes to multiple Earth Bonding of any and all electrical wiring in places where there is water - ie Bathrooms and Kitchens, because that current from a faulty earth, if flowing through you to ground via water, may well KILL YOU!

http://www.osha.gov/SLTC/etools/construction/electrical_incidents/eleccurrent.html

50-150 mAExtreme pain, respiratory arrest, severe muscular contractions. Individual cannot let go. Death is possible.

1000-4300 mAVentricular fibrillation (the rhythmic pumping action of the heart ceases.) Muscular contraction and nerve damage occur. Death is most likely.

See that it is possible to die with just 150mA.

During my MOD Apprenticeship, I heard of a 'squaddie' who wanted to measure his body resistance, with an 'AVO' (electrical multimeter). He put the two 'probes' of the 'AVO' Meter on the thumbs of each hand. He noticed the harder he pressed, the lower his body resistance meter reading went. He pushed a bit two hard and the sharp pointed probes penetrated his skin and started to bleed. His body resistance was a lot lower and so the current increased, flowing arm to arm across his heart, and killed him!

The voltage in such 'AVO' meter is 9V DC. For 150ma of current, that is a body resistance ® = 9 (V) / 0.15 (I amps) = 60 Ohms

I do not know if that is just an Urban Legend, or if a 'squaddie' did die from such AVO Meter, but IF you reduce your body resistance below 60 Ohms OR increase the voltage above 9V, then the current WILL be > than 150mA, that is FACT (Ohms Law).

However for PEOPLE/ANIMALS it is not pure Ohms Law that applies for much higher voltages. The body reacts ( muscle contractions and burns/chars, so the current flow may not remain flowing at same high value?).

It's The Current That Kills

Offhand it would seem that
a shock of 10,000 volts would be more deadly than 100 volts
. But this is
not so
! Individuals have been electrocuted by appliances using o
rdinary house currents of 110 volts
and by
electrical apparatus in industry using as little as 42 volts direct current
. The real measure of shock's intensity
lies in the amount of current (amperes) forced though the body,
and not the voltage.
Any electrical device used on a house wiring circuit can, under certain conditions, transmit a fatal current.

 

While any amount of current over 10 milliamps (0.01 amp) is capable of producing painful to severe shock,
currents between 100 and 200 mA (0.1 to 0.2 amp) are lethal.
Currents
above 200 milliamps (0.2 amp),
while producing s
evere burns and unconsciousness
, do not
usually cause death if the victim is given immediate attention
. Resuscitation, consisting of
artificial respiration, will usually revive the victim.

 

From a practical viewpoint, after a person is knocked out by an electrical shock it is
impossible to tell how much current has passed through the vital organs
of his body.
Artificial respiration must be applied immediately if breathing has stopped
.

 
Read
to learn more.

 

 

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KennyF

You can not sell or rent a premises in Australia that is not fitted with a earth leakage device (and smoke detectors too).

This has been a law for quite some time (at least 5, but maybe as long as 15 years) so given the churn rate of Aussies, most homes now are fitted.

 

KinAC

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David_LivinginTalisay

....

During my MOD Apprenticeship, I heard of a 'squaddie' who wanted to measure his body resistance, with an 'AVO' (electrical multimeter). He put the two 'probes' of the 'AVO' Meter on the thumbs of each hand. He noticed the harder he pressed, the lower his body resistance meter reading went. He pushed a bit two hard and the sharp pointed probes penetrated his skin and started to bleed. His body resistance was a lot lower and so the current increased, flowing arm to arm across his heart, and killed him!

 

The voltage in such 'AVO' meter is 9V DC. For 150ma of current, that is a body resistance

Edited by David_LivinginTalisay

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Alan S

Despite what the internet may say, (and the Darwin awards dont confirm it) I dont believe it.

 

Nevertheless, we are talking about mains electricity, and that can certainly kill.

However, it isnt worth getting paranoid about it.

Speak to most people who spend their life working with it, and most will admit to getting numerous shocks. (I certainly did, up to and including 25kv.)

 

Best avoided though.

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fredanna

OK another entry...............I replaced a suspected low battery in my DVM and lo and behold I am reading 222 AC volts. I was wondering what the battery symbol was in a brand new DVM (cheap) meant. I stuck a 9V from Gaisano and it's reading correctly. The battery will only last 3 weeks LOL

 

Fred...................and "davidlivinginTalisay" we will ahve to meet one day. Probably for a long chat

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Headshot

Not so sir. I would keep my doughnuts. The reason for dual voltage in Clark and Angeles is that when the US was here there was a tremendous influx of 110 equipment from the states.

I keep forgetting you are up near Clark now. I spent enough time around there I should have remembered the step-down transformers. I'm sure you would find the same thing around Subic Bay.

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Woolf

I am pretty sure that one tap on the secodary side of the pole transformer is connected to ground, so

what is going to the house is neutral and 220 volt (hot)

 

 

On the pole with a transformer just outside the house in liloan where I stayed for 3 months, there was a heavy gauge wire running down the pole connected to a grounding rod.

 

Ya if you forget to turn the meter off the battery runs out in no time, when you find out the battery is low is always at the time you need the meter the most

 

edit: primary corrected to secondary. I did mean to write secondary

Edited by Woolf

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Headshot

The 'common' wire from the Power Station Generator is NOT delivered to your home (certainly not my home,and most if not all others) - just two live 'Hot' wires. In our house we do have one more wire traveling through your house. It is a ground wire and is connected to the grounding buss inside our electrical box. It is connected to the Ground Earth spike that we ourselves had installed. It is used ONLY for grounding of circuits for safety reasons.

 

Since there is no COMMON or NEUTRAL wire delivered (by VECO in our case), there are no other wires connected to this 'GROUND' Earth wire connections. Do NOT try connecting either of the two power wires entering your house to any Ground connection

The high voltage system feeding the transformers isn't always the same as the secondary system. You can have two phases feeding a transformer on the primary side and a neutral / phase system on the secondary side. If, as you say, the VECO secondary system has two hot legs rather than a hot leg and a neutral, then indeed you can't ground the neutral (since it doesn't exist). This is really easy to check with a voltmeter by checking the voltage between both legs and ground. Running a third wire (tied to a driven ground rod at the service entrance) on all circuits is still a good idea for safety reasons, but it needs western style outlets (three prong) to do any good. Where did you get your grounded outlets? If I can't find a source here, then I will ship a balikbayan box from the US with UL approved outlets, switches and three-wire Romex wiring in December. Then, I will be able to use decent materials in my home here when I build it. I have been looking all over the place on Cebu for good electrical materials and haven't found ANY here.

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DeezNuz

Despite what the internet may say, (and the Darwin awards dont confirm it) I dont believe it.

 

Nevertheless, we are talking about mains electricity, and that can certainly kill.

However, it isnt worth getting paranoid about it.

Speak to most people who spend their life working with it, and most will admit to getting numerous shocks. (I certainly did, up to and including 25kv.)

 

Best avoided though.

 

When I was a kid, I accidentally pissed on an electric fenced. My nipples hurt for a week.

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David_LivinginTalisay

Despite what the internet may say, (and the Darwin awards dont confirm it) I dont believe it.

 

Nevertheless, we are talking about mains electricity, and that can certainly kill.

However, it isnt worth getting paranoid about it.

Speak to most people who spend their life working with it, and most will admit to getting numerous shocks. (I certainly did, up to and including 25kv.)

 

Best avoided though.

 

You are right not to believe it Alan!

 

When that told me that Story in the 1st Year of my Electronic Engineering Apprenticeship with the UK MOD, in 1972, I should have questioned it and asked if they could give us a copy of the AVO 8 MK II circuit schematic diagram.

 

To help establish if this "Death by 9V Battery?" is Myth or FACT, I searched for information on an AVO Model 8 MK II

http://www.richardsr...co.uk/avo8.html

AVO Model 8 MkII

 

AVO.jpg

 

avo8.jpg

AVO Model8 MkII s/n 105043-360 complete with leather case and leads working

 

This model has a 37.5 uA movement and is housed in a substantial bakelite case and weighs in at 2810 grams. AVO multimeters are renowned for their reliability and robustness, the incorporation of a mechanically operated cut out linked to the meter movement and the two switch range selection system have endeared these meters to generations of electrical and electronic engineers.

 

Inflation!

 

In 1970 the Avometer model 8 Mk4 (a later model than mine) cost

post-198-127843217174_thumb.jpg

Edited by David_LivinginTalisay

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musicman666

i often get little shocks from various bits of equipment.. especially when i am not wearing shoes!.. i acctually wired up some of the gear to the outside spike to save me any more shocks and it has worked but now im wondering if i am running up a huge ground to earth veco bill??

 

i have read this thread and all i can say is wtf is going on with the electrical standards here!

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David_LivinginTalisay

i often get little shocks from various bits of equipment.. especially when i am not wearing shoes!.. i acctually wired up some of the gear to the outside spike to save me any more shocks and it has worked but now im wondering if i am running up a huge ground to earth veco bill??

 

i have read this thread and all i can say is wtf is going on with the electrical standards here!

 

I think the Electric Wiring Standards in the USA have improved somewhat, since I read somewhere about the introduction of 3 pin outlets and Earth Leakage Circuit Breakers. Will be some time before the Philippines even gets up to the old standard of the USA?

 

How many USA sockets have one 'blade' larger than the other so the plug can only go on one way around? The idea being so that Neutral, OV, connects to the Neutral power feed. OK so with our VECO Power it is not 0V but 30V, but still better to have that connected to the right lead than 200V. There should be no electrical connection from Neutral cable to the metal Chassis of any electrical appliance. There should be a green Earth wire for that (often separate from the 2 pin plug on Refrigerators I have seen in some cases, rather than fit a 3 pin plug and then someone just breaks off the Earth Pin, as they only have 2 pin sockets in their house, and the appliance than has no safety Ground connection).

 

I may well be somewhat biased, but still say the UK Electrical Wiring Standards and Codes, are among the best in the World and one of the few having power plugs with built in FUSE (that should be the right rating for the given appliance connected to it).

 

You can buy these 3 pin USA type outlets, here in the Philippines, as all sockets in our house are such type since I asked for all to be wired with an Earth (although in some places, I have changed them to be 'universal' WonPro type, so UK 13A Plugs can be used, as well as European 2 pin round plugs, USA 3 pin and USA 2 Pin etc).

 

Wonpro Universal Receptacle Map

universal-map.jpg

 

 

qq4afac36e407bcPDU04.JPG

 

 

 

I still see what appears to be 'normal; power outlets in Bathrooms however!

 

In the UK all switches in bathrooms have to be pull cord operated and any power outlets have to be special isolation transformers that limit the current, so no Hair Dryers allowed!

 

I have been in Hotels in the Philippines where they had Hair Dryers in the Bathroom, near the sink - so hope they were connected to a residual-current device (RCD), similar to a Residual Current Circuit Breaker (RCCB)

 

 

Residual-current device

 

From Wikipedia, the free encyclopedia

 

A residual-current device (RCD), similar to a Residual Current Circuit Breaker (RCCB), is an electrical wiring device that disconnects a circuit whenever it detects that the electric current is not balanced between the energized conductor and the return neutral conductor. Such an imbalance is sometimes caused by current leakage through the body of a person who is grounded and accidentally touching the energized part of the circuit. A lethal shock can result from these conditions. RCDs are designed to disconnect quickly enough to mitigate the harm caused by such shocks although they are not intended to provide protection against overload or short-circuit conditions.

 

In the United States and Canada, a residual current device is also known as a ground fault circuit interrupter (GFCI), ground fault interrupter (GFI) or an appliance leakage current interrupter (ALCI). In Australia they are sometimes known as "safety switches" or simply "RCD" and in the United Kingdom they can be referred to as "trips" or "trip switches". They can be found in kitchens, bathrooms, and other places that can be wet.

 

220px-Residual_current_device_2pole.jpg

 

 

 

Rules and regulations

Rules and regulations differ widely from country to country. In Europe, the UK has only mandated the use of RCDs in new installations since July 2008. In contrast, Germany requires the use of RCDs on all sockets up to 20A which are for general use. This rule was introduced in June 2007 (DIN VDE 0100-410 Nr. 411.3.3). In Norway, it has been required in all new homes since 2002, and on all new sockets since 2006. In the U.S., the National Electrical Code requires GFCIs for underwater swimming pool lights (1968); construction sites (1974); bathrooms and outdoor areas (1975); garages (1978); near hot tubs or spas (1981); hotel bathrooms (1984); kitchen counter receptacles (1987, revised 1996 and specifically excluding the refrigerator outlet, which is usually on a dedicated circuit); crawl spaces and unfinished basements (1990); wet bar sinks (1993); laundry sinks (2005).[1] In Australia, in some states they are required on all power and lighting circuits.[citation needed]

 

 

 

Use and placement

In most countries, not all circuits in a home are protected by RCDs. If a single RCD is installed for an entire electrical installation, any fault will cut all power to the premises. Normal practice in domestic installations in the UK [citation needed] was to use a single RCD for all RCD protected circuits but to have some circuits that are not protected at all (sockets usually are on the RCD; lamp holders usually aren't; other circuits vary by who installed the system). Regulation introduced in 2008 dictate that on all new electrical installations in the UK, all circuits must be protected by an RCD [citation needed]; however, this does not affect existing installations.

 

GFI receptacles in the USA have connections to protect downstream receptacles so that all outlets on a circuit may be protected by one GFI outlet.

 

Residual current and overcurrent protection may be combined in one device for installation into the service panel; this device is known as a GFCI breaker in the US and as an RCBO in Europe. In the US, RCBOs are more expensive than RCD outlets.

 

More than one RCD feeding another is unnecessary, provided they have been wired properly. One exception is the case of a TT earthing system where the earth loop impedance may be high, meaning that a ground fault might not cause sufficient current to trip an ordinary circuit breaker or fuse. In this case a special 100 mA (or greater) trip current time-delayed RCD is installed covering the whole installation and then more sensitive RCDs should be installed downstream of it for sockets and other circuits which are considered high risk.

 

 

 

Testing

RCDs can be tested with the built-in test button to confirm functionality on a regular basis. RCDs if wired improperly may not operate correctly and are generally tested by the installer to verify correct operation. Use of a solenoid voltmeter from live to earth provides an external path and can test the wiring to the RCD. Such a test may be performed on installation of the device and at any "downstream" outlet.

 

 

Limitations

A residual current circuit breaker cannot remove all risk of electric shock or fire. In particular, an RCD alone will not detect overload conditions, phase to neutral short circuits or phase-to-phase short circuits. Over-current protection (fuse or circuit breaker) must be provided. Circuit breakers that combine the functions of an RCD with overcurrent protection respond to both types of fault. These are known as RCBOs, and are available in 1, 2, 3 and 4 pole configurations. RCBOs will typically have separate circuits for detecting current imbalance and for overload current but will have a common interrupting mechanism.

 

An RCD will help to protect against electric shock where current flows through a person from a phase (live / line / hot) to earth. It cannot protect against electric shock where current flows through a person from phase to neutral or phase to phase, for example where a finger touches both live and neutral contacts in a light fitting; a device can not differentiate between current flow through an intended load from flow through a person.

 

Whole installations on a single RCD, common in the UK, are prone to nuisance trips that can cause safety problems with loss of lighting and defrosting of food. RCDs also cause nuisance trips with appliances where earth leakage is common and not a cause of injury or mortality, such as water heaters.

 

A dangerous condition can arise if the neutral wire is broken or switched off before the RCD while its live wire is not interrupted. In this situation the tripping circuitry of the RCD that needs power to be supplied will cease to work. The circuit will look like it is switched off, but if someone touches the live wire thinking that it is de-energized, the RCD will not trip. For this reason circuit breakers must be installed in a way that ensures that the neutral wire is turned off only at the moment when the live wire is also turned off. Separate single-pole circuit breakers must never be used for live and neutral, only two or four pole breakers must be used in cases there is a need for switching off the neutral wire.

 

 

 

Edited by David_LivinginTalisay

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