Ground wire on kitchen sink

[maj. tom]

So I have noticed that in metal sink installations there is a ground wire attached to them somewhere. I understand that this is for safety in case somewhere along the line a hot wire touches the supply line... in metal pipes like in USA/Canada. But since we have PVC everything here, is there any use for the ground wire to the kitchen sink? If a hot wire touches a pvc connection it would just melt the pipe right?

What's the standard for TT? And what's the purpose? Also there is no hot water connection to the kitchen sink, so i can't figure it out, but then there's no ground wire on the bathroom sink. Why is the ground wire needed? Where should it be attached, the sink or the pipe? Why isn't there any on other household sink connections?

Please explain plumbers and electricians.

[SMc]

I tort it was grounded in case lightning strike- I coulda dream that though : (

[hong kong phooey]

I tort it was grounded in case lightning strike- I coulda dream that though : (

yeah lightning strikes can conduct through the metal pipes, ad to the kitchen tap so they grounded it in those days, to prevent the most expensive household appliance from getting shock, wile washing the dishes. Also static electricity which is also possible due to water flow .

[gamefreak12]

Could be incase of any electrical kitchen appliances that have a leakage of current and is making contact with your metal kitchen sink

[airuma]

So I have noticed that in metal sink installations there is a ground wire attached to them somewhere. I understand that this is for safety in case somewhere along the line a hot wire touches the supply line... in metal pipes like in USA/Canada. But since we have PVC everything here, is there any use for the ground wire to the kitchen sink? If a hot wire touches a pvc connection it would just melt the pipe right?

What's the standard for TT? And what's the purpose? Also there is no hot water connection to the kitchen sink, so i can't figure it out, but then there's no ground wire on the bathroom sink. Why is the ground wire needed? Where should it be attached, the sink or the pipe? Why isn't there any on other household sink connections?

Please explain plumbers and electricians.

You're smarter than most, if not all of the electricians in T&T..... if you think a little bit you will figure it out. Basically all grounding aims to prevent electric shock (could be 5v) and the bathroom sink is not metal and the pipes are PVC but water is a conductor. BTW, I am not an electrician.

[88sins]

So I have noticed that in metal sink installations there is a ground wire attached to them somewhere. I understand that this is for safety in case somewhere along the line a hot wire touches the supply line... in metal pipes like in USA/Canada. But since we have PVC everything here, is there any use for the ground wire to the kitchen sink? If a hot wire touches a pvc connection it would just melt the pipe right?

What's the standard for TT? And what's the purpose? Also there is no hot water connection to the kitchen sink, so i can't figure it out, but then there's no ground wire on the bathroom sink. Why is the ground wire needed? Where should it be attached, the sink or the pipe? Why isn't there any on other household sink connections?

Please explain plumbers and electricians.

I'll give you part of it, is too much to type
First off think of the entire foundation of your house as one big ground/earth connection.
Secondly, understand that electricity can and does get conducted through almost everything, including concrete, mortar, paint, even (to a far lesser degree) wood, PVC & plastic. Rainy weather, splashes, etc. all leave moisture in concrete and mortar, and moisture conducts electricity.
The reason for grounding the sink ensures that if there is a live current at the metal sink from current leaking through the wires and/or walls of your home, & that current is looking for a ground, it has the grounding wire to discharge itself through instead of the next best thing, which would be your body. Particularly, if there are electrical outlets close to the sink, moisture can get into these outlets. If there is dust creating contact points to live lines in those outlets & that dust transmits current from the wire in the outlet to the wall, that current can travel via the moisture in the wall and dust the paint and mortar to your sink, that will then pass it through you, and if you are barefoot, straight through you to your feet on to the giant ground/earth, which is your floor/foundation.

[maj. tom]

I've done some internet digging. The metal sink should still be grounded even though there are no metal pipes because running water through PVC can create a massive buildup of static electricity. Electrons will freely jump from the PVC to you through the excellent stainless steel conductor of the sink. Which can be mildly unpleasant to very dangerous when you touch any metal part of the sink, especially while wearing certain types of clothes and shoes. So there are many reported cases of people getting a static electrical shock that way.

Beware of Static Electricity Generated by Flowing Liquids
https://www.shimadzu.com/an/hplc/suppor ... 14lab.html

It's unlikely that the sink is grounded for the electrical current leakage from kitchen appliances because all plugs within 6 feet from a sink must be GFCI in the first place, stated in the US National Electric Code, which is what I assume we use in TT also.

Some good to know stuff I guess. Thank you for the replies to my curiosity.

[nick639v2]

On all our restaurant applications we use the grounding regardless of the location. we've had cases locally in high traffic areas near a sink where people get a little zap or when silverware is placed on the wash sink theres a little spark sound...

Simple preparation tables where they use flour and grains, after workload and cleaning you can feel the Lil hair raising static on the surface. Simple rubber footing solved this but it goes to show how easily charges may occur..

[ronsin1]

The TT regulations require you to ground metal sinks. Does not matter how far away the electrical supply is

[Gladiator]

If mama drop the hand mixer in the sink with water she go get shock boy.... you hadda put a grong in the sink so the breaker go trip.

[nervewrecker]

Something I am having a hard time understanding and its best I ask here one time:

When you on the ground and you touch a conductor that is carrying current to ground you can get shocked. Arent, you at the same potential to ground and your internal resistance is more than that of the conductor? I understand you wont get the full dose but if you hold a current wire and not touching the ground you don't get shocked. Same way birds dont get shocked.

[FordeG]

Something I am having a hard time understanding and its best I ask here one time:

When you on the ground and you touch a conductor that is carrying current to ground you can get shocked. Arent, you at the same potential to ground and your internal resistance is more than that of the conductor? I understand you wont get the full dose but if you hold a current wire and not touching the ground you don't get shocked. Same way birds dont get shocked.

Electricity takes the path of least resistance, you often are not that path. Grounding as much things as possible is far safer than not because there is an alternative easier path.

If there is no path, like you mentioned with birds. Your potential becomes high but no electricity flows through you.

What I never understood was how grounding in planes work with regards to lightening.

[gamefreak12]

Lmao

[maj. tom]

Something I am having a hard time understanding and its best I ask here one time:

When you on the ground and you touch a conductor that is carrying current to ground you can get shocked. Arent, you at the same potential to ground and your internal resistance is more than that of the conductor? I understand you wont get the full dose but if you hold a current wire and not touching the ground you don't get shocked. Same way birds dont get shocked.

Well you're right, as far as I understand it also.

If you touch a ground wire that's carrying current to the ground you can get a shock if you are in direct uninsulated contact (barefoot) with the ground. Some amount of current will flow through you and the ground if you are barefoot because you are creating an electrical potential difference between two points. When you are in contact with the ground barefoot you are not really grounded at the same potential as the ground because you are mostly made of water and that creates resistance and thus a potential difference in the circuit. Most of the current will continue to flow in the ground wire. But it only takes 0.1 A flowing across the heart's sinus node to cause atrial fibrillation and a heart attack. If you're wearing proper insulated work boots it should not happen. Always check that your boots are not penetrated by a nail or anything metal. Also there's a standard in the depth they use for ground rods for a reason. http://www.cpuc.ca.gov/gos/GO95/go_95_rule_59_4.html

Current can only flow when there is an electrical potential difference between two points. A bird can't get shocked because all the touching points are the same voltage. If the bird's wing touched another wire while sitting on the bottom wire, it will fry. Because potential difference.

Grounding really means equalizing the voltage across two points. You ever saw videos of helicopter linemen grounding off by attaching the wire to the helicopter first? They're equalizing the voltage across those two points, so now the lineman has no potential difference between him and the wire.

An airplane has static wicks/pins attached all over points on the body and wings that discharges any buildup of electricity that occurs due to lightning or just due to a metal object moving through a magnetic field. The fuselage is designed to act as a Faraday cage to protect everything inside. After a lightning strike they will ground the plane and go over every system with a fine tooth comb before allowing it to fly again.

I never really studied the topic as I'm not an electrical engineer, so disclaimers on that, and willing to be corrected by those who know better.

[ronsin1]

Nerve yuh give me a headache there yes

But it also shows that when you dont practice something you forget it.

Everything you said makes sense however the resistance of your body is higher than grounding wire. As such you should not get shocked

The ground and Neutral are 0 voltage lines and in theory the potential difference between them should be 0 and the PD between the ground wire and any surface should also be 0
Hence if current is flowing through the ground to earth you will not be shocked unless there is a broken wire along the way.

That's all I could rememver I need to go back to the books last time I actually practiced electrical was over 15 years ago

[sMASH]

When u watch lightening strike, or water flow, they take the pathS of least resistance.
Like parralel resistors; the current isn't limited to only the lowest restive resistor, it passes through all the resistors, only at varying currents.

[mragoobir]

If mama drop the hand mixer in the sink with water she go get shock boy.... you hadda put a grong in the sink so the breaker go trip.

Or vibrator

[nervewrecker]

I still having a hard time wrapping my mind around it.

[hong kong phooey]

Something I am having a hard time understanding and its best I ask here one time:

When you on the ground and you touch a conductor that is carrying current to ground you can get shocked. and your internal resistance is more than that of the conductor? I understand you wont get the full dose but if you hold a current wire and not touching the ground you don't get shocked. Same way birds dont get shocked.

Well you're right, as far as I understand it also.

If you touch a ground wire that's carrying current to the ground you can get a shock if you are in direct uninsulated contact (barefoot) with the ground. Some amount of current will flow through you and the ground if you are barefoot because you are creating an electrical potential difference between two points. When you are in contact with the ground barefoot you are not really grounded at the same potential as the ground because you are mostly made of water and that creates resistance and thus a potential difference in the circuit. Most of the current will continue to flow in the ground wire. But it only takes 0.1 A flowing across the heart's sinus node to cause atrial fibrillation and a heart attack. If you're wearing proper insulated work boots it should not happen. Always check that your boots are not penetrated by a nail or anything metal. Also there's a standard in the depth they use for ground rods for a reason. http://www.cpuc.ca.gov/gos/GO95/go_95_rule_59_4.html

Current can only flow when there is an electrical potential difference between two points. A bird can't get shocked because all the touching points are the same voltage. If the bird's wing touched another wire while sitting on the bottom wire, it will fry. Because potential difference.

Grounding really means equalizing the voltage across two points. You ever saw videos of helicopter linemen grounding off by attaching the wire to the helicopter first? They're equalizing the voltage across those two points, so now the lineman has no potential difference between him and the wire.

An airplane has static wicks/pins attached all over points on the body and wings that discharges any buildup of electricity that occurs due to lightning or just due to a metal object moving through a magnetic field. The fuselage is designed to act as a Faraday cage to protect everything inside. After a lightning strike they will ground the plane and go over every system with a fine tooth comb before allowing it to fly again.

I never really studied the topic as I'm not an electrical engineer, so disclaimers on that, and willing to be corrected by those who know better.

Majtom you are right .
Nerve next time you in the tool kit, put your meter on ohms and touch both leads with each hand . try it with your hands dry and with your hands sweaty.
our body has resistance , depending on where you touch the live wire and what part of your body is touching the ground will affect who badly you get shock .

As maj. tom stated Voltage does not kill you, it is current, it messes with your heart . between (i think) 100mA and 200mA(cannot remember the figures you can look it it) it causes the heart to act like a woman
above 200 mA it basically stops the heart but this is better because cpr can revive it , or it could ketch itself. but you will get burned
below 100mA you get the tingle and you tell yourself what a dumb Fcuk i was.

The helicoptor video is a nice video to watch . you actually see the guys crawling on the high voltage lines to inspect it this is it live . it shows that voltage wont kill , but current flow. as tom mentioned. this is why birds can sit on the wire, but if they touch both wires they will get severly burned/killed
Next time you go in an industry to service an AC. you will notice these mattings infront of switchboards. these are rated matting that actually insulates the person from ground when they are working on the equipment .

Any how to answer your question
a) we discussed the potential above , although at anothere time we will discuss were you get shock matters . if the path does not take the current across the heart what happens?

b) your body resistance is higher than the cable so the current should pass the route of least resistance.
Again a small piece of wire had low resistance but when you start adding distance it affect the resistance. this is why electricians calculate the length of the wire from the equipment to the source and calculate the voltage drop due to this resistance . again this will be discussed later . men waiting to drink now
the second part of this was stated by tom . current flows through all paths , it just flows by different amounts

[nervewrecker]

Starting to catch it now.

I keep thinking that you on the ground and you have same potential of the ground but your body does have resistance so there is a potential difference, you are not at zero potential. I was not taking this part into consideration, that is what I was missing.

Walked up to a pole with an earth fault, water at the pole base was boiling. Is only then it had crossed my mind that if I touch it I will get shocked but how can I get shocked if I at the same potential as the earth? Was not willing to put it to the test so we isolated and I rectified the problem.

Got shocked 3 times today yo. Like wtf
Got a zap from a capacitor
Got another zap from another capacitor by a partner of a tuner named boods and got zapped again because the guy didnt unplug the ac when I said unplug. I think boods get shocked same way last time by the guy and I get shocked by one when I told boods isolate and he didnt hear, I held a compressor terminal and get full volts.
Good times yes, lil shock good for the heart every now and then.

[maj. tom]

aye i read of people getting killed from microwave oven capacitors eh. Capacitors like that can hold charge for days after you unplug them. Things like computer power supplies and stuff need to be grounded and then capacitors discharged before working on them. I imagine larger appliances like refrigerators and ac units have even bigger capacitors. Make/buy a discharge tool and always discharge capacitors. It's just a 1MΩ resistor soldered on a piece of wire to make a closed circuit with the two prongs of the capacitor.

[hong kong phooey]

Nerve , you and playing with the health of your heart.
Electric shock messes with your heart and muscles .
I know you have a meter it only takes 1 minute to test for Voltage, it is a good practice .
never trust any one , breakers can be labeled incorrectly or the guy turning off the breaker can turn off the wrong one.
Once you not in presence of combustible gas , short the capacitor to the AC housing, before touching it.

[ruffneck_12]

aye i read of people getting killed from microwave oven capacitors eh. Capacitors like that can hold charge for days after you unplug them. Things like computer power supplies and stuff need to be grounded and then capacitors discharged before working on them. I imagine larger appliances like refrigerators and ac units have even bigger capacitors. Make/buy a discharge tool and always discharge capacitors. It's just a 1MΩ resistor soldered on a piece of wire to make a closed circuit with the two prongs of the capacitor.

Most microwave capacitors have a built in 1M ohm resistor in it already. Just leave it unplugged for a couple hours and you should be fine.

https://www.digikey.com/en/resources/co ... -discharge



but good advice otherwise with the discharge tool for other stuff. I was playing up with a disposable camera the other day and got a good 330V in my tail dread

[nervewrecker]

One for the techs in here.
3 phase system, red, yellow and blue wires.
The main breaker supplies 2 3 pole breakers for isolators, one for air handler and one for condenser.
Condenser has a double pole contactor supplying split phase induction type fan motor and three phase compressor, blue line hooked up direct with a lug, red and yellow on line side of contactor, red and yellow on load side of the contactor.
Fan works with yellow wire disconnected from load side of the contactor, contactor coil not energised, not closed.
Works only when condensor isolator is turned on.
Leme hear allyuh...

[rspann]

Only man to answer that is Parsotan Airconditioning. Give them a call.

[nervewrecker]

That MC get shocked on that system 3 times today. Had to shut it down for safety concerns. Its in a school, some MC may have touched it and get some volts.

[rspann]

So he fully charged then?

[nervewrecker]

So he fully charged then?

like de flash

[adnj]

One for the techs in here.
3 phase system, red, yellow and blue wires.
The main breaker supplies 2 3 pole breakers for isolators, one for air handler and one for condenser.
Condenser has a double pole contactor supplying split phase induction type fan motor and three phase compressor, blue line hooked up direct with a lug, red and yellow on line side of contactor, red and yellow on load side of the contactor.
Fan works with yellow wire disconnected from load side of the contactor, contactor coil not energised, not closed.
Works only when condensor isolator is turned on.
Leme hear allyuh...

This is a delta with a split-phase neutral, yes?

Can you draw it?

[carluva]

Something I am having a hard time understanding and its best I ask here one time:

When you on the ground and you touch a conductor that is carrying current to ground you can get shocked. Arent, you at the same potential to ground and your internal resistance is more than that of the conductor? I understand you wont get the full dose but if you hold a current wire and not touching the ground you don't get shocked. Same way birds dont get shocked.

Well you're right, as far as I understand it also.

If you touch a ground wire that's carrying current to the ground you can get a shock if you are in direct uninsulated contact (barefoot) with the ground. Some amount of current will flow through you and the ground if you are barefoot because you are creating an electrical potential difference between two points. When you are in contact with the ground barefoot you are not really grounded at the same potential as the ground because you are mostly made of water and that creates resistance and thus a potential difference in the circuit. Most of the current will continue to flow in the ground wire. But it only takes 0.1 A flowing across the heart's sinus node to cause atrial fibrillation and a heart attack. If you're wearing proper insulated work boots it should not happen. Always check that your boots are not penetrated by a nail or anything metal. Also there's a standard in the depth they use for ground rods for a reason. http://www.cpuc.ca.gov/gos/GO95/go_95_rule_59_4.html

Current can only flow when there is an electrical potential difference between two points. A bird can't get shocked because all the touching points are the same voltage. If the bird's wing touched another wire while sitting on the bottom wire, it will fry. Because potential difference.

Grounding really means equalizing the voltage across two points. You ever saw videos of helicopter linemen grounding off by attaching the wire to the helicopter first? They're equalizing the voltage across those two points, so now the lineman has no potential difference between him and the wire.

An airplane has static wicks/pins attached all over points on the body and wings that discharges any buildup of electricity that occurs due to lightning or just due to a metal object moving through a magnetic field. The fuselage is designed to act as a Faraday cage to protect everything inside. After a lightning strike they will ground the plane and go over every system with a fine tooth comb before allowing it to fly again.

I never really studied the topic as I'm not an electrical engineer, so disclaimers on that, and willing to be corrected by those who know better.

So my friend you and some of the other posters have the general gist, but allow me to clarify a few areas which should help younto understand grounds...

Grounding does not mean to equalise voltage. The purpose of grounding is to create the path of least resistance for electricity (ie current) to flow in the event that electricity wants to flow anywhere else but within its intended conductors. When current begins to flow in a ground circuit, a potential difference is created.

Secondly, nerve, let me clarify another area. Current does not normally flow in a ground. Current only flows in a ground when there is a ground fault or in other words a part for current to flow through ground. If you ever come across circuits where there is a current in the ground, you have a ground fault. This is why in a properly wired house, you can handle the ground wire with no worries because there will never be current in the ground. Try handling the live wire and you'll get shocked. You can also handle the neutral of a single circuit and not get shocked because neutral is usually grounded in our homes.

So that's why we have GFCI outlets.... In the event that an item is plugged into a GFCI and that item develops a short, ie, a current flow to ground, the GFCI trips to protect the circuit. These are usually resettable. That's why in wet areas like kitchen and bath, GFCIs are mandatory cause the exposure of using an electrical item close to water causes a lower resistance path to ground, due to the water, and increases the likelihood of a ground fault.