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Just got my first generator - need some help
9/25/2011 7:50:44 PM
Yamaha EF2000iS
1600 / 2000 Watts
13.3 / 16.7 Amps
1) Will a 12 gauge 15 amp extension cord (12/3) be OK ?
2) Manual is confusing (for me) as to what oil to use. Am not expecting to use in very cold temperatures. Will I be OK with 10W-40 fully synthetic?
3) Manual talks about grounding the generator if using with a grounded appliance. Huh?
1600 / 2000 Watts
13.3 / 16.7 Amps
1) Will a 12 gauge 15 amp extension cord (12/3) be OK ?
2) Manual is confusing (for me) as to what oil to use. Am not expecting to use in very cold temperatures. Will I be OK with 10W-40 fully synthetic?
3) Manual talks about grounding the generator if using with a grounded appliance. Huh?
9/25/2011 8:00:41 PM
Originally Posted By johnpfw:
Yamaha EF2000iS
1600 / 2000 Watts
13.3 / 16.7 Amps
1) Will a 12 gauge 15 amp extension cord (12/3) be OK ?
Should be fine if you don't use a LONG cord. If it's between 50 and 75 feet, you'll be OK.
2) Manual is confusing (for me) as to what oil to use. Am not expecting to use in very cold temperatures. Will I be OK with 10W-40 fully synthetic?
Probably would be OK. But I would use whatever viscosity they recommend for the extreme temperatures in your area.
3) Manual talks about grounding the generator if using with a grounded appliance. Huh?
The breaker on the generator won't trip if not grounded if your appliance has a short circuit.
Yamaha EF2000iS
1600 / 2000 Watts
13.3 / 16.7 Amps
1) Will a 12 gauge 15 amp extension cord (12/3) be OK ?
Should be fine if you don't use a LONG cord. If it's between 50 and 75 feet, you'll be OK.
2) Manual is confusing (for me) as to what oil to use. Am not expecting to use in very cold temperatures. Will I be OK with 10W-40 fully synthetic?
Probably would be OK. But I would use whatever viscosity they recommend for the extreme temperatures in your area.
3) Manual talks about grounding the generator if using with a grounded appliance. Huh?
The breaker on the generator won't trip if not grounded if your appliance has a short circuit.
9/25/2011 8:07:32 PM
Answers as follows
1. 12 guage is fine, keep it under 75 feet long.
2. Break in the engine first on some regular 10/30 oil (not synthetic), make sure its a name brand oil,
brand does not matter as long as its a good name brand. Then put 10/30 synthetic in the engine, the rings
of the engine will seat in better while breaking in with regular oil. I like 10/30 oil better than 10/40, I feel its a better oil. YMMV
3. Don't worry about grounding the generator, it is already grounded to the appliance it is running when you plug the cord in the generator.
1. 12 guage is fine, keep it under 75 feet long.
2. Break in the engine first on some regular 10/30 oil (not synthetic), make sure its a name brand oil,
brand does not matter as long as its a good name brand. Then put 10/30 synthetic in the engine, the rings
of the engine will seat in better while breaking in with regular oil. I like 10/30 oil better than 10/40, I feel its a better oil. YMMV
3. Don't worry about grounding the generator, it is already grounded to the appliance it is running when you plug the cord in the generator.
9/25/2011 8:16:53 PM
Originally Posted By Rockyriver:
3. Don't worry about grounding the generator, it is already grounded to the appliance it is running when you plug the cord in the generator.
3. Don't worry about grounding the generator, it is already grounded to the appliance it is running when you plug the cord in the generator.
And if the appliance short circuits, how will it cause the breaker on the generator to trip for a ground fault?
9/25/2011 9:52:29 PM
I have a Honda 5000 generator at work I keep in the bed of my truck. It is not bolted down, just secured with ratchet straps. I have had faulty equipment trip the breakers on my generator. Go figure!
9/25/2011 10:08:00 PM
Originally Posted By dab2:
I have a Honda 5000 generator at work I keep in the bed of my truck. It is not bolted down, just secured with ratchet straps. I have had faulty equipment trip the breakers on my generator. Go figure!
I have a Honda 5000 generator at work I keep in the bed of my truck. It is not bolted down, just secured with ratchet straps. I have had faulty equipment trip the breakers on my generator. Go figure!
There is a difference between an over current trip and a ground fault trip. Circuit breakers have ratings for both.
9/25/2011 10:43:12 PM
Originally Posted By danc46:
And if the appliance short circuits, how will it cause the breaker on the generator to trip for a ground fault?
Originally Posted By Rockyriver:
3. Don't worry about grounding the generator, it is already grounded to the appliance it is running when you plug the cord in the generator.
3. Don't worry about grounding the generator, it is already grounded to the appliance it is running when you plug the cord in the generator.
And if the appliance short circuits, how will it cause the breaker on the generator to trip for a ground fault?
It will if he is using a transfer switch with an equipment ground to earth like mine. If he is just plugging an appliance into the generator with an extension cord, then when the case gets hot and he touches the case with bare feet on concrete or dirt, especially wet concrete or dirt, then the breaker will trip right after his heart stops.
9/25/2011 10:58:03 PM
Originally Posted By Mach:
It will if he is using a transfer switch with an equipment ground to earth like mine. If he is just plugging an appliance into the generator with an extension cord, then when the case gets hot and he touches the case with bare feet on concrete or dirt, especially wet concrete or dirt, then the breaker will trip right after his heart stops.
Originally Posted By danc46:
And if the appliance short circuits, how will it cause the breaker on the generator to trip for a ground fault?
Originally Posted By Rockyriver:
3. Don't worry about grounding the generator, it is already grounded to the appliance it is running when you plug the cord in the generator.
3. Don't worry about grounding the generator, it is already grounded to the appliance it is running when you plug the cord in the generator.
And if the appliance short circuits, how will it cause the breaker on the generator to trip for a ground fault?
It will if he is using a transfer switch with an equipment ground to earth like mine. If he is just plugging an appliance into the generator with an extension cord, then when the case gets hot and he touches the case with bare feet on concrete or dirt, especially wet concrete or dirt, then the breaker will trip right after his heart stops.
Okay, so installing a ground rod in the soil and attaching wire to the frame of the generator will make it safe?
9/25/2011 11:30:03 PM
Originally Posted By dab2:
Okay, so installing a ground rod in the soil and attaching wire to the frame of the generator will make it safe?
Originally Posted By Mach:
It will if he is using a transfer switch with an equipment ground to earth like mine. If he is just plugging an appliance into the generator with an extension cord, then when the case gets hot and he touches the case with bare feet on concrete or dirt, especially wet concrete or dirt, then the breaker will trip right after his heart stops.
Originally Posted By danc46:
And if the appliance short circuits, how will it cause the breaker on the generator to trip for a ground fault?
Originally Posted By Rockyriver:
3. Don't worry about grounding the generator, it is already grounded to the appliance it is running when you plug the cord in the generator.
3. Don't worry about grounding the generator, it is already grounded to the appliance it is running when you plug the cord in the generator.
And if the appliance short circuits, how will it cause the breaker on the generator to trip for a ground fault?
It will if he is using a transfer switch with an equipment ground to earth like mine. If he is just plugging an appliance into the generator with an extension cord, then when the case gets hot and he touches the case with bare feet on concrete or dirt, especially wet concrete or dirt, then the breaker will trip right after his heart stops.
Okay, so installing a ground rod in the soil and attaching wire to the frame of the generator will make it safe?
Sort of.
All of the metal parts of the portable gen set should be bonded to the generator case and the generator casing should be bonded to the neutral wire of the outlets mounted on the gen set. That is how they are made.
The problem develops if any of these metal conducting parts are not bonded ( the connections break ) and somehow those parts become hot. Also by grounding the case to earth you ensure there is no static build up on the metal parts.
I don't think any contractors ever earth ground their generators on site.
The safety factor is that the neutral wire is connected to the equipment ground on the gen set. That will trip the breaker if the casing of anything you are using, including the gen set, touches the hot wire.
There may be some older portable generators that are not set up this way and maybe some large non-portable whole house gen sets not set up that way, I don't know.
At least that is how I understand it. If all the connections are connected like they are supposed to be it should be good to go.
ETA: if the connections are not like they are supposed to be due to age, corrosion or vibration, then having the casing of the Generator equipment ground tied to an earth ground adds safety.
9/26/2011 1:50:19 PM
So what do I need to do to ground the generator?
What sort of wire do I need to use and how long does the metal stake need to be?
What sort of wire do I need to use and how long does the metal stake need to be?
9/26/2011 2:25:44 PM
Originally Posted By johnpfw:
So what do I need to do to ground the generator?
What sort of wire do I need to use and how long does the metal stake need to be?
So what do I need to do to ground the generator?
What sort of wire do I need to use and how long does the metal stake need to be?
For my 8000KWH generator, I used a 4', 1/2" copper rod and pounded it 3' into the ground. Then used a copper clamp and clamp a #8awg wire to ground stake whenever I use the generator. You should be able to get away with a smaller 3/8" rod and #12 awg cable.
9/28/2011 9:37:38 PM
I never ground mine. If your hot goes to the frame it will trip the breaker. I'm not telling you to do this, have a qualified person strip a extension cord and touch the hot to the frame of the generator and the breaker will trip. Older houses don't have grounded receptacles.
9/28/2011 10:34:09 PM
Originally Posted By johnpfw:
Yamaha EF2000iS
1600 / 2000 Watts
13.3 / 16.7 Amps
1) Will a 12 gauge 15 amp extension cord (12/3) be OK ?
12 gauge is pretty heavy duty for 15A. Unless it is a very long cord it should be fine.
2) Manual is confusing (for me) as to what oil to use. Am not expecting to use in very cold temperatures. Will I be OK with 10W-40 fully synthetic?
Outside of my area of expertise so I will pass on it.
3) Manual talks about grounding the generator if using with a grounded appliance. Huh?
No idea what that refers to. Virtually every portable generator has a bond (electrical connection) between the frame and neutral. The frame is connected to the ground pin in the outlet on the generator. That is all that is needed for safety.
Yamaha EF2000iS
1600 / 2000 Watts
13.3 / 16.7 Amps
1) Will a 12 gauge 15 amp extension cord (12/3) be OK ?
12 gauge is pretty heavy duty for 15A. Unless it is a very long cord it should be fine.
2) Manual is confusing (for me) as to what oil to use. Am not expecting to use in very cold temperatures. Will I be OK with 10W-40 fully synthetic?
Outside of my area of expertise so I will pass on it.
3) Manual talks about grounding the generator if using with a grounded appliance. Huh?
No idea what that refers to. Virtually every portable generator has a bond (electrical connection) between the frame and neutral. The frame is connected to the ground pin in the outlet on the generator. That is all that is needed for safety.
No doubt you will get all kinds of dubious advice about ground rods and how necessary they are to make your generator safe. That is just plain nonsense. A ground rod does virtually nothing for this kind of installation. You can't get enough current through the earth if you get a fault to earth no matter what, so the idea that you will reduce risk of electrocution via a ground rod is just so far from reality to be laughable, if it was not such a pervasive belief.
Originally Posted By danc46:
And if the appliance short circuits, how will it cause the breaker on the generator to trip for a ground fault?
And if the appliance short circuits, how will it cause the breaker on the generator to trip for a ground fault?
A fault to a metal part such as on your refrigerator will trip the CB on the generator as you will end up with a dead short between L and ground. This is exactly the same way the CB in your house protects you from a similar fault. The fault current path is from L to either N or the green wire that trips the CB. It is not the current through earth and the ground rod. There is just not enough current that could be there to trip the CB. It will take about 75A or more to trip a 15A CB on the magnetic side. No way your earth path is low enough resistance to do that. Ohm's law says it cannot happen. Often the earth resistance is well into double digits, even higher. To get a magnetic trip on energizing earth it would need to be less then 2 Ohms. An earth resistance that low is very, very rare.
9/29/2011 10:49:03 AM
Originally Posted By ilbob:
No doubt you will get all kinds of dubious advice about ground rods and how necessary they are to make your generator safe. That is just plain nonsense. A ground rod does virtually nothing for this kind of installation. You can't get enough current through the earth if you get a fault to earth no matter what, so the idea that you will reduce risk of electrocution via a ground rod is just so far from reality to be laughable, if it was not such a pervasive belief.
A fault to a metal part such as on your refrigerator will trip the CB on the generator as you will end up with a dead short between L and ground. This is exactly the same way the CB in your house protects you from a similar fault. The fault current path is from L to either N or the green wire that trips the CB. It is not the current through earth and the ground rod. There is just not enough current that could be there to trip the CB. It will take about 75A or more to trip a 15A CB on the magnetic side. No way your earth path is low enough resistance to do that. Ohm's law says it cannot happen. Often the earth resistance is well into double digits, even higher. To get a magnetic trip on energizing earth it would need to be less then 2 Ohms. An earth resistance that low is very, very rare.
Originally Posted By johnpfw:
Yamaha EF2000iS
1600 / 2000 Watts
13.3 / 16.7 Amps
1) Will a 12 gauge 15 amp extension cord (12/3) be OK ?
12 gauge is pretty heavy duty for 15A. Unless it is a very long cord it should be fine.
2) Manual is confusing (for me) as to what oil to use. Am not expecting to use in very cold temperatures. Will I be OK with 10W-40 fully synthetic?
Outside of my area of expertise so I will pass on it.
3) Manual talks about grounding the generator if using with a grounded appliance. Huh?
No idea what that refers to. Virtually every portable generator has a bond (electrical connection) between the frame and neutral. The frame is connected to the ground pin in the outlet on the generator. That is all that is needed for safety.
Yamaha EF2000iS
1600 / 2000 Watts
13.3 / 16.7 Amps
1) Will a 12 gauge 15 amp extension cord (12/3) be OK ?
12 gauge is pretty heavy duty for 15A. Unless it is a very long cord it should be fine.
2) Manual is confusing (for me) as to what oil to use. Am not expecting to use in very cold temperatures. Will I be OK with 10W-40 fully synthetic?
Outside of my area of expertise so I will pass on it.
3) Manual talks about grounding the generator if using with a grounded appliance. Huh?
No idea what that refers to. Virtually every portable generator has a bond (electrical connection) between the frame and neutral. The frame is connected to the ground pin in the outlet on the generator. That is all that is needed for safety.
No doubt you will get all kinds of dubious advice about ground rods and how necessary they are to make your generator safe. That is just plain nonsense. A ground rod does virtually nothing for this kind of installation. You can't get enough current through the earth if you get a fault to earth no matter what, so the idea that you will reduce risk of electrocution via a ground rod is just so far from reality to be laughable, if it was not such a pervasive belief.
Originally Posted By danc46:
And if the appliance short circuits, how will it cause the breaker on the generator to trip for a ground fault?
And if the appliance short circuits, how will it cause the breaker on the generator to trip for a ground fault?
A fault to a metal part such as on your refrigerator will trip the CB on the generator as you will end up with a dead short between L and ground. This is exactly the same way the CB in your house protects you from a similar fault. The fault current path is from L to either N or the green wire that trips the CB. It is not the current through earth and the ground rod. There is just not enough current that could be there to trip the CB. It will take about 75A or more to trip a 15A CB on the magnetic side. No way your earth path is low enough resistance to do that. Ohm's law says it cannot happen. Often the earth resistance is well into double digits, even higher. To get a magnetic trip on energizing earth it would need to be less then 2 Ohms. An earth resistance that low is very, very rare.
A ground fault is different than an overcurrent fault.
9/29/2011 6:31:32 PM
Originally Posted By danc46:
A ground fault is different than an overcurrent fault.
A ground fault is different than an overcurrent fault.
perhaps you would be willing to lend us the benefit of your expertise in this matter and explain to us the difference.
9/29/2011 7:10:02 PM
Originally Posted By ilbob:
perhaps you would be willing to lend us the benefit of your expertise in this matter and explain to us the difference.
Originally Posted By danc46:
A ground fault is different than an overcurrent fault.
A ground fault is different than an overcurrent fault.
perhaps you would be willing to lend us the benefit of your expertise in this matter and explain to us the difference.
I copied this from http://www.howstuffworks.com/question117.htm. It is for a GFCI but it is the same principal.
That outlet is called a ground-fault circuit interrupter (GFCI). It's there to protect people from electrical shock, so it is completely different from a fuse.
The question on appliance plugs talks about fuses. The idea behind a fuse is to protect a house from an electrical fire. If the hot wire were to accidentally touch the neutral wire for some reason (say, because a mouse chews through the insulation, or someone drives a nail through the wire while hanging a picture, or the vacuum cleaner sucks up an outlet cord and cuts it), an incredible amount of current will flow through the circuit and start heating it up like one of the coils in a toaster. The fuse heats up faster than the wire and burns out before the wire can start a fire.
A GFCI is much more subtle. When you look at a normal 120-volt outlet in the United States, there are two vertical slots and then a round hole centered below them. The left slot is slightly larger than the right. The left slot is called "neutral," the right slot is called "hot" and the hole below them is called "ground." If an appliance is working properly, all electricity that the appliance uses will flow from hot to neutral. A GFCI monitors the amount of current flowing from hot to neutral. If there is any imbalance, it trips the circuit. It is able to sense a mismatch as small as 4 or 5 milliamps, and it can react as quickly as one-thirtieth of a second.
So let's say you are outside with your power drill and it is raining. You are standing on the ground, and since the drill is wet there is a path from the hot wire inside the drill through you to ground (see How Power Distribution Grids Work for details on grounding). If electricity flows from hot to ground through you, it could be fatal. The GFCI can sense the current flowing through you because not all of the current is flowing from hot to neutral as it expects –– some of it is flowing through you to ground. As soon as the GFCI senses that, it trips the circuit and cuts off the electricity.
9/29/2011 7:10:52 PM
Originally Posted By Mach:
The safety factor is that the neutral wire is connected to the equipment ground on the gen set. That will trip the breaker if the casing of anything you are using, including the gen set, touches the hot wire.
The safety factor is that the neutral wire is connected to the equipment ground on the gen set. That will trip the breaker if the casing of anything you are using, including the gen set, touches the hot wire.
this is not the case on Honda inverter generators specifically, and is not guaranteed generally.
for example, the popular Honda EU2000i does *not* bond the neutral to the ground.
see pages 17 (wording) and 55 (diagram) of the EU2000i user manual (pdf).
GROUND SYSTEM
Connections for standby power to a building electrical system must be
made by a qualified electrician. The connection must isolate the
generator power from utility power, and must comply with all
applicable laws and electrical codes.
Honda portable generators have a system ground that connects
generator frame components to the ground terminals in the AC output
receptacles. The system ground is not connected to the AC neutral
wire. If the generator is tested by a receptacle tester, it will not show
the same ground circuit condition as for a home receptacle.
ar-jedi
9/29/2011 7:28:09 PM
Let's put it simply for you guys. There are two "grounds" in a system. The GROUNDED WIRE/SYSTEM NEUTRAL carries current all the time. It is the white or gray wire.
The green or bare wire is the safety ground, the GROUNDING CONDUCTOR that never carries current except in a ground fault/short circuit.
The only place they are tied together is at the voltage source/service panel/generator/etc. and that is tied to a grounding rod/bar/system.
The grounding conductor will trip a breaker faster in a ground fault/short circuit than waiting for it to trip on an over current fault.
If you tie your standby generator in with a transfer switch, the generator ground should be grounded to the same grounding system that is in your electrical distribution system.
In some instances now, the grounded conductor as well as the line wires are switched.
Read the labels on your gensets. Many of them will say "Safety Ground not Bonded to System Ground", etc. meaning you have a floating neutral. That is NOT a good thing.
This can get into a nightmare trying to explain these things.
Even licensed electricians/contractors and professional engineers get this shit crossed up.
The green or bare wire is the safety ground, the GROUNDING CONDUCTOR that never carries current except in a ground fault/short circuit.
The only place they are tied together is at the voltage source/service panel/generator/etc. and that is tied to a grounding rod/bar/system.
The grounding conductor will trip a breaker faster in a ground fault/short circuit than waiting for it to trip on an over current fault.
If you tie your standby generator in with a transfer switch, the generator ground should be grounded to the same grounding system that is in your electrical distribution system.
In some instances now, the grounded conductor as well as the line wires are switched.
Read the labels on your gensets. Many of them will say "Safety Ground not Bonded to System Ground", etc. meaning you have a floating neutral. That is NOT a good thing.
This can get into a nightmare trying to explain these things.
Even licensed electricians/contractors and professional engineers get this shit crossed up.
9/29/2011 7:44:54 PM
If you have a floating neutral you wouldn't read 120v from the outlet. The neutral is bonded to the frame as is the ground just not at the same place. If you are feeding your panel (with your main turned off I hope) you would be using your house neutral that is grounded.
9/29/2011 8:55:02 PM
250.34 Portable and Vehicle-Mounted Generators.
(A) Portable Generators. The frame of a portable generator shall not be required to be connected to a grounding electrode as defined in 250.52 for a system supplied by the generator under the following conditions:
(1) The generator supplies only equipment mounted on the generator, cord-and-plug-connected equipment through receptacles mounted on the generator, or both, and
(2) The non–current-carrying metal parts of equipment and the equipment grounding conductor terminals of the receptacles are bonded to the generator frame.
(B) Vehicle-Mounted Generators. The frame of a vehicle shall not be required to be connected to a grounding electrode as defined in 250.52 for a system supplied by a generator located on this vehicle under the following conditions:
(1) The frame of the generator is bonded to the vehicle frame, and
(2) The generator supplies only equipment located on the vehicle or cord-and-plug-connected equipment through receptacles mounted on the vehicle, or both equipment located on the vehicle and cord-and-plug-connected equipment through receptacles mounted on the vehicle or on the generator, and
(3) The non–current-carrying metal parts of equipment and the equipment grounding conductor terminals of the receptacles are bonded to the generator frame.
(A) Portable Generators. The frame of a portable generator shall not be required to be connected to a grounding electrode as defined in 250.52 for a system supplied by the generator under the following conditions:
(1) The generator supplies only equipment mounted on the generator, cord-and-plug-connected equipment through receptacles mounted on the generator, or both, and
(2) The non–current-carrying metal parts of equipment and the equipment grounding conductor terminals of the receptacles are bonded to the generator frame.
(B) Vehicle-Mounted Generators. The frame of a vehicle shall not be required to be connected to a grounding electrode as defined in 250.52 for a system supplied by a generator located on this vehicle under the following conditions:
(1) The frame of the generator is bonded to the vehicle frame, and
(2) The generator supplies only equipment located on the vehicle or cord-and-plug-connected equipment through receptacles mounted on the vehicle, or both equipment located on the vehicle and cord-and-plug-connected equipment through receptacles mounted on the vehicle or on the generator, and
(3) The non–current-carrying metal parts of equipment and the equipment grounding conductor terminals of the receptacles are bonded to the generator frame.
9/29/2011 9:50:54 PM
Originally Posted By chadweasel:
If you have a floating neutral you wouldn't read 120v from the outlet. The neutral is bonded to the frame as is the ground just not at the same place. If you are feeding your panel (with your main turned off I hope) you would be using your house neutral that is grounded.
If you have a floating neutral you wouldn't read 120v from the outlet. The neutral is bonded to the frame as is the ground just not at the same place. If you are feeding your panel (with your main turned off I hope) you would be using your house neutral that is grounded.
Floating neutral occurs when there is no bonding to a grounding rod, etc.
Where is the grounding rod on a generator unless you tie it into one?
You have a floating neutral on a generator that is not grounded but it doesn't matter if it just services devices through cords.
You will read 110v between one line and the neutral on a generator that is not bonded to ground.
Tieing a standby generator into a service panel through an autotransfer switch, the neutral/system ground may or may not be switched too. But the standby generator grounded and grounding conductor (neutral and safety ground) should be tied into the service panel and BONDED there. But the safety ground from the generator should definitely tie into the service panel grounding bus.
9/29/2011 10:13:46 PM
Originally Posted By chadweasel:
I copied this from http://www.howstuffworks.com/question117.htm. It is for a GFCI but it is the same principal.
That outlet is called a ground-fault circuit interrupter (GFCI). It's there to protect people from electrical shock, so it is completely different from a fuse.
The question on appliance plugs talks about fuses. The idea behind a fuse is to protect a house from an electrical fire. If the hot wire were to accidentally touch the neutral wire for some reason (say, because a mouse chews through the insulation, or someone drives a nail through the wire while hanging a picture, or the vacuum cleaner sucks up an outlet cord and cuts it), an incredible amount of current will flow through the circuit and start heating it up like one of the coils in a toaster. The fuse heats up faster than the wire and burns out before the wire can start a fire.
A GFCI is much more subtle. When you look at a normal 120-volt outlet in the United States, there are two vertical slots and then a round hole centered below them. The left slot is slightly larger than the right. The left slot is called "neutral," the right slot is called "hot" and the hole below them is called "ground." If an appliance is working properly, all electricity that the appliance uses will flow from hot to neutral. A GFCI monitors the amount of current flowing from hot to neutral. If there is any imbalance, it trips the circuit. It is able to sense a mismatch as small as 4 or 5 milliamps, and it can react as quickly as one-thirtieth of a second.
So let's say you are outside with your power drill and it is raining. You are standing on the ground, and since the drill is wet there is a path from the hot wire inside the drill through you to ground (see How Power Distribution Grids Work for details on grounding). If electricity flows from hot to ground through you, it could be fatal. The GFCI can sense the current flowing through you because not all of the current is flowing from hot to neutral as it expects –– some of it is flowing through you to ground. As soon as the GFCI senses that, it trips the circuit and cuts off the electricity.
Originally Posted By ilbob:
perhaps you would be willing to lend us the benefit of your expertise in this matter and explain to us the difference.
Originally Posted By danc46:
A ground fault is different than an overcurrent fault.
A ground fault is different than an overcurrent fault.
perhaps you would be willing to lend us the benefit of your expertise in this matter and explain to us the difference.
I copied this from http://www.howstuffworks.com/question117.htm. It is for a GFCI but it is the same principal.
That outlet is called a ground-fault circuit interrupter (GFCI). It's there to protect people from electrical shock, so it is completely different from a fuse.
The question on appliance plugs talks about fuses. The idea behind a fuse is to protect a house from an electrical fire. If the hot wire were to accidentally touch the neutral wire for some reason (say, because a mouse chews through the insulation, or someone drives a nail through the wire while hanging a picture, or the vacuum cleaner sucks up an outlet cord and cuts it), an incredible amount of current will flow through the circuit and start heating it up like one of the coils in a toaster. The fuse heats up faster than the wire and burns out before the wire can start a fire.
A GFCI is much more subtle. When you look at a normal 120-volt outlet in the United States, there are two vertical slots and then a round hole centered below them. The left slot is slightly larger than the right. The left slot is called "neutral," the right slot is called "hot" and the hole below them is called "ground." If an appliance is working properly, all electricity that the appliance uses will flow from hot to neutral. A GFCI monitors the amount of current flowing from hot to neutral. If there is any imbalance, it trips the circuit. It is able to sense a mismatch as small as 4 or 5 milliamps, and it can react as quickly as one-thirtieth of a second.
So let's say you are outside with your power drill and it is raining. You are standing on the ground, and since the drill is wet there is a path from the hot wire inside the drill through you to ground (see How Power Distribution Grids Work for details on grounding). If electricity flows from hot to ground through you, it could be fatal. The GFCI can sense the current flowing through you because not all of the current is flowing from hot to neutral as it expects –– some of it is flowing through you to ground. As soon as the GFCI senses that, it trips the circuit and cuts off the electricity.
A GFCI senses the difference in current between the two conductors and will trip if there is 5 milliamps difference.
That can be bleed off by induction to earth if the cord is laying on the ground.
That has nothing to do with an actual short circuit/ground fault.
Over current is a finite amount of current larger than the overcurrent device will tolerate.
A ground fault/short circuit is instantanedous, infinite amperage that will hold as long as the conductor will hold it.
Breakers and fuses will trip quicker on a ground fault than on a over current fault if the current is led to build up ASAP.
A grounding conductor will let the amperage flow minimizing trip time on the over current device (fuse, circuit breaker) where on an over current fault, the heat from the overcurrent will be slow and the trip time longer.
9/30/2011 3:34:56 PM
Just got off the phone with an English speaking American, working in America, Honda technician. I told him I have a Honda EU3000iS generator. I told him I use it as emergency power for my fridge, freezer, etc. and use high grade 12 gauge extension cords while running said appliances. I asked him if there was any reason I needed to use an actual ground rod and connect it to the frame to keep from being shocked/electrocuted if the case went hot. He said there is NO reason to use a grounding system on my generator because they are internally protected. The way I am using it is how it was designed to be used. The ONLY exception would be for some off the wall building code that would require a different grounding system to run a furnace/air conditioner....So the short and correct answer is that you do NOT need a separate ground to the generator to be safe(r).
10/1/2011 8:53:09 AM
I highly recommend every one that has a code book to read and fully understand 90.1(C), especially the last clause. It explains a lot, even though in most cases, nothing in the pre 100 chapters is enforceable.
Floating neutral is also not a NEC defined term. The NEC requires a bond between the EGC (equipment grounding conductor) and the N. It has little to do with the grounding electrode, other than the grounding electrode has to be tied to that point as well. In most homes, the N-G bond is actually a screw that goes through the N bus into the skin of the panel board and thus ties into the ground bus. The GEC (grounding electrode conductor) is brought into the N bus from the GES (grounding electrode system). It can be done in other ways, but this is probably the most common way.
ETA: Most common in houses anyway. Not so in apartment buildings and condos, but many if not most of them are not 120/240 systems anyway.
Grounding electrode being a ground rod or other GE as defined in 250.52.
Has nothing to do with any N-G bond.
Being as there is no GFCI involved in this discussion, it seems pointless to bring up googled information on it.
I would be really surprised to find that a portable generator did not have a N-G bond in it being as if the frame were to become energized the CB would not trip (unless it was also a GFCI). There would be no reason to even have the green wire. I don't know what the Honda manual means by talking about system grounds and such. That is not a NEC defined term.
Originally Posted By danc46:
Floating neutral occurs when there is no bonding to a grounding rod, etc. Where is the grounding rod on a generator unless you tie it into one?
You have a floating neutral on a generator that is not grounded but it doesn't matter if it just services devices through cords.
You will read 110v between one line and the neutral on a generator that is not bonded to ground.
Tieing a standby generator into a service panel through an autotransfer switch, the neutral/system ground may or may not be switched too. But the standby generator grounded and grounding conductor (neutral and safety ground) should be tied into the service panel and BONDED there. But the safety ground from the generator should definitely tie into the service panel grounding bus.
Originally Posted By chadweasel:
If you have a floating neutral you wouldn't read 120v from the outlet. The neutral is bonded to the frame as is the ground just not at the same place. If you are feeding your panel (with your main turned off I hope) you would be using your house neutral that is grounded.
If you have a floating neutral you wouldn't read 120v from the outlet. The neutral is bonded to the frame as is the ground just not at the same place. If you are feeding your panel (with your main turned off I hope) you would be using your house neutral that is grounded.
Floating neutral occurs when there is no bonding to a grounding rod, etc. Where is the grounding rod on a generator unless you tie it into one?
You have a floating neutral on a generator that is not grounded but it doesn't matter if it just services devices through cords.
You will read 110v between one line and the neutral on a generator that is not bonded to ground.
Tieing a standby generator into a service panel through an autotransfer switch, the neutral/system ground may or may not be switched too. But the standby generator grounded and grounding conductor (neutral and safety ground) should be tied into the service panel and BONDED there. But the safety ground from the generator should definitely tie into the service panel grounding bus.
Floating neutral is also not a NEC defined term. The NEC requires a bond between the EGC (equipment grounding conductor) and the N. It has little to do with the grounding electrode, other than the grounding electrode has to be tied to that point as well. In most homes, the N-G bond is actually a screw that goes through the N bus into the skin of the panel board and thus ties into the ground bus. The GEC (grounding electrode conductor) is brought into the N bus from the GES (grounding electrode system). It can be done in other ways, but this is probably the most common way.
ETA: Most common in houses anyway. Not so in apartment buildings and condos, but many if not most of them are not 120/240 systems anyway.
Originally Posted By chadweasel:
250.34 Portable and Vehicle-Mounted Generators.
(A) Portable Generators. The frame of a portable generator shall not be required to be connected to a grounding electrode as defined in 250.52 for a system supplied by the generator under the following conditions:
(
250.34 Portable and Vehicle-Mounted Generators.
(A) Portable Generators. The frame of a portable generator shall not be required to be connected to a grounding electrode as defined in 250.52 for a system supplied by the generator under the following conditions:
(
Grounding electrode being a ground rod or other GE as defined in 250.52.
Has nothing to do with any N-G bond.
Being as there is no GFCI involved in this discussion, it seems pointless to bring up googled information on it.
I would be really surprised to find that a portable generator did not have a N-G bond in it being as if the frame were to become energized the CB would not trip (unless it was also a GFCI). There would be no reason to even have the green wire. I don't know what the Honda manual means by talking about system grounds and such. That is not a NEC defined term.
10/1/2011 10:05:35 AM
Originally Posted By ilbob:
I highly recommend every one that has a code book to read and fully understand 90.1(C), especially the last clause. It explains a lot, even though in most cases, nothing in the pre 100 chapters is enforceable.
Floating neutral is also not a NEC defined term. The NEC requires a bond between the EGC (equipment grounding conductor) and the N. It has little to do with the grounding electrode, other than the grounding electrode has to be tied to that point as well. In most homes, the N-G bond is actually a screw that goes through the N bus into the skin of the panel board and thus ties into the ground bus. The GEC (grounding electrode conductor) is brought into the N bus from the GES (grounding electrode system). It can be done in other ways, but this is probably the most common way.
Grounding electrode being a ground rod or other GE as defined in 250.52.
Has nothing to do with any N-G bond.
Being as there is no GFCI involved in this discussion, it seems pointless to bring up googled information on it.
I would be really surprised to find that a portable generator did not have a N-G bond in it being as if the frame were to become energized the CB would not trip (unless it was also a GFCI). There would be no reason to even have the green wire. I don't know what the Honda manual means by talking about system grounds and such. That is not a NEC defined term.
I highly recommend every one that has a code book to read and fully understand 90.1(C), especially the last clause. It explains a lot, even though in most cases, nothing in the pre 100 chapters is enforceable.
Originally Posted By danc46:
Floating neutral occurs when there is no bonding to a grounding rod, etc. Where is the grounding rod on a generator unless you tie it into one?
You have a floating neutral on a generator that is not grounded but it doesn't matter if it just services devices through cords.
You will read 110v between one line and the neutral on a generator that is not bonded to ground.
Tieing a standby generator into a service panel through an autotransfer switch, the neutral/system ground may or may not be switched too. But the standby generator grounded and grounding conductor (neutral and safety ground) should be tied into the service panel and BONDED there. But the safety ground from the generator should definitely tie into the service panel grounding bus.
Originally Posted By chadweasel:
If you have a floating neutral you wouldn't read 120v from the outlet. The neutral is bonded to the frame as is the ground just not at the same place. If you are feeding your panel (with your main turned off I hope) you would be using your house neutral that is grounded.
If you have a floating neutral you wouldn't read 120v from the outlet. The neutral is bonded to the frame as is the ground just not at the same place. If you are feeding your panel (with your main turned off I hope) you would be using your house neutral that is grounded.
Floating neutral occurs when there is no bonding to a grounding rod, etc. Where is the grounding rod on a generator unless you tie it into one?
You have a floating neutral on a generator that is not grounded but it doesn't matter if it just services devices through cords.
You will read 110v between one line and the neutral on a generator that is not bonded to ground.
Tieing a standby generator into a service panel through an autotransfer switch, the neutral/system ground may or may not be switched too. But the standby generator grounded and grounding conductor (neutral and safety ground) should be tied into the service panel and BONDED there. But the safety ground from the generator should definitely tie into the service panel grounding bus.
Floating neutral is also not a NEC defined term. The NEC requires a bond between the EGC (equipment grounding conductor) and the N. It has little to do with the grounding electrode, other than the grounding electrode has to be tied to that point as well. In most homes, the N-G bond is actually a screw that goes through the N bus into the skin of the panel board and thus ties into the ground bus. The GEC (grounding electrode conductor) is brought into the N bus from the GES (grounding electrode system). It can be done in other ways, but this is probably the most common way.
Originally Posted By chadweasel:
250.34 Portable and Vehicle-Mounted Generators.
(A) Portable Generators. The frame of a portable generator shall not be required to be connected to a grounding electrode as defined in 250.52 for a system supplied by the generator under the following conditions:
(
250.34 Portable and Vehicle-Mounted Generators.
(A) Portable Generators. The frame of a portable generator shall not be required to be connected to a grounding electrode as defined in 250.52 for a system supplied by the generator under the following conditions:
(
Grounding electrode being a ground rod or other GE as defined in 250.52.
Has nothing to do with any N-G bond.
Being as there is no GFCI involved in this discussion, it seems pointless to bring up googled information on it.
I would be really surprised to find that a portable generator did not have a N-G bond in it being as if the frame were to become energized the CB would not trip (unless it was also a GFCI). There would be no reason to even have the green wire. I don't know what the Honda manual means by talking about system grounds and such. That is not a NEC defined term.
I just used the GFCI as an example to explain a ground fault vs over current. Maybe it was a bad example.
10/1/2011 10:26:37 AM
Originally Posted By chadweasel:
I just used the GFCI as an example to explain a ground fault vs over current. Maybe it was a bad example.
I just used the GFCI as an example to explain a ground fault vs over current. Maybe it was a bad example.
A ground fault means only that a hot wire has inadvertently become connected to the equipment grounding conductor or other conductive part. In a 240/120 system that most residences have, that will immediately trip a breaker somewhere preventing an electrical shock if someone where to touch an exposed conductive part that had become inadvertently energized.
GFCIs are about dealing with low level current leakages (> 5 mA IIRC) that while they may be potentially lethal, there is not enough current to trip a breaker. It is possible to have a ground fault of this type, such as the classic of dropping a hair dryer into a bathtub, that just plain does not generate enough fault current to trip a CB.
10/1/2011 10:53:54 AM
Originally Posted By ilbob:
A ground fault means only that a hot wire has inadvertently become connected to the equipment grounding conductor or other conductive part. In a 240/120 system that most residences have, that will immediately trip a breaker somewhere preventing an electrical shock if someone where to touch an exposed conductive part that had become inadvertently energized.
GFCIs are about dealing with low level current leakages (> 5 mA IIRC) that while they may be potentially lethal, there is not enough current to trip a breaker. It is possible to have a ground fault of this type, such as the classic of dropping a hair dryer into a bathtub, that just plain does not generate enough fault current to trip a CB.
Originally Posted By chadweasel:
I just used the GFCI as an example to explain a ground fault vs over current. Maybe it was a bad example.
I just used the GFCI as an example to explain a ground fault vs over current. Maybe it was a bad example.
A ground fault means only that a hot wire has inadvertently become connected to the equipment grounding conductor or other conductive part. In a 240/120 system that most residences have, that will immediately trip a breaker somewhere preventing an electrical shock if someone where to touch an exposed conductive part that had become inadvertently energized.
GFCIs are about dealing with low level current leakages (> 5 mA IIRC) that while they may be potentially lethal, there is not enough current to trip a breaker. It is possible to have a ground fault of this type, such as the classic of dropping a hair dryer into a bathtub, that just plain does not generate enough fault current to trip a CB.
Like I said, maybe it was a bad example. I understand what a GFCI is and what it does. You are doing a good job at explaining the answer to a problem that has already been solved. (look above your first post)
10/1/2011 10:55:30 AM
Ever play Guitar on a concrete floor then touch your lips to the microphone to have your hair stand on end?
That's the other ground they're talking about.
Tj
That's the other ground they're talking about.
Tj
10/1/2011 11:00:34 AM
Originally Posted By TomJefferson:
Ever play Guitar on a concrete floor then touch your lips to the microphone to have your hair stand on end?
That's the other ground they're talking about.
Tj
Ever play Guitar on a concrete floor then touch your lips to the microphone to have your hair stand on end?
That's the other ground they're talking about.
Tj
That is not another ground so much as it is a piece of equipment that is likely wired or modified incorrectly. It is not unusual for PA systems to be hacked by well meaning but clueless people.
Every few years there is another story out there about someone getting electrocuted in a baptismal while using a microphone. It is almost always traced to something that has been wired, repaired or modified improperly, although it could also be a failure.
10/1/2011 11:36:47 AM
Originally Posted By ilbob:
That is not another ground so much as it is a piece of equipment that is likely wired or modified incorrectly. It is not unusual for PA systems to be hacked by well meaning but clueless people.
Every few years there is another story out there about someone getting electrocuted in a baptismal while using a microphone. It is almost always traced to something that has been wired, repaired or modified improperly, although it could also be a failure.
Originally Posted By TomJefferson:
Ever play Guitar on a concrete floor then touch your lips to the microphone to have your hair stand on end?
That's the other ground they're talking about.
Tj
Ever play Guitar on a concrete floor then touch your lips to the microphone to have your hair stand on end?
That's the other ground they're talking about.
Tj
That is not another ground so much as it is a piece of equipment that is likely wired or modified incorrectly. It is not unusual for PA systems to be hacked by well meaning but clueless people.
Every few years there is another story out there about someone getting electrocuted in a baptismal while using a microphone. It is almost always traced to something that has been wired, repaired or modified improperly, although it could also be a failure.
Never seen a preacher play an elecytric guitar while holding a microphone in a Baptismal.
10/6/2011 10:29:38 AM
Originally Posted By ilbob:
Grounding electrode being a ground rod or other GE as defined in 250.52.
Has nothing to do with any N-G bond.
Being as there is no GFCI involved in this discussion, it seems pointless to bring up googled information on it.
I would be really surprised to find that a portable generator did not have a N-G bond in it being as if the frame were to become energized the CB would not trip (unless it was also a GFCI). There would be no reason to even have the green wire. I don't know what the Honda manual means by talking about system grounds and such. That is not a NEC defined term.
Grounding electrode being a ground rod or other GE as defined in 250.52.
Has nothing to do with any N-G bond.
Being as there is no GFCI involved in this discussion, it seems pointless to bring up googled information on it.
I would be really surprised to find that a portable generator did not have a N-G bond in it being as if the frame were to become energized the CB would not trip (unless it was also a GFCI). There would be no reason to even have the green wire. I don't know what the Honda manual means by talking about system grounds and such. That is not a NEC defined term.
A floating neutral means it is NOT tied to a ground rod. It can cause voltage fluctuations and makes the distribution system more vulnerable to inductive loading, voltage drop, etc. Small gensets like the Honda give the option of bonding the neutral and ground or not.
Bonding is basic to any AC distribution system.
If your neutral and safety ground are not bonded at the service, you are asking for all kinds of problems.
When you tie in a genset through a transfer switch in an emergency situation, all kinds of goofy things can happen. The proper way is to tie the genset neutral to the system neutral and the genset safety/frame ground to the system safety ground.
That way the bonding cannot be in question and problems are avoided.
That is why most gensets do not have the system neutral/ground tied to the frame/equipment ground on the genset.
That way the owner is given the option of one or the other.
10/16/2011 8:45:55 PM
I used the oil my generator came with at first. Then I changed it with 10w30 Royal Purple. After 3 years of that (randomly run) I changed to 10w30 AMSOIL 25k Interval oil. My 5000 Colman with the Subaru Engine purrs like a kitten after getting high on catnip. 
It's 6 years old and still looks like new. Do yourself a favor, KEEP THE ORIGINAL BOX! I kept the bottom sealed. Then flipped it over, cut off the flaps, and cut out round area for the wheels. Now I have a free generator cover to protect from dust, ect........ Thus, still looks like brand new.
It's 6 years old and still looks like new. Do yourself a favor, KEEP THE ORIGINAL BOX! I kept the bottom sealed. Then flipped it over, cut off the flaps, and cut out round area for the wheels. Now I have a free generator cover to protect from dust, ect........ Thus, still looks like brand new.