are surge protectors effective on generators?

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Ok so I noticed on my surge protector it has a red not grounded light illuminated whenever I use it on my generator. The green light is still illuminated and says protected. I checked the ground wire on my generator and it has a nice clean ground. I heard that portable generators are grounded differently then a house. Supposedly my surge protector is suppose to filter the power too. Whenever I plugged it into the wall outlet at my house the ground light was green. So what's the problem? Are surge protectors not effective on a generator or does it just not recognize the ground?
 
Your house is grounded to the Earth. Usually through the plumbing system or a grounding rod. The rod is usually found near the electric meter or the main circuit breaker panel. A generator also should be grounded to the Earth. I take a two foot copper pipe and drive it into the ground, about a 18 inches, next to my generator. I then connect a wire from the pipe to the grounding point or green wire on the generator. This should make the red light go away.
 
It's not related to the "earth" ground. It's most likely a neutral-ground bonding issue.

Your house has the neutral and grounds bonded usually at the main panel. If there is a wiring fault, the return path is through the "ground" and it will trip the breaker. The surge protector is looking for this connection.

Your generator may or may not have a neutral-ground bond. You can check for yourself. With the generator off and disconnected from all loads, measure continuity between the neutral and ground prongs on an outlet.

If you're using a transfer switch, and it does not switch the neutral, you should have a "floating-neutral" generator, the neutral-ground bond should be removed.
 
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So I guess when the ground it connected to the frame it's referred to as a floating ground? So does the surge protector just not recognize that type of ground, thus thinking it's not grounded?
 
If you have a "floating neutral" the ground is not a return path and will show "open." A generator configured this way should not be used "stand-alone."
 
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Originally Posted By: AandPDan
If you have a "floating neutral" the ground is not a return path and will show "open." A generator configured this way should not be used "stand-alone."


From what I see it has a ground wire connected from the engine to the frame and according to the manual all the outlets are supposed to be wired to that ground wire. Does that mean I still need to run a grounding rod? I use it as a portable generator.
 
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You don't need a ground rod.


Exactly. A ground rod alone is insufficient for faults.


I just looked at the schematic for my generator a 13HP/6500 Wattt 240 volt AC unit.

The alternator (60 Hz AC Generator) has the Neutral/Ground bonded to the frame, in addition to providing a Neutral/Ground for the generator outlets.

You want the 240 AC to go to the two "HOT" 240VAC wires in your distribution panel box via a transfer switch, AND you want a Neutral/ground wire going to the distribution panel box from the generator outlets Neutral/Ground.

In other words, you should have three wires from your generator's outlet going to your distribution panel box, a Neutral/Ground wire and two 240VAC wires.

You should never connect your generator to the distribution panel without a transfer switch or have some means of disconnecting the generator's power from your incoming feed or you could electrocute a lineman working on your line.
 
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ok so it says using a ground rod isn't necessary since it's an electrocution danger. I'm still not clear on why the not grounded light is illuminated on my surge protector? Does it only recognize an actual earth ground and not something on a generator that's just grounded to the frame? I bought two so I might just return them if they aren't effective in this application.
 
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Is your surge protector properly wired into your distribution box?

Is this a whole house surge protector sitting on or in your distribution panel?
 
Originally Posted By: MolaKule
Is your surge protector properly wired into your distribution box?

Is this a whole house surge protector sitting on or in your distribution panel?


Both lights are green when plugged into a wall outlet at my house. I use the generator to run tools and it's not connected to the house at all. I was just checking to make sure the protector wasn't messed up. The only time it shows the red not grounded light is when I have it plugged into my generator.
 
Small low-end generators, and even some of the better ones, have pretty noisy and horrid power quality. If you do a fourier transform of the frequencies, youll probably find a bimodal distribution. Youll also see some pretty bad voltage variations under larger step loads.

No surge suppressor is going to fix either as they cant put something into tighter phase control, nor can they carry enough capacitance to smooth transient blips on the voltage.

And it seems that the grounding approach isnt right either. Id imagine still that the circuitry would be able to protect against a large current inflow, which is really what you need. Id be looking at the specific line protection, not a lumped value with an assumption that it will bleed off to ground.
 
The ground wire is supposed to trip the breaker when something happens to the wire.

Suppose you cut the wire with your lawn mower. The blade will connect the neutral and the ground together and the breaker will trip.

You may have old extension cords or lamps that only have two wires, hot and neutral. They work ok, but if you cut the wire by accident and the blade doesn't connect the hot and neutral together it won't trip the breaker, so it will be dangerous.

If you cut the wire and it comes in contact with the earth ground, or the plumbing in your bathroom or kitchen, the breaker will trip, as long as the system is grounded. So this is another safety design.

I think the ground is not connected to the neutral in your generator. This might be by design or oversight. Who is the manufacturer? have you looked at a schematic or the web site?
 
It's an EG6500CL generator made by Honda. It's 6500 watts. It's an actual Honda generator. Yes I was using the 120v outlets. They are 20 amp gfci protected. It also has one 30amp 240v outlet and one 30 amp 120v locking outlet.
 
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If they are GFCI protected that is probably better than the surge strips you are using. = GROUND FAULT CIRCUIT INTERRUPTER

If they don't trip that is a good sign, in my opinion.

Since you aren't trying to wire this genset into your home system I don't know if I would worry about it.
 
It has DAVR which I guess it better then just a regular voltage regulator that a lot of generators have and they claim to hold the voltage within 1 percent so I wonder if I wasted my money on the surge protectors. I just run power tools so I'm not sure if you need to run a surge protector. The thing I liked though was that it filtered the power. Now how well it filters is beyond me.
 
Surge protectors are mainly to shunt high spikes from lightning strikes to ground.
 
Originally Posted By: motor_oil_madman
ok so it says using a ground rod isn't necessary since it's an electrocution danger. I'm still not clear on why the not grounded light is illuminated on my surge protector? Does it only recognize an actual earth ground and not something on a generator that's just grounded to the frame? I bought two so I might just return them if they aren't effective in this application.


I suspect it's trying to determine if neutral and ground are bonded, which I suspect they aren't. Doesn't matter if there's a ground rod going to the generator's ground or not, it has no way of determining that since it can only see whether there is a connection between neutral and ground. It's probably trying to tell you you've got a floating ground, but in your case you have a floating neutral.
 
You might be able to get a battery back up like for a computer that would act as a power conditioner.
 
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