Do I Need to Ground My Generator?

So, you’ve just purchased a generator. Or maybe you’re just now realizing something; That you may not have set up your generator quite right. The recent weather emergencies may have caused a backup power buying frenzy. As a result, you may have missed it in the chaos. But finally, the question has come up: Do I need to ground my generator?

Well, we can save you the trouble. We went through the latest national standards, codes, and guidelines. These regulations are from authorities like OSHA and the NEC. And this article is to help you figure out the answer to just that question! So here are some simple conditions that you need to fulfill to make sure that you DON’T need to ground your generator:


Conditions to Fulfill

deals with the grounding of portable and vehicle-mounted generators. Follow this link and scroll down to subsection (f), part (3). Using these guidelines will help you. After reading them, you can decide whether or not you should ground your portable or vehicle-mounted generator. But if you do not understand them, don’t worry.

The interpretation of the listed conditions are as follows:

  • Condition 1

Make sure all appliances are plugged into the generator. They should be directly supplied (including by an extension board).

People usually use generators in one of two ways. The first way is to supply their house through the main supply board. The other way is plugging in the appliance (motors, etc.) into the generator outlet (or receptacle) directly.

This condition holds for both portable and vehicle-mounted generators. OSHA guidelines mention that the generator has to supply power directly to the equipment. So it would help if you used the receptacles/ outlets on the generator for plugging in appliances. 

Similarly, in the case of vehicle-mounted generators, you should mount equipment directly on the vehicle’s outlets. In other words, generators should not supply electrical appliances through the main utility board.

  • Condition 2 

Make sure the metallic non-current-carrying parts are bonded to the frame of the generator. Moreover, in the case of a vehicle-mounted generator, the frame of the generator should further be bonded to the frame of the vehicle.

Any part of the generator (whether portable or vehicle-mounted) that can store current should have a bond with the frame. The way this works is that the frame of the generator becomes part of the grounding circuit. In the case of vehicle-mounted generators, the frame of the vehicle also becomes part of the circuit. Through this circuit, the excess current flows through them to get to the Earth. 

There should be no electrical separation between any part of the generator and its frame. That’s because if there is a separation between any of the generator’s non-current-carrying metallic parts and the generator frame, the current will not flow. This may cause overheating or create the risk of electric shocks. 

Remember that electrical separation also occurs because of high resistance or improper conducting material. It can harm you and your generator. 

According to OSHA guidelines, every non-current-carrying metallic part of the generator should be connected with the frame of the generator. The connection should be a low resistance conductor (e.g., a copper wire). 

In the case of vehicle-mounted generators, the generator isn’t on the ground itself. This is why the generator frame has a further bond with the vehicle frame.

  • Condition 3 

Make sure the neutral conductor of the generator is bonded to the frame. In other words, make sure it’s a bonded neutral generator.

This condition deals with bonded neutral generators and floating neutral generators. In a nutshell, the difference between the two is that neutral bonded generators have the neutral conductor/ wire bonded to the frame of the generator itself. Floating generators don’t. 

Again, this condition applies to both portable and vehicle-mounted generators. Also, remember; all these conditions apply in tandem. You have to make sure all the conditions are being fulfilled simultaneously. If you’re going to be supplying power to electrical appliances directly, your generator should be a ‘bonded neutral generator.’ Otherwise, you should ground your generator. 

However, you should know that if you’re using a floating neutral generator to supply your house, the grounding procedure is a bit different. There is more detail on this below.

So, we’ve discussed when you can leave off grounding your generator. Now let’s discuss when you can’t leave it off.


Situations That Require Grounding Your Generator

  • Situation 1

You’re using the generator as a backup for your home’s utility power supply. Article 250 of the National Electrical Code (NEC) covers the grounding requirements of electrical systems that involve transfer switches and generators.

When generators supply power to homes and other buildings, they should do this via a transfer switch. Now here’s the difference between the grounding of a bonded neutral generator and a floating neutral generator. Floating neutral generators are typically used for supplying backup power to residential structures. These residential structures may include homes and buildings. 

In this type of generator, the grounding is simple. Just use the transfer switch to switch the live wire only. As a result, the generator will use the utility’s grounding conductor. So there is no need to ground the generator separately. However, if you’re using a floating neutral conductor, you will need to use a grounding rod.

  • Situation 2

Your Generator’s Non-Current-Carrying Metallic Do Not Have Bonds To The Frame. This isn’t going to be a common complaint. That’s because most modern generators aren’t built this way. But if the generator’s manual says that it is built in such a manner or if you can see that it’s built this way, you should ground your generator properly. 

However, if it’s difficult to ascertain, we would suggest consulting a professional.

  • Situation 3

You have a floating neutral generator, and you use it to supply electricity directly.  Usually, the use of floating neutral generations isn’t supplying power directly. But in exceptional circumstances where there is a direct connection between a floating neutral generator and an electrical appliance, you should ground your generator.


FAQs

2. What happens if don’t ground my generator?

Risks of not grounding your generator include

  • Generator and appliance overheating 
  • Wiring damage
  • Damage to appliances
  • Household fires
  • Electrical shocks or electrocution 

2. Do I Need to Ground My Generator Myself?

Nope. If you don’t have professional training, don’t deal with electricity. The reason is: it isn’t worth saving a few bucks over this kind of risk. 


Closing Thoughts

So, to put it in a few words, the answer is yes under the following conditions. Firstly, if you’re using it to supply your house through the house’s supply board, in the case of a bonded neutral generator, you should ground it with a grounding rod. On the other hand, if you are using a floating neutral generator, you should only switch the live wire via the transfer switch. 

Secondly, you should ground it if there isn’t a proper bond between the non-current-carrying metallic parts and the generator frame. Lastly, you would need to ground it if you’re using a floating neutral generator, and it supplies electricity directly to your electrical appliances.

Leave a Comment

Share via
Copy link
Powered by Social Snap