Mobile Home Grounding & Electrical: 6 (Safety) Issues Explained
Electricity powers modern living; when you move into your manufactured home, you expect to switch on the lights, watch TV and run your appliances with the same carefree approach as if you were living in a site-built home.
Are the grounding and electrical systems in a mobile or manufactured home identical to a traditional home?
The Installation and Safety Codes
Your mobile home grounding and electrical system are heavily regulated and wired to the same exacting standards as any traditional house.
The relevant regulations are the HUD code (the regulatory bible for manufactured homes) and the National Electrical Code (NFPA 70, ANSI C-1).
Plus, local state rules may exceed these minimum standards for electrical safety in mobile homes.
Essentially all home electrical systems are safe to operate, and repairs and additions need a qualified professional.
1. Electrical Power Supply
If you buy your electricity from the grid, your home connects to the power transmission network.
The site generating the electricity that powers your reading lamp can be hundreds of miles from your home.
A stepdown transformer lowers the voltage before feeding it through a meter and circuit breaker system to power your home through your electrical wiring circuits.
This process is identical in site-built homes and conventional homes.
Suppose you generate your electricity from solar panels in whole or in part (off-grid). In that case, your electrical set-up takes the electricity generated by your solar panels and transforms it into a useable form, and typically stores it in batteries until you need to use it.
Again, this process is identical in all types of housing.
Mobile home parks are ready for you to connect to the grid through the existing infrastructure available on site.
Installing your mobile home on a plot of land without this infrastructure means contacting a utility company and putting in the infrastructure to connect to the power supply. The further away you are from the closest connection point, the more you pay to access power.
On undeveloped land, many people opt for an off-grid power solution.
You can use a generator to power your mobile home, but these tend to be expensive to run for fuel costs, and most people use a generator as an emergency backup for other supply options.
Your power supply needs to provide enough energy to meet your power needs. If you can’t access the appropriate amount of power, you can have energy efficiency problems and potential motor burnouts.
Plus, you can’t run your appliances, and the fridge will heat up, spoiling your food.
If you want to calculate your energy usage, you can work it out manually or use an online calculator (link below).
The amount of energy you use in your mobile home depends on your activities – people, not homes, use electricity.
Some modern manufactured houses come with energy star certifications for energy efficiency and will cost less to run than other models.
2. Grounding Systems
Since 1960 an awareness of electrical safety means all homes must be grounded.
A grounding system protects the homeowner from power surges and excess electricity. If a house is not grounded, you can get an unpleasant shock from items like the refrigerator or other metal components.
Grounding provides a safe path for stray voltage to enter the ground through a recognized route instead of jumping through a human body or discharging as a spark.
A mobile home must be grounded through an electrically isolated grounding bar when connected to an electrical power supply. Therefore, the grounding system is a fail-safe system.
The electrical circuits in your home operate by powering your appliances through the active wires and returning excess electricity through the neutral wires.
The grounding bar only comes into play if your circuits fail somehow and potentially transfer electricity outside of the electrical circuits in your home.
The grounding system catches and disperses the stray electricity harmlessly into the ground beneath your home.
3. Electrical Distribution Panel
Four conductor wires enter your manufactured home (instead of the customary three). Color-coded:
- White is the neutral or return.
- Green is the ground.
- Black/Red or white with black or red tape are the live wires.
The neutral and ground wires remain isolated from each other in the home and out towards the utility connection.
Grounding through the hitch caster or metal stabilizing bars is not approved and is unsafe.
The approved method is through an electrically isolated grounding bar located in your electrical distribution panel. Every metal item (not carrying current) in your mobile home grounds through this bar.
4. Electrical Circuit Breakers
Electrical circuit breakers are the modern solution to protecting your appliances and mobile home from potential damage through excess power fluctuations.
These devices are resettable fuses that automatically switch off the power in a circuit if the current exceeds a safe level.
Instead of a thin wire fuse (one use only), it contains a bimetallic strip or an electromagnet depending on the design.
If the current rises above a safe level, the switch trips and shuts down that circuit.
5. Ground Fault Circuit Interrupter (GFCI)
These are upgraded circuit breakers that act to protect you from damaging shocks.
The GFCI monitors the hot and neutral wire – the current in each is generally at the same level.
Suppose there is a difference – the GFCI switches off the power in that circuit. The GFCI reacts faster because it does not wait for an unsafe current level before acting – this process is safer for you.
Typically, your mobile home will have GFCI outlets in your kitchen and bathroom as these are super safe for you in operation.
6. Warning Issues for Electrical Problems
Electricity is an excellent resource but potentially hazardous, so be alert for potential signs that something may be wrong with your mobile home electrical circuits.
Typical signs that you may have a problem are:
- Warm, buzzing, sizzling, or sparking outlets.
- Loose outlet covers.
- Broken switches.
- Outlets with no or spotty power.
- Frequent tripping of the circuit breaker.
- Hot electrical smells from the breaker or outlet.
- Flickering lights.
- Rodent droppings – can indicate potential chewing of cables.
Use a professional electrician to remedy any electrical faults because you and your family need your electrical circuits to operate safely.
FAQs About Mobile Home Electrical Safety
These are the questions that keep mobile homeowners up at night.
Can Lightning Strike a Mobile Home?
Lightning strikes the earth to ground the strong charge built up in the clouds and can hit during thunderstorms, volcanic eruptions, intense firestorms, and nuclear explosions.
Most people experience lightning as part of a thunderstorm.
Lightning usually strikes the tallest object in an area, which is why you don’t stand under a tall tree in a field in a thunderstorm.
Although lightning typically takes the easy path to the ground through the tallest object, it can strike anywhere. That means your mobile home can get hit by lightning. But it is unlikely in most areas.
Provided your mobile home is grounded (necessary to be HUD compliant), the lightning will discharge through the grounding bar without harming you and your family.
In fact, if you are outside and there is a risk of a lightning strike, get inside your mobile home because it will be safer for you.
A sensible precaution in any home during a thunderstorm with a risk of a lightning strike is to avoid handling water, touching metal objects, or using electronics.
Lightning can strike any home, and mobile homes are not at increased risk of a bolt from the sky.
If you live in a region with severe storms and the risk worries you, you can invest in specialist lightning protection systems. But the standard grounding system and circuit breakers in your home are adequate protection in most cases.
Does a Mobile Home Frame Need to be Grounded?
As explained in the grounding systems above, the entire mobile house needs to be grounded as a safety feature.
A grounding system is a backup measure to catch stray electrical currents before they can harm you or your appliances.
How to Ground a Mobile Home Frame?
The mobile home frame and other non-current bearing structures ground through an electrically isolated grounding bar.
The grounding bar connects your home to the ground by providing an easy path for stray electric currents to follow.
The grounding bar installation is part of setting up your mobile home on a permanent site.
Can Mobile Home Feeder be Direct Burial?
How you connect to the utility network for electricity depends on the infrastructure available in your area. You can connect to a utility pole or through underground cables.
The connection to your mobile home is underneath and through an electrical control panel with a meter and circuit breakers.
If you have ground-based solar panels or a generator supplying your electricity, you can bury the cables underground if you follow appropriate safety regulations.
A typical mobile home feeder wire uses stranded aluminum alloy conductors and has superior weather resistance, abrasion resistance, crush resistance, sunlight resistance and is suitable for wet or dry environments as well as direct burial.
You expect it to be RoHS compliant and RUS accepted.
Can Mobile Home Feeder be Run in Conduit?
Conduit protects wiring from mechanical and other damage. You use conduit wiring for exterior and interior purposes.
Your mobile home installer will explain the best conduit for your climate and installation type.
Does Mobile Home Feeder Wire Need Conduit?
Typically state and HUD code regulation will expect your mobile home feeder to run in conduit to protect the electrical wires from hazards such as wet ground or mechanical damage.
How Far Can You Run Mobile Home Feeder Wire?
The feeder wire runs from the service pole or connector to your mobile home. The HUD code specifies a maximum distance of 30 feet from the mobile home to the service pole.
Do Mobile Homes Have Fuse Boxes?
Fuse boxes are old-school electrical circuit breakers – blow a fuse, and you need to replace it. Instead, modern homes opt for reusable circuit breakers that you can reset after the circuit blows.
Mobile homes have the same electrical protection as site-built homes, with a circuit breaker panel replacing the fuse box.
Do Mobile Homes Have Different Electrical Outlets?
The outlets in your mobile home match the plugs on your appliances and are the same as the types of outlets found in traditional houses.
There are nine basic types of outlets:
- 15A, 120 Volt outlet – three-pronged, cheapest on the market, and only suitable for light home use.
- 20A, 125 Volt outlets – best for larger appliances found in kitchens.
- 20A, 250 Volt outlet – heavy power use.
- Tamper-resistant outlets – prevent accidental entry of a fork or pencil, best if you have kids.
- GFCI outlets – bathrooms and kitchens.
- AFCI outlets – prevent problems with electricity arcing.
- Switched outlets – you can turn the power off without unplugging the appliance.
- USB outlets – plug your electronics in with a USB connector to charge your phones or laptops.
The outlets you have in your mobile home depend on what you specify, and you can opt to upgrade and change with the aid of a qualified electrician.
Can You Use a Generator for a Mobile Home?
Any home or building can use electrical power supplied by a generator either as the primary or alternative power source.
What Size Generator to Power a Mobile Home?
The size of the generator depends on how many appliances, lights, and other devices you need to power with that generator.
One person’s electrical needs can be significantly higher than another.
Use an online calculator to guide you to the correct size of generator for your mobile home.
How to Hook Up a Generator to a Mobile Home?
You need to use a legal wiring system to plug your generator into your mobile home. You must consult your local state regulator because the rules can vary markedly.
Typically, you get a professional electrician to install a manual transfer switch so you can opt to connect your mobile house to the grid or your generator with the flick of a switch.
Why Put Tires on the Mobile Home Roof?
Perhaps a well-meaning relative or neighbor has said you should put some rubber tires on your mobile home roof as a precaution?
Exactly why are they suggesting that?
What does placing rubber tires on your mobile home roof do for you?
This advice comes under the heading of one of those bits of folk wisdom that may or may not be valid or useful.
- Protection against lightning – nope, it has no impact whatsoever on protecting your home from lightning.
- Weighs down the house in hurricanes – mobile houses in hurricane-prone areas are built and tethered to survive; popping a loose tire on top may result in the tire blowing off the roof and injuring you or a neighbor.
- Stops the wind from lifting loose sheets on the roof – if you have an issue with storm damage and need to hold down temporary sheeting before you can repair your roof, a tire is a good weight. A tire may be easier to get hold of than a rock in some areas.
- Stops roof rumble – metal roofs can resonate in the wind and flex under heat. The movement of the metal sheets is noisy and known as roof rumble. Putting weight on top can deaden or eliminate the roof rumble, which may be why some mobile homeowners put tires on roofs.
Of course, people may put tires on the roof in rural areas because it is a convenient place to stash them, rather than for any practical purpose.
Finally
A HUD code mobile home installed by professionals will have a safe and effective electrical system.
You can sleep safely at night knowing that you will be alright in the unlikely event your mobile home gets struck by lightning – even if you don’t have tires on the roof.
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