Off Grid Ham: Transfer Switch

Transfer switch. original photo ©2021

Chris Warren of Off Grid Ham talks about generators and the Transfer Switch.

Transfer switch 101.

Have you ever wanted to run more than just a few devices from your generator? Maybe you want the convenience and safety of connecting your existing home AC wiring to an off grid source? Maybe you don’t like the idea of running extension cords all over the house? Most gas generators can do much more than power a few radios. A transfer switch is the safest and best way to get power to where you need it.

A transfer switch is permanently installed in a home or other structure. It allows you to switch between commercial grid AC power and a backup source. AC outlets, lights and appliances connected back to the transfer switch will then work normally. You do not have to run temporary cords or physically disconnect and then reconnect individual devices.

What happens inside the box.

The internal functioning of a transfer switch is fairly simple. A switch allows the load to be connected to either commercial AC power, or the backup source. It will never allow both at the same time. Some versions are actually several small transfer switches that move individual circuits between power sources. Retailers also offer transfer switches that automatically move the load from main to backup power when the main power fails.

transfer switch original graphic ©2021

Choosing a transfer switch.

Wow, there are a lot of choices out there! Very basic manually operated switches sell for under $150.  Automatic switches with internet connectivity can go well past $1000. For my own home, I went with a Reliance Controls 30216A. It can transfer individual circuits and includes watt meters for load balancing. Reliance Controls is probably the most popular switch on the market; they are available almost anywhere. I’ve had my switch in service for about ten years with excellent performance.

The Reliance 30216A and others like it come with an added bonus. Because it switches individual circuits, there is no need to disconnect the main feed to your house. This design feature makes installation barely more complex than changing a breaker.

Another factor to consider is materials needed to install your transfer switch. Reliance Controls sells their products as a kit. You get everything you need, including a cable to connect your generator. If you go with the cheapie $139 switch, you’ll have to buy extra items to make everything work. When you add everything up, expect to spend at the low end $300-$500.

The 240 volt question.

Most mid-sized and up generators have a 240 volt outlet that will connect to your transfer switch. So what do you do if your generator does not have a 240 volt outlet? This is common on smaller generators, such as the immensely popular Honda eu2000i. I located adapter cables for sale on line, but they are rare. Finding one that’s compatible with your application might be difficult. The other option is to make your own cable.

Using a converter cord I made myself, if needed I can connect any 120 volt generator to my 240 volt transfer switch. Making your own adapter is actually super-simple but dangerous if you mess it up. Since the safety consequences of doing it wrong are so serious, I decline to give instructions on this blog.

The photo below is my converter cord. The two standard male 120 volt connectors plug into the small generator. On the other end is a female L-14-30 plug that goes to the transfer switch. Keep in mind that you still cannot exceed the capacity of the generator.

transfer switch original photo ©2021

Safety considerations.

To say the least, installing a transfer switch is not for beginners. Having a thorough knowledge of home electric systems and being confidant working near exposed live conductors is an absolute must. There are many instructional YouTube videos, but not all of them give good advice. If you have even the slightest doubt about your abilities, listen to that inner voice and get competent help even if you have to hire a pro. I did my own work, with a skilled assistant, and it took a weekend. This included cutting a wall open, cosmetic finishes, and running 40 feet (12 meters) of wire to a new generator tap on the outside of my house. Simpler installs can probably be done in one day.

When operating your generator, always have a fire extinguisher nearby. Always run the generator outdoors (not in the garage, even with the door open). Always have working carbon monoxide detectors in your home.

The internet is full of dubious tricks to connect a generator to your home wiring. Some hacks involve clamping automotive jumper cables in your breaker box. Others employ a “cheater cord”: a cable with a male AC plug on both ends. All of these lame ideas are dangerous and illegal. Don’t play games; do it right. If a dumb shortcut results in property damage or personal injury, you could find yourself on the wrong end of a lawsuit. Your insurance carrier may not help you either.

Code compliance & permits.

Building codes and ordinances regulating transfer switches vary by locality. You may need a permit, depending on where you live. The National Fire Protection Association document NFPA-70 is the nationwide standard for all electrical work. Many state and local governments have codes that are stricter than what is in NFPA-70. Do your due diligence!

In general, you need a permit if your proposed off grid system meets one or more of the following criteria:

  • The backup generator or power source is greater than 15 kilowatts.
  • The generator starts and transfers the load automatically.
  • Your generator is permanently wired to the transfer switch.
  • The generator is fueled by commercial natural gas or a non-portable fuel tank (this would include large propane tanks).
  • The generator itself is permanently mounted/not portable.

Also, generators greater than 15 kW require a manual disconnect “easily visible and accessible from the generating device”. In some situations more than one disconnect is required (NFPA-70 445.18, 445.18D, 702.12A). Generators less than 15 kW do not require a manual disconnect (NFPA-70 702.12B). Wiring to the transfer switch and all related conductors must be rated for 115% of the maximum power capacity of the generator (NFPA-70 445.13).

In most situations, generators less than 15 kW that are not permanently wired and are started/transferred manually do not require a permit. This would cover most applications an off grid ham would encounter.

I must stress again that these are general guidelines. Your locality can and probably does have different and/or more rigorous standards.

Load balancing.

If your generator has a 240 volt output, keep in mind that it’s two 120 volt AC sources combined. The generator achieves this by spinning two separate coils that produce 120 volts each. The off grid ham must be careful not to overload one side of the generator while placing little or no demand on the other.

On most consumer-grade generators, the total rated output equals the sum of the two 120 volt sections. In other words, your “7000 watt generator” is really two 3500 watt generators integrated into one physical unit. Therefore, you cannot pull more than half of the total capacity from either side of the generator.

With a transfer switch load balancing is somewhat simplified. Each half of the 240 volts is directed to its own side of the switch. All you need to do is assign your loads evenly between the two sides. In the photo of my Reliance switch above, notice that it is divided into two banks of three circuits each, A-B-C and D-E-F, with corresponding watt meters.  When I’m on my 5000 watt generator, I must not exceed 2500 watts on either side.

The 120 volt standard outlet on the front of your 240 volt generator is probably split internally so each plug is wired to a different coil. This allows you to tap both coils for load balancing, but do not pull more than 50% of the total from either plug.

When installing your transfer switch, be careful not to assign all your high power demand circuits to the same side of the switch. Distribute them as equally as possible between both sides so you’ll get the most benefit from your generator.


Here is a link to the complete NFPA-70 document (free registration required).

Reliance Controls makes some excellent transfer switches. Their documentation is top notch and they even have instructional videos with accurate information.

This very cool website gives a concise listing and specifications for numerous AC plugs used with generators and transfer switches.

This Off Grid Ham article from April 2018 discusses NFPA-70 in detail.

Backdoor Survival: Going Stealth When Using a Generator

Going Stealth When Using Generators: Lessons From Venezuela comes from Jose Martinez in an article at Backdoor Survival. Jose Martinez was able to flee Venezuela and make a life elsewhere, but shares what he learned in the chaos in various articles.

…This long introduction is only meant to open your eyes so you can understand the attitude and behavior of the people who very likely will be roaming in the streets after or while the collapse is occurring. There will be some pockets where the situation won’t be that bad, but won’t be too many, and perhaps far away from each other. More about that in the next articles.

Not all of your neighbors may be good.

Let´s go on topic now. I´m sure there is plenty of preppers around there with generators and a huge fuel tank. Many of us even with a propane system as a backup. Great. We all agree that, under some type of threat, and the power grid is shut down in our nearby area, we´ll turn on our generator, and start to count how many hours it´s on, and check the fuel level every few hours.

Hopefully, you´ll have a battery rack large enough to have some lights and heating on for a while, when the generator is off to save fuel. It should be possible to replenish the tank, after all. This will depend, of course, on every different situation. I know something for real: we can´t prep for everything.

But we can prepare for some general situations that are going to generate some type of scarcity. The difficult part here, and I speak from my own experience, is the calculation of how much time that contingency is going to last.

We were more or less prepared for civilian turmoil and general disorder that could make us bugging in. Time proved us wrong. Dangerously wrong. I´ve mentioned this in other articles, though. Let´s keep going with this…

It´s astonishing to learn how silence can rule over the land when there is no electricity. When we were still living in Venezuela, the worst of the blackouts (even for me, a lover of peace and quiet) was the silence. It was good for some purpose, though, because sometimes it would allow to detect early presence of undesirable or threatening individuals, like those running in small Chinese motorbikes all over the place, with two guys, the one in the backseat generally armed with a 9mm or a .38 revolver. Those would rob everyone within their reach.

Once a small engine motorcycle is detected, everyone looks for getting out the way in Venezuela. If your generator is too loud, you won´t hear inside your home what can be happening outside, and we can’t be monitoring our CCTV surveillance cameras (and if you don´t have them, get them. Now, when they´re on the cheap, and PLEASE conceal them. Don´t be a smart a$$ and leave them in the open as a “deterrent” to someone knocks them down with a silenced .22 and blind your eyes outside). If you are nearby the sound source it´s very likely you won´t be able to hear anything going on around. This is a very powerful reason to think carefully about where we put money in. There are quite expensive generators, liquid-cooled, where the coolant act as a soundproof layer, and with specially designed casings to quieten the sound. Of course, you can imagine how expensive these machines are. They worth it, though, for those who can´t or won´t bug out to a secluded location and prefer to stay put in their place. I can accept that…

Organic Prepper: How to Deal with Rolling Blackouts: Notes from South Africa

In this article from the Organic Prepper, a South African writes notes about dealing with rolling blackouts and alternate forms of power like generators and solar power. It has some good information on battery cycles and reducing your loads. While I haven’t seen as much damage to equipment from power outages as the author of the article, it does happen. Some power utilities will help you put in a whole house surge suppressor. Our local utility will put one in at the meter for around $6 per month charge.

Living in South Africa we have had our share of rolling blackouts nationally. The cause: nefarious activities. The result being us forced to find ways to ensure we are not affected as badly.

The problem is better now, but it has highlighted that it is not just a South African problem, but in actual fact a Western world problem. We all are totally reliant on a massive aging infrastructure that can come tumbling down like a house of cards, with or without help.

Another problem is the cost to keep the national system operational. In some areas, it is not a priority to resolve the regular failures.

For getting started with backup power, remember that NEEDs vs WANTs –  a huge price difference.

  • UPSs – with like 2 up to 8 100ah batteries. Good for a number of hours depending on use – most cost-effective solution
  • Generators – works for some, but cheap ones cost more as they damage some electrical appliances over time.
  • Solar inverters and panels – power failures, what is that? And you save a lot of money afterward IF YOU DO IT RIGHT.

What is also good to know, when the power goes off, switch off your distribution board, leaving just the light plugs on. When the power comes back on, lights come on, wait a few minutes for the grid to stabilize, before switching things on. We have lost computers, internet modes, freezers/fridges, alarm systems etc, damaged when the grid goes off and back comes on. UPS’es have the best protection for this.

How does one solve the issues from frequent blackouts?

Here are some pertinent notes from my own experience.

  • Older fridges/freezers have a huge start-up current, necessitating a bigger inverter and they use a lot of kWh over 24 hours. Upgrade them to an A++ or even A+++ model, as soon as you can. It will save you on utilities and can be powered longer on batteries.
  • Lights: obviously CFL and / or LED, and not cheap LEDs. They are cheap for a reason. Test the wattage, it may be more than the claimed wattage “saving” you nothing. Check the claims lumens.
  • Putting lights on solar is not a “savings”. It is actually an increase in cost for batteries are more expensive per kWh than utility power costs per kWh because lights are use when there is no solar power. So switch to the best lumens for the lowest watts, and switch the light off when not in use, biggest saving ever.
  • Stove/oven/kettle – entire kitchen – on solar power is doable, but expensive. Utilities are cheaper. Kettle take few minutes to boil, microwave also a few minutes, why spend more on inverter and batteries to power them. Use gas. Gas per unit of power may not be cheaper than utilities. Check what you are paying for each.
    Maximum savings are: Switch off at the wall, not in standby, for all the standby power adds up to a lot of power paid for, yet not used.
  • When all the occupants of a house are asleep, say 11pm – 5am – how much power is used during that time? Excluding alarms and outside lights – which have a motion sensor to switch on. Figure this out and find places to cut.

The Rules of Running Backup Power Efficiently

Right, now that you have a few notes to consider, here are the rules that we have found important when using backup power like a generator.

The very first rule: NEEDs vs WANTs

Needs are much cheaper than wants, like you WANT to power your entire house during a power failure, or do you just NEED to power very selected devices like a fridge, lights, cell phone chargers?

The second rule: Know your loads and runtimes and match the batteries to that…

Click here to continue reading at the Organic Prepper.

Off Grid Ham: Grounding Your Off Grid System

Chris Warren over at Off Grid Ham has a nice article about the often confusing concept and execution of system grounding in Grounding Your Off Grid System. He’s not just talking about grounding your communications gear, but also your solar panels, and generators. Don’t get burned; learn to ground.

It’s hard to follow.

One issue that seems to come up a lot in the off grid radio realm is proper system grounding. The rules and expectations are hard to follow. There are a lot of opinions out there. Many of them are accurate, others are not. Today we’ll go over some basic grounding principles for off grid ham radio. This is by no means a comprehensive guide.

All the same basic grounding concerns with commercial power also apply to off grid energy. Electricity does not behave differently just because it comes from a renewable source. Finally, lightning does not discriminate!

What exactly is “ground”?

In the most simple terms, “ground” is a reference point. If you remember your basic electricity training for your amateur radio license, voltage is an expression of potential energy. However, potential doesn’t mean anything unless it is compared to something. For example, if you are standing on the roof of your house you have potential energy (via gravity) when compared to your yard. If you are laying flat on your back in your yard you have no potential energy compared to the yard because, after all, you’re already in the yard. You can’t fall if you’re already down, right?

Electrical grounding works the same way. Electricity needs a place to go, and it will not go anywhere without potential. Ground provides an electrical reference point. This has many implications for the operational effectiveness and safety of your off grid system.

Grounding outdoor equipment.

If electricity needs a place to go, it’s best for it to have a defined safe path instead of letting it find its own way. Off grid hams should place a high priority on grounding antennas and solar panels.

Connect (bond) solar panel frames together with 6 gauge copper wire attached to a conductive metal pipe or rod pounded into the ground. Be sure also to connect any metal support structures. Grounding lugs made specifically for solar panels are available from many sources including (of course) Amazon. Ground rods should be at least six and preferably eight feet deep. Getting a ground rod down that far will be a problem for many hams. You can substitute two or more shorter rods in place of one long one (be sure to bond the rods to each other).



Click here to read the entire story at Off Grid Ham.

Honda Recalls Some 2200 Generators

From the Consumer Protection Safety Commission:

Name of product:
Honda EU2200i, EU2200i Companion and EB2200i Portable Generators
The portable generator can leak gasoline from the fuel valve, posing fire and burn hazards.
Recall date:
March 20, 2019
About 200,000
Consumer Contact:

American Honda toll-free at 888-888-3139 from 8:30 a.m. to 7 p.m. ET Monday through Friday or online at and click on “Recalls and Updates” at the bottom of the page for more information.

Recall Details


This recall involves Honda EU2200i, EU2200i Companion and EB2200i portable generators. The recalled portable generators were sold with a red or Camo cover. The names “HONDA” and the generator model name are printed on the control panel. The serial number is located on a lower corner of one of the side panels of the generator. The following model numbers and serial number ranges are being recalled:



EB2200iTA EAJT-1000001 EAJT-1005474



EAMT-1000001 EAMT-1260796

Consumers should immediately stop using the recalled generators and contact a local authorized Honda Power Equipment service dealer to schedule a free repair. Honda is contacting all known purchasers directly.


Honda has received 19 reports of fuel leaking from the fuel valve.  No injuries have been reported.

Sold At:

Authorized Honda Power Equipment Dealers and The Home Depot and other home improvement stores nationwide and online from February 2018 through February 2019 for about $1,100 to $1,300.


Thai Honda, of Thailand


American Honda Motor Company Inc., of Torrance, Calif.

Manufactured In:
Recall number:

Champion 7000/9000 Generator on Sale at Costco

Costco in Kennewick is currently having a sale on the Champion Dual Fuel 7000 watt generator. This generator sold for $799 a couple of years ago, and currently sells for $699 on Costco’s website.  In store, it is on sale now for less than $550.

Nov. 2019 Edit: I notice that a lot of people are still hitting this post from the summer of 2018. I haven’t seen this model at Costco for several months, now. It seems to have been replaced by the Firman dual-fuel generator (10k/8k gas, 9k/7.25k LPG) which is a higher priced generator.

The Champion Power Equipment 100419 7000-Watt Dual Fuel Portable Generator is the perfect combination of versatility and convenience. Whether you need power for your home or next project, Champion Power Equipment makes powering your life more convenient than ever.

The convenient electric start includes a battery, plus Cold Start Technology ensures a quick start in cold weather.

Easily monitor power output and track maintenance intervals with Intelligauge, which allows you to keep track of voltage, hertz and run-time hours. Designed with a low oil shut-off sensor, this unit includes 1.2-quarts of 10W-30 oil.

Operate your Dual-Fuel generator right out of the box on gasoline or propane, and easily switch fuels with our patented fuel selector switch that allows for safe switching between fuel sources.

Using gasoline, the 439cc Champion engine produces 9000 starting watts and 7000 running watts, and will run for 11.5 hours at 50% load when the 8.5-gallon fuel tank is full. It produces 8100 starting watts and 6300 running watts, and will run for 5.5 hours at 50% load when using a 20-pound propane tank. Also included is a 3.3-foot propane hose with a built-in regulator.

With a noise level of 74 dBA from 23 feet, which is a bit louder than a vacuum, this machine can provide home backup in an outage, plus the Volt Guard™ built-in surge protector prevents overloads and keeps your equipment safe.

All the outlets have covers and include a 120/240V 30A (L14-30R) locking outlet and four 120V 20A GFCI protected household outlets (5-20R).

Champion’s thoughtful packaging and clear directions make setup hassle free, plus the foldaway U-shaped handle makes it easy to store, while the never-flat tires in the included wheel kit make transport a cinch.

Buy this EPA certified and CARB compliant generator with confidence – Champion Support and our nationwide network of service centers will back up your purchase with a 3-year limited warranty and FREE lifetime technical support.


  •  Dual Fuel – Operate your 7000-watt portable generator right out of the box on either gasoline or propane, plus the unit holds 1.2-quarts of oil (included) and has a low oil shut-off sensor
  • Electric start – Power up the 439cc Champion engine with the handy toggle switch, battery included
  • Intelligauge – Keep track of voltage, hertz and run-time hours to easily monitor power output and track maintenance intervals
  • Powerful – At 9000 starting watts and 7000 running watts on gasoline and 8100 starting watts and 6300 running watts on propane, trust Volt Guard™ built-in surge protector to prevent overloads
  • Champion Support – Includes 3-year limited warranty with FREE lifetime technical support from dedicated experts

Items Included: Smart Charger, Engine Oil, Wheel Kit, Oil Funnel, Propane (LPG) Hose, Battery