Portable Generator Transfer Switch: How to Install a Manual Transfer Switch

Whether power outages are common or irregular in your area, there is no reason to stay in the dark and helplessly wait for the power to come again. A portable generator will be one of the best alternatives for you to have backup power. Sometimes you need to install a transfer switch to your portable generator. In this article, we will learn how to install a portable generator transfer switch manually.

Why A Generator Needs A Transfer Switch?

A portable generator is a great way to provide you backup power for most of your home appliances and electronic devices. But the question is why your portable generator needs a transfer switch. Some of the main reasons for which you need this are mentioned below:


Portable Generator Transfer Switch


  • According to the law of the generator systems in all states, as per the mandate of the National Electric Code, you must install a transfer switch.
  • A transfer switch helps you toggle your main home power to your generator backup power, and thus it reroutes your power supply.
  • It protects repair workers in the event of a power surge that may occur from your generator.
  • A transfer switch also ensures the overall safety of your power supply system.
  • It provides power to specific appliances through specific switches.

How To Install A Manual Transfer Switch?

Below is the step by step instruction to install your portable generator transfer switch:




Step 1:  First of all, you have to switch off your main power grid system from your home electrical service panel. You need to be careful while doing this as the terminals still get energized.

Step 2:  At this step, you need to determine what are the most important household circuits in your home. These are things that you use in an emergency when there is any power outage. Generally, the most important household appliances are lights, fans, freezer, refrigerator, furnace, and some other necessary things.

Step 3:  Now, you have to match all your crucial circuits with the circuit inlet. You will get all these on your pre-wired transfer switch. It will be great if you can balance the load in your transfer switch as perfectly as it was initially. Suppose your freezer is on the rightmost switch circuit, you should try to connect your refrigerator to the circuit that is on the farthest place to the left.

Now, the double-pole circuits will need two 120 V of circuit connections. You also keep in mind that you don’t mismatch the 15-amp and 20-amp circuits with one another.

Step 4:  After that, you need to choose and remove a knockout at the endpoint or bottom of your main electrical service panel box. You need to ensure a properly sized knockout to match the connector. It will be on the comfortable conduit that is coming from the transfer switch.

Step 5:  Now, you have to give the connection to the wires from your transfer switch into the hole knockout. You should be careful not to damage the insulation while doing this. You see that all the cables are labeled with maintaining the serial of the circuit in the switch box.

Step 6:  After completing the above steps, you should secure the flexible conduit using a locknut and a bushing, if necessary, from the switch box of your main service panel. Then it’s time to attach the box of your transfer switch with the wall in a way that its closer edge is approximately 18 inches away from the main service panel center point. Based on your wall type, you can use any connector.

Step 7:  At this step, you are good to remove the breaker from your main service panel box for the first critical circuit. Then you need to disconnect the hot wire that comes from a specific part of the breaker.

Step 8:  Now, you have to find out the red wire that correlates with the circuit you have disconnected. Then link the red with to the breaker that you removed a moment ago. After you complete everything, you have to reinstall the breaker.

Step 9:  As you have found out the red wire earlier step, now do the same to the black wire from the same circuit of the transfer switch. Then using a yellow wire connector, crumple these two wires together with the old feed wire. Now, twitch the wires cleanly from the way at the edges of the transfer switch box. Then do the same for the next circuit and continue the process.

Step 10:  If there is any 240-volt circuit is a critical circuit, you have to attach the red that directs from the two circuits of the transfer switch to the double-pole breaker. The two circuits that come from the transfer switch should remain one after another. Their switches should also stay connected with a handle tie.

Step 11:  After making all circuit connections, you have to attach the white wire meaning the neutral wire, to the neutral bus bar opening of the main power panel from the transfer switch.

Step 12: Now, you need to link the green ground wire to an open port that is on the grounding bar in your main power service panel from the transfer switch.

Step 13:  After completing everything above, it’s time to test the transfer switch after ensuring you have set all of the switches to the LINE setting. You should still turn off the power from your main power panel breakers. It’s also essential to operate and install your generator properly and professionally.

Step 14:  Before you turn the generator on, you need to attach the power cord. You can do this from the generator to the switch box. You should not attach and even detach a generator cord while you are running your generator. You also switch on your standby generator and allow it to run for one or two minutes.

Step 15:  Finally, you have to overturn each circuit switch on your transfer switch box to the GEN position at the same time. You are maintaining the balance by operating back and forth from circuits on the right and left side. It’s prohibited to turn all circuits on all together at the same time. You should try your best to keep the wattage levels in balance.

How Does A Transfer Switch For A Generator Work?

The working procedure of a transfer switch is as following:


How does a transfer switch for a generator work


A transfer switch is such a device that separates selected circuits and then offers “Break” and then “Make” switches. Every switch comes with 3 different positions, such as LINE, OFF, and GEN. For the line position, your utility power feeds the selected circuits. For the Gen position, some specific circuits get power from your generator. And when you switch from line to gen, you pass the off position. Because of this, a positive break occurs that prevents any unexpected incident.

Frequently Asked Question

Do I need a permit to install a generator transfer switch?

Yes, according to the law, you need a permit to install a generator transfer switch.

Can I install a generator transfer switch myself?

It’s always better to install a generator transfer switch by a licensed electrician. However, you can also install the switch.

How far can a generator be from the transfer switch?

The maximum distance of your generator from the transfer switch is 75 feet.

Can you use an automatic transfer switch with a portable generator?

Yes, there is no problem with using an automatic transfer switch with your portable generator.

Listen From An Expert On How To Install A Manual Transfer Switch


Final Thought

You should use a portable generator transfer switch not only to obey the state rule but also to secure your power connection system. Installing a transfer switch will be very easy if you follow the instructions that we have provided above. There is also an automatic transfer switch that you can install to your portable generator.

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