How to Make a 30-Amp Generator Extension Cord

RVs are equipped with all kinds of necessities one needs for a peaceful vacation. From the refrigerator to the TV, there is nothing that a modern RV doesn’t offer. However, to power, all this equipment one needs a reliable source of power from outside. Once you have figured out a power source, the next task is to connect it to your campervan. Connecting may seem like a simple task, but it really isn’t, especially once you have considered all the factors. Such complications should be kept in mind to ensure a foolproof connection.

Why Make an Extension Cord by Yourself?

To begin with, not all extension cords are created equal. Conventional extension cords are different from the ones used with generators. They are designed and made keeping in mind the intense conditions they will endure. There are many extension cords available in the market but if you want the best possible result, we suggest you make one for yourself. Making a 30-Amp extension cord isn’t a big deal. Only some basic technical know-how and the required tools are needed, and you’ll be all set to make a great generator extension cord for your RV.

Important Considerations

Before diving into the details of making a 30-Amp extension cord, it is important that we discuss some technicalities. The first is to decide the length of the cord. The short answer to this is to keep the length as precise as possible. This is because the more you increase the length the greater the line losses there would be. The inadequate power supply, as a result, would damage appliances. In severe cases, it can short circuits which can very quickly become a fire hazard. Though, this doesn’t mean you should get a wire that would barely reach its destination. In case a longer wire is an absolute necessity, you would need to cut or limit power usage.

Extension Cord for a Mid-Size RV

A 30-Amp extension is an established gold standard for mid-size RVs. Medium-size RVs have relatively lower load requirements for which a 30-amp cord is enough. Since most campers are mid-size, therefore, 30-amp cords are the most common size. For a 30-amp extension cord to handle 3,600 Watt, it is necessary for it to have a 30 AWG. The AWG is the U.S standard for wire gauges and stands for American Wire Gauge. AWG has an inverse relation with wattage. Greater the wattage requirement, the lesser the AWG should be. For longer distances, the AWG or gauge should be lower. For instance, a 25-ft long 16-gauge cord is good for 13 Amps, whereas a 25-ft long 10-gauge cord is generally rated for 25 Amps.

Required Tools

Before venturing to make a generator extension cord, you will need to make sure you have the necessary tools. There are good chances that many of the required tools mentioned below would already be in your possession:

Paper cutter
Electrical tape
Male Plug
Square box with a cover
Strain relief box connector
Fuse (compatible with 30-amp current)
Extension Cord
Two receptacles

Making a 30 Amp Generator/RV Extension Cord

  • After collecting all the tools, the next step is to make a hole in the box. The hole can be made either using the plier or the screwdriver.
  • The next step is to expose the copper of the wire. But before exposing the copper wire, measure 2-2.5 inches (5-6.5cm) from the end and then strip the cord. A Paper cutter, knife, or plier would be good for the job, though some prefer a paper cutter or a knife since it is easier to peel off the insulation with them. Using a plier increases the chances of accidentally cutting through the copper wire.
  • In case your extension cord has multiple wires, you will need to get rid of the unnecessary ones. This is because only the hot(live), neutral and ground (earth) wires would be needed for the extension cord. Again, you can use either of the suitable options – a scissor or a plier.
  • Using the strain relief box connector or CGB, plug the hole made in step 1. Firmly lock it in place using a plier. Afterward, insert the wire and ensure that the CGB or the strain relief box is locked in.
  • After locking in the wire, the next step is to make grounds. A total of 2 grounds are needed, one for the outlet and another for the generator. Cut those wires.
  • Attach those ground wires and tighten them. You can utilize your fingers, plier, or stripper for this task.
  • Next, connect the remaining wires to the receptacle. After connecting, tighten them using a screwdriver. You can use the electrical tape in case you want it to be extra safe.
  • Place the receptacles on the cover of the square box. Before doing so, remove the screws and ensure that the receptacles have locked in place. Re-attach the removed screws so that the receptacles are held firmly in their place.
  • Now that one end of the wire has been taken care of, the next thing to do is to take care of the other end.
  • Strip a small piece off the other end to connect it to the male plug. Remove the screws of the male plug so that it is ready to take in the wire. Insert the wire and tighten the screws.

Necessary Precautions

At times, you would be tempted to use your extension cord without an absolute need, after all, you have made it with your own hands. However, it should be kept in mind that an extension cord is only a temporary solution. Consider connecting it fully if you intend to use it permanently with your generator. Furthermore, inspecting it from time to time would be a good idea since doing so would help in rectifying any faults.

Detach the wire if you detect a burning smell or if the wire is getting hot. This usually occurs when there’s a loose connection between the contacts. Sometimes, there may be a short in the wire. In such a case, you will need to replace the wire. Cutting off the defective area and replacing it with a joint may seem like a cost-effective solution but it can result in further complications.

Using an extension cord reel sounds like a practical solution for an extension cord but it is advised to stay away from it. Winding the extension cord around it can lead to a coil effect. Therefore, always make sure that the cord is free and isn’t interfering. Lastly, you can use your 30-amp cord for a lesser capacity generator but vice versa for this scenario isn’t possible.


It is doable, but it is generally not advised. This is because the use of the extension cord itself is something that should be temporary. Connecting multiple cords raises the likelihood of failure.

A 30-amp generator extension cord’s length should be anywhere below 100 feet.

+ posts

Ever since I was a kid, I've been fascinated by travel. I inherited this passion from my parents. Since my college years and to this day, I have had a passion for traveling in a motorhome. I am here to share my experiences with you.

We will be happy to hear your thoughts

Leave a reply

RV Camp Gear
Enable registration in settings - general