My home has an L14-30 type generator hookup that is located in an attached garage. About 50 feet away I have a barn with an LPG quick connect. In the event of a power outage my plan is to hook up a tri-fuel generator to the LPG connection at the barn and then run the generator cable over to the plug in the garage. Most L14-30 generators cables seem to be closer to 25ft in length so I'm wondering if there is some maximum limit to these cables from a safety or code perspective.

Would something like this cable be a safe option? I'm hesitant to buy it because its length seems to be an outlier.

Amazon https://a.co/d/3REQFag


3 Answers 3


With wires/cables code sets the minimum size gauge that can be used at certain amperage.

For 30 amps the minimum is 10 gauge. There is nothing wrong about using larger gauges.

There is no maximum distance, except the cost. The greater(much greater) the distance, the larger the gauge is needed, which can greatly increase cost.

10 gauge should be good for at least 75 feet. You start to go much beyond 100 feet is when to start looking at larges gauges.

The cables should have proper allowed markings/labels by the testing labs approved by your local government.


Amazon is an inherently dangerous place to buy electrical gear, since Amazon has opened its site to 3rd party sellers - such as the item you linked there. Amazon is not the seller and does not vouch for the quality. That means it is the same "quality" as buying on eBay, and the vast majority is cheap Chinese. These shoddy sellers use Amazon Fulfillment, which means it ships with Prime.

That said, there is nothing inherently wrong with long extension cords. On 240V circuits we don't worry about voltage drop until close to 200'. NEC does not mandate any particular voltage drop limit, though above about 10% you'll violate the codes requiring wires be low resistance enough to assure an instant breaker trip on a dead short.

Make sure your hookup is a proper inlet (thing in the wall has pointy prongs) and it is feeding into a generator interlock or transfer switch. If any combination of switch throws can cause utility power to appear at the inlet (very bad obviously), that also means generator power can find its way onto the utility lines and kill linemen. It can also interfere with your ability to stand the house up during an outage, since you're trying to light up the whole neighborhood.


Welcome, hopefully we can answer your question. The length would be ok, just be sure the gauge is large enough for your load.

The difference between ETL Listed and UL Listed is the testing lab. Both laboratories are good and well known and nationally recognized. ETL (formerly Edison Testing means a product was tested and approved by Intertek Testing Services. UL (Underwriters Laboratories) means a product was tested and approved by Underwriters Laboratories Services. (Laboratories). Either label indicates it was tested and approved by a Nationally Recognized Testing Laboratory.

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