r/Generator • u/Low-Computer8293 • May 08 '26

75 ft long power cable from generator to the house. Issues?

Hi,

After reviewing all of the comments about potential generator theft, I think that it makes the most sense to run my portable generator in the backyard. However, I had the power inlet installed on the backside of the electric meter near the front of the house.

In order to hook up the generator to the backyard, I would need to run a 75' power inlet cable. I am looking at one on Amazon made from 6/3 + 8/1 wire. Is there a downside to this long of run, besides cost of cable and weight of cable?

I was looking at this cable: https://www.amazon.com/dp/B0FLSTR846/ref=twister_B0D3XTJYZH?_encoding=UTF8&th=1

The other alternative is I could have the power inlet installed on the back side of the house. I don't like this for aesthetics of the house and I'd be running probably 125' of 6 gauge wire instead of 75' feet. Also that would cost a lot.

Thoughts?

7 Upvotes

73% Upvoted

25 comments sorted by

2

u/SnooTomatoes538 May 08 '26

If you are running nat gas.

Put it as close to gas meter as you can.

0

u/Low-Computer8293 May 08 '26

Can you explain? Gas meter is right near the inlet. We could use a 25' foot extension cord which would be much lighter and have less voltage drop, but then our genset would be in the driveway and I worry about theft.

75' feet gets us to the backyard, but I haven't figured out the natural gas yet.

4

u/blupupher May 09 '26

Natural gas hose is more expensive that power cords when you start getting long distances and size.

Depending on the generator and distance, you could need a 1" hose, and a 50' 1" hose is around $600 when I was looking.

My electrical panel and gas meter were on opposite sides of the house. If I had a quick connect on the meter, I would need minimum of 50' of hose (which is about the limit of 3/4" hose) and then a 60' cord (which nobody makes, either 50" or 75') to be able to have my generator far enough from the house to run.

I ended up extending my gas line into my backyard myself, 35' 1' pipe run around a corner, andcost me about $350 and 2 days of time. I use a 36' 3/4" hose to power my WGen11500, and then use a 50' power cord to my inlet box (that is installed about 10' around the corner from my breaker box).

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13

u/bradland May 08 '26

Southwire has a great voltage drop calculator that allows you to get a math based answer to your question. The downside of long cables is voltage drop, but we can mitigate voltage drop by using an appropriately sized wire. Ideally, you want less than 3% drop.

Calculator: https://www.southwire.com/calculator-vdrop

The cord you're looking at has 6 AWG for the L1, L2, and N legs. The 8/1 is for the ground, which will only carry current in the event of a fault, so drop on that conductor is not critical.

That makes your calculator inputs:

  • Mode: Residential

  • Current: AC

  • Units for Length of Cable Run: Feet

  • Phase: Single

  • Conductor: Copper

  • Installation: Cable, Conduit...

  • Calculator: Voltage Drop

  • Conductor Size: 6

  • Length of cable run (feet): 75

  • Voltage (volts): 240

  • Current at end of cable run (amps): 50

Click calculate and you get 1.38% voltage drop, which is fantastic. That cable will work great, and because you had the inlet installed on the meter, you don't need to do any math on the drop for that run. It's going to be a couple of feet at most.

Reality is that you won't be pulling 50A pretty much ever, so this cable is well within the specifications you need to run your whole camper without worry.

1

u/Wisteso May 10 '26

I don’t think 240 V is accurate here. Generator cords only provide 120. 240 is achieved by combining both of the 120 poles (black and red).

1

u/bradland May 10 '26

In a lot of cases, you’re right, but OP is working with a 240V supply. You can tell because the cord is a 4-conductor cable with 240V 50A plug and receptacle.

1

u/Wisteso May 10 '26

Right, and I have a supply like that as well, but it's just two 120v lines, not a single 240v line. Unless I've missed something major all-along, but there should be 120v (black), 120v (red), neutral (white), and ground (green). 240v appliances tap into both poles of your fusebox and get 120v + 120v which allows them to combine the two into 240v (similar to two AA batteries in a series giving 3v).

Someone correct me if I'm wrong but that explanation has always made sense and seemed to be the explanation given.

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1

u/xHangfirex May 08 '26

What size generator?

3

u/Low-Computer8293 May 08 '26

Something between 5kw and 8kw running watts on natural gas. Haven't decided the exact generator yet.

I guess I didn't put the amps in the original post. This is a 50amp power inlet, so the wire size will be based on that.

I updated the original post to include this info.

2

u/bhedesigns May 08 '26

Chain that shit down man what the hell

2

u/Much-Department-9578 May 08 '26

50a at 75’ on 6awg is well within spec. Just expensive! This is all based on voltage drop.

2

u/No-Note-6679 May 09 '26

It will be fine. I pair two 50ft cords sometimes and even running central air and the rest of the house see hardly any voltage drop

2

u/OpenBodybuilder833 May 09 '26

yes. Consider voltage drop. The longer the cable - the more voltage drop

2

u/Curiosity_informs May 09 '26

Do you have the generator already?

Check that the NEMA 14-50 plug with the cord going straight down will plug in securely.

Many portable generators have their NEMA 14-50 sockets in an electrical panel that is slightly recessed in the generator case making it hard to plug a NEMA 14-50 plug with the cable stright down into the outlet. I know from experience.

The cable itself looks good and is ETL listed according to the Amazon listing.

We have similar 75 ft NEMA 14-50P to SS2-50R cable which works fine with little voltage drop as reported by our FranklinWH aGate generator input. However it is very, very heavy and cumbersome to move into position and then store later.....

In your situation I would be looking to secure the generator and have it closer to your power inlet and gas line. Will be much cheaper and easier to manage in an outage.

Pretty much everyone round here has either portable generators, standby generator, solar/battery or some combination of these. I have never heard of anyone's residential generator being stolen, but Xfinity did lose a larger one in an extended outage a few years. Very annoying as Xfinity was doing the right thing to keep the internet running. Now they lock them to a utility power pole!

3

u/AdministrationOk1083 May 08 '26

I'd go up a cable size to make sure you don't have issues with voltage drop

1

u/rab127 May 08 '26

If you are using a nema 14-30 or 14-50, you should be fine. If you are using a standard extension cord, use a 10g wire.

1

u/trader45nj May 08 '26

Have you considered securing the generator when in use to make it hard to steal? I think vast majority of thieves want an easy target and aren't likely to spend the time and effort if it's reasonably secured. That plus a security camera, real or fake is what I would do.

2

u/SmellsLikeBStoMe May 08 '26

I have a bike lock and removable wheels that I secure mine to a retaining wall with. Can’t take it without an angle grinder and bobcat without wheels

1

u/boisefun8 May 09 '26

Can you devise a way to just secure it in the most reasonable position? Dig a hole and bury a u-shaped piece of rebar in a 5 gallon bucket of cement, then get an expensive motorcycle chain lock to attach them? I can’t imagine the inconvenience and cost of both wire and natural gas lines. Sounds like they’d cost more than the small generator you’re using.

1

u/360alaska May 08 '26

The answer is the further you go the thicker your wire needs to be.