Home Made 30A Shore Power Cable

[airdvr1227]

OK...wiring question. I have an L6-30 male end. I cut the end off of an extension cord.

Green is obviously the ground. I have black and white left. The plug wire inlets are labeled x and y. All three of the screws are brass. The ground screw has green dye. The instructions that came with the plug aren't very clear. Do I need to worry about polarity?
I'm not good with electric and I'd rather not just connect the wires, plug it in, and watch what happens

 

[Silvertip]

Re: Home Made 30A Shore Power Cable

You don't need to worry about polarity ONLY if you want to electrocute someone. But the plug you have is typically used for voltages above 120 VAC. So are you creating a 220 volt cord or a 120. Makes a big difference. If you are trying to connect to a 120 circuit then you need to identify the HOT and NEUTRAL in the receptacle you intend to plug into and wire the plug so that end matches the receptacle. You also need to ensure that when you are done, the other end of the cord is correct.

 

[airdvr1227]

Re: Home Made 30A Shore Power Cable

My goal is to be able to leave a trickle charger on the battery when I'm not there. It's 110v.

 

[Silvertip]

Re: Home Made 30A Shore Power Cable

Then you need to verify which is HOt and which is NEUTRAL in the receptacle you intend to plug into. In the cord, black is hot and white is neutral but you cannot ASSUME where hot and neutral is on the receptacle.

 

[airdvr1227]

Re: Home Made 30A Shore Power Cable

Thanks

 

[jlinder]

Re: Home Made 30A Shore Power Cable

Just curious. A 30A male connector and you are wiring it up to an extension cord. What size wire and what is the breaker rated for? While it sounds like you only want to run a charger with a small current draw you should make sure your breaker will trip before the wire will melt and catch fire.

 

[Fireman431]

Re: Home Made 30A Shore Power Cable

According to my brother (a master electrician), if you have the 30 amp plug shown here (L5-30), this is the wiring setup...



1) The large angled plug is your ground as well as your locking device on the 30 amp cord. This goes to the ground prong on the new female plug.

2) The larger of the 2 remaining blades is the white wire (neutral). This would be to the larger of the two female receptacles slots in your new plug.

3) The smaller remaining slot is the black wire.

He also advised that this is the normal setup regarding "per code" wiring, but your shore power may have reverse polarity.

Since you aren't plugging this into your actual on-board boat electrical system/ wiring, and using only a trickle charger or other small device, even if it is reversed polarity, you really aren't going to hurt anything. It's not optimal, but it will still work.

 

[airdvr1227]

Re: Home Made 30A Shore Power Cable

12 gauge grounded extension cord. Heaviest extension cord I've ever owned.

 

[airdvr1227]

Re: Home Made 30A Shore Power Cable

Actually, I found a similar picture and came to the same conclusion. Now all that's left is to plug it in an see what happens. I'm taking a sacrificial device (old blow dryer) just to make certain. Thanks for everyone's ideas. If the power dims for a second near the erie islands you'll know I was wrong...lol.

 

[Silvertip]

Re: Home Made 30A Shore Power Cable

Here's a little tip that may just save your life. Ever wonder why the third prong was added to the standard power cord?? To take care of the potential reversed polarity and to serve as a CHASSIS ground for certain devices. In the days of two wire plugs, so called electricians knew that devices would work regardless which way AC power got to it. What they didn't plan on was the fact that many power tools, radios, and other appliances had neutral (what they called ground) tied to the chassis. Now picture this carefully -- the outlet has reversed polarity. You have an electric drill with neutral tied to the chassis, or an internal wiring issue where neutral touches the metal chassis. Guess what happens when you touch that metal chassis and then touch a metal water pipe or other earth grounded object. You got it -- electric shock. If you aren't old enough to know how stuff was wired, and by whom, and you really think it's safe to just plug something in and it works makes it safe, then you are risking your life. MAKE SURE YOU KNOW WHAT YOU ARE PLUGGING INTO. A hair dryer is not a test device. A voltmeter is. Use it. Most two wire appliances these days have the neutral blade of the plug wider than the other so the plug cannot be inserted into the wall outlet incorrectly. Unfornately, if the plug and receptacle manufacturers had talked with each other years ago we would not need three wires. Reversed polarity would still be an issue but then a simple meter or test plug would be a quick check.

 

[jhebert]

Re: Home Made 30A Shore Power Cable

STOP---You are in danger of electrocution of yourself and a serious threat to others.

You have the wrong connector. A NMEA L6 connector is for 230-VAC circuits. It will not mate properly with 120-VAC twist-lock connectors. This is a good example of why you should not fiddle with electricity if you do not know anything about electricity, and why you should not rely on random advice from on-line sources. I am sure all the advice you have been given was well-intended, but it failed to identify the fundamental problem--and a dangerous problem. You need to get the correct connector.

Read more at http://en.wikipedia.org/wiki/NEMA_connector#NEMA_L6

The correct connector is an L5 series. Look for a 120-VAC, 30-A connector. This is the most common for marina power outlets.

 

[Fireman431]

Re: Home Made 30A Shore Power Cable

STOP---A NMEA L6 connector is for 230-VAC circuits. The correct connector is an L5 series. Look for a 120-VAC, 30-A connector. This is the most common for marina power outlets.

Correct. That is why I posted a pic for him...to make sure he is using the right male twist lock plug.