Shore Power cords

[micktu]

We have a small cabin cruiser with shore power. We wanted to move to the down stream side of the slip but there is no plug there. I will need about 20 additional feet of power cord to stay hooked up to the available plug. I'm finding that cords seem to run in 30' section. Is there a problem with running this much power cord. Also it would be two cords connected. Any problems with doing this?

[BeaverDave]

You state that you have a small cruiser so I will assume that you have a relatively lite load ( lights, battery charger etc.). I also assume that you are using a single 30 amp cord. Almost all of the manufactured cords that I have seen come in 25' and 50 ' lengths. When connecting 2 cords you should use the proper connecting hardware( securely connects cords and seals out moisture) . If you are connecting 2 50' cords (100' overall) you may get some voltage drop from the resistance in the cords.

Connect the cords, Turn on all AC loads, Use a meter at a wall socket to measure voltage. Should be at least 110V AC. Anything lower you may risk damaging some equipment from low voltage. Can you ask the marina to install another plug closer to the slip?

[TeamNutz]

I would check 2 things. Make sure that circuit breaker at the dock is 30 amp. I would also check with the wire manufacture that it can handle 30 amps continous at the length you have.

I watched two boats this winter catch fire because there wiring was not rated at 30 amp. The wire burned up before the breaker tripped. Remember the longer the wire the more amperage you need to make up the voltage.

Hope that helps, Ed.

[bobzeepgh]

"Remember the longer the wire the more amperage you need to make up the voltage."


The above statement is not true.

It should read, "the longer the wire, the larger the wire must be, in order to handle the voltage drop."

However, you usually won't have a voltage drop until about 100 feet or more. Consult the NEC for additional information.

[TeamNutz]

Correct
"the longer the wire, the larger the wire must be, in order to handle the voltage drop."

Same reason why if you use an air compressor plugged directly into an outlet it will be fine. If you operate the air compressor through extension cords the fuse/breaker will break due to to much amperage trying to feed through the line to reach the ultimate wattage needed to operate the device or air compressor. Simply electronic pie chart.

Regardless, if there is no issues with the boat at this point in the season I believe you will be ok as long as the wiring is not heating up.

This chart was pretty cool.
http://www.nooutage.com/vdrop.htm

[DiveBoat]

Real easy...What Gauge wire & total length? - Presuming 30 Amp Connectors?