Shore power

From Nomad Life Wiki
An RV connected to shore power at a campground.

Shore power (or grid power, mains, or wall outlet power) refers to an electrical connection to the conventional AC power grid. This term is borrowed from marine use, referring to a docked boat connected to power.

Shore power is often used to recharge batteries, to run high-draw appliances like air conditioners or electric heaters, and when parked in campgrounds with utility service to avoid worry about battery charge levels.

Words of Wisdom: "...most people think that to have “RV” type shore power you need those special 30/50 amp plugs. I have a 115v plug. The male end of an extension cord (heavy gauge) that I have cable tied to the inside of my receiver hitch so it’s hidden." -- Captain_Dapper[1]

Note: this section is presently US-centric.

Shore power can run AC loads directly in campers so equipped, but more commonly it powers a converter/charger that runs the 12v system.

The most common places RVers use shore power is when plugged in at someone's house or at an RV park with full hookups (FHU).

(external image)

The most common types of campsite hookups are:

  • 15A/20A and 30A
  • 30A and 50A, with 50A costing more
  • 15A/20A only
  • 30A only

15A/20A shore power

Template:Http://www.diycontrols.com/images/15amp 20amp.JPG?150 15A power receptacles are the familiar ones found in a residence.[2] They can carry 1800W[3] and are the type of shore power many DIY RVs and vans are built around (assuming they have shore power receptacles at all).

20A power receptacles are rated for 2400W[4]. They look like 15A outlets but the "hot" leg has an additional spur.[5] This arrangement allows 15A plugs to go into 20A receptacles but prevents the heavier duty 20A plugs from being used in a less-powerful 15A circuit (which might overload the 15A circuit). Because of the backward-compatible 20A socket folks with 15A rigs can safely plug in at both 15A and 20A hookups.

Note: If "driveway surfing" on an extension cord, using a 10A circuit breaker on the RVs AC breaker box will prevent tripping a residential circuit breaker when the RVer might not have access to reset it. A 15A breaker might or might not, depending on whether the RV or residential breaker trips first.

A nomad can safely power a 15A RV from a 30A outlet with an adapter. 15A Extension cords should be 12-14ga for 50' cords and 10-12ga for 100' cords.

Mike Sokol of RV electrical fame, says:

> if there’s a 20-amp circuit breaker and 12-gauge wire feeding a 15-amp outlet, it’s actually rated for 20-amps of current. There’s an exception in the code as well as UL allowing this, so don’t worry. If you’re on a 20-amp breaker with 12-gauge wiring, then you have a 20-amp circuit, even if it’s using a NEMA 5-15 outlet.[6]

30A shore power

(external image) 30A is the standard setup for small-to-medium RVs.[7] It can supply 3600W,[8] typically sufficient to run an air conditioner and other items in the RV. The NEMA TT-30R plug is common. There is also a L5-30R twist-lock style.

If the 30A circuit on a 30A/50A pedestal is broken or malfunctioning the camper can use an adapter to get power from the 50A circuit.[9] Note this may incur a price increase from the park.

The RV can also run off a 15A/20A outlet with an adapter but would have to be careful about loads (heavy loads like a single A/C unit, electric cooktop, or microwave would have to be run one at a time).

50A shore power

(external image) 50A systems are most common in large, luxury RVs with two or more A/C units.[10] The 50A RV power pedestal has two 50A 120V legs[11] (split-phase) and can deliver 6,000W of power on each leg.[12]

50A to 30A adapters will use one leg of the outlet to feed the RV with 50A.

constant-duty rating

The constant-duty (continuous load) rating of each is 0.8 of the normal rating:

  • 50A is rated to 6,000w on each leg (4,800w constant duty)
  • 30A is rated to 3,600w (2,880w constant duty)
  • 20A is rated to 2,400w (1,920w constant duty)
  • 15A is rated to 1,800w (1,440w constant duty)

ports

[[https://m.media-amazon.com/images/I/81HoORya9rL._AC_UL436_.jpg?75 (external image)]] A shore power port is designed to let you plug power cables into the side of your van or RV. As discussed above, RVs typically use 30A/50A service -- they use this kind of port.

Vans typically use 15A ports. Some are pre-cabled so you can plug the inside cable to a power strip, breaker box, or other distribution device. A converter/charger can then be wired to the distribution point.

  • use a hole saw to bore the hole in the van wall to the port's specification
  • sand the edges to remove sharp edges
  • treat edges with paint, primer, rust preventive, etc to prevent rust. The edges will not be visible once the port is installed

power testers

Before plugging into shore power the RVer may want to test the receptacle for "good ground, open circuits, reversed polarity and safe voltage."[13] Note that the tester reports conditions at the time of testing; it might tell you if voltage is too high right now but not protect the RV if the voltage spikes later on.

surge protectors

Dogbone surge protectors are inexpensive, but they are generally only good for one surge (or maybe several small ones). More full-featured surge protectors will disconnect power to the RV in over/undervolt conditions and will reconnect after a certain period of stability.


Shore power gallery

See more in the Shore power category. For image credits, open image and click More Details.


Resources

Resource Description
Adding a shore power charger Learn how to add a shore power charger to an existing electrical systems
Search forums and groupsSearch van life discussion groups for "shore power"
Search related sitesSearch van life sites for "shore power"
Search other pages on this wiki for "shore power"

Some or all of the content on this page was originally sourced from this page on RVWiki