Badly grounded power pedestals

[reed_cundiff]

A lot of power pedestals on Mexican RV parks are badly grounded which can lead to nasty electric shocks if chassis is touched. We put a grounding cable into frame attached to grounding rod. Did notice a slight shock even so but dry sand is not a good conductor. Poured sea water (we are on beach in Yucatan) around the rod and it works perfectly.

The shock was so bad at Playa Azul that we never plugged in for the following three weeks up West coast of Mexico. Solar and LFP bank was sufficient for electrical requirements to include fridge on AC (2.5 kW PSWI) during day with propane at night.

[MEXICOWANDERER]

A "smart" ground rod connects both to receptacle ground pins and a mechanical connection to the chassis. I bonded neutral (bootstrap) to ground as well.

Does it work?

Several decades ago I was assigned a little used spot near the showers in Boca de Iguanas.

Plugged in and the campground electrical went up in smoke.

Line and neutral had been reversed at the campground service entrance. And subsequently (corrected?) at individual receptacles.

Whoppeee. Service with absolutely no overcurrent protection.

No worries!

The grid wasn't that badly damaged. The twist and tape wire connections took the brunt of the short damage. But a lot of smoke rolled out from under the thin plywood covers on the ground.

[almcc]

Yes, sounds like hot and neutral wires reversed at the pedestal, that's how I got a tingle off the RV when standing on damp grass. A ground rod will probably not help. A cheap plug in circuit tester will tell if you have a hot and neutral reverse (and other mis-wiring issues).

[ScottG]

If were inclined to spend time down there I would build myself an in/out box with switches to correct these miswires.

[MEXICOWANDERER]

Around three quarters of the RV park duplex receptacles I have checked over the years had hot and neutral reversed and the ground screw sitting all by it's lonesome.

Some parks had a merry mix of correct and incorrectly wired duplex receptacles.

Come to Mexico with an onboard energy management system and prepare to boondock 70% of the time. This is especially true south of Mazatlan and south of Mexico City. Especially true means >90% out of range of EMS parameters. Many facilities in southern Mexico have low voltage trippage during the day and high voltage trippage during the night. That is if you connect to a receptacle that has been wired correctly.

Ain't Life Fun?

Isolating neutral to earth leakage can get complicated. But it is highly recommended to do so BEFORE leaving home. One experienced fellow had a two tier 40 amp switch in his cable stowage compartment that allowed him to reverse hot and neutral instantly.

And buckets of salt water are an excellent adjunct to any grounding system. Smear a light coat of SILICONE DIELECTRIC GREASE onto a copper plated steel rod before burying it to protect it from salt water corrosion.

Silicone dielectric grease can be smeared onto a battery post before slipping on the lug and it will still pass current to start the rig*. When I built the hotel I proofed each receptacle by a direct line to earth ground short. Popped the 30-amp breaker every time.

*Not a hypothesis. Fact. Repeated. Collected bet money from sneering unbelievers.

[GordonThree]

But lacking ground shouldn't make the RV chassis hot. Is the Op parked under high tension transmission lines, or near a high wattage AM transmitter?

[ScottG]

In the US, two ground rods separated by 10' are required for each pedestal. Probably for just those kind of poor soil conditions.

[Old-Biscuit]

GordonThree wrote:
Sounds like you have something else going on, like hot and neutral reversed.

What's your EMS say?

Does sound like issue is with RV electrical vs the various/different power pedestals in Mexico.

Could be in RV Power Cord, could be loose wiring in Main Power Panel and if you have bad element in water heater it can cause 'hit skin' condition

[GordonThree]

Sounds like you have something else going on, like hot and neutral reversed.

What's your EMS say?