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The correct way is to do a ground rod and neutral bond at the service drop panel at the main power board of the park. Check CFE regs about this. Any CFE office will even make copies for you, free.
The correct way is to do a ground rod and neutral bond at the service drop panel at the main power board of the park. Check CFE regs about this. Any CFE office will even make copies for you, free.
That is exactly what the code I posted above says.
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Because of a solid rock ridge I had to use a 2nd ground point in Flores de Las Penas. Then tie all seven sites to the 2nd point.
Because of a solid rock ridge I had to use a 2nd ground point in Flores de Las Penas. Then tie all seven sites to the 2nd point.
If you can run hot and neutral to the sites I do not understand why you could not also run ground from the main panel. Why would any second ground be necessary?
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Even so, the 1st site had .4 - .7 volt difference between L1-LO versus L1 to earth ground. Site 2 was closer to one volt difference.
Even so, the 1st site had .4 - .7 volt difference between L1-LO versus L1 to earth ground. Site 2 was closer to one volt difference.
I have never heard or seen this unless something else is wrong in the wiring. Going back to the main panel neutral and ground are the same electrical point therefore should have the same voltage reading. If you do not get the same reading there is probably something wrong in the circuit.
You can connect a ground rod to the pedestal as long as you only connect it to the ground terminal in the pedestal. If the ground and neutral are connected in the pedestal you will have problems. Never connect ground and neutral together at the pedestal – bootstrap.
We use the term pedestal loosely here since we often do not see actual pedestals in Mexico. Even in the US many parks do not have what might be called a real pedestal. In Mexico the true RV pedestal can rarely be found as they are not something used in Mexico.
http://www.briansue2.blogspot.com
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OK howzabout 95% of the power pedestals found between Guatemala, Belice and the EUA? Are the receptacles in your home grounded correctly? What do you do when overnighting in your rig when you know the receptacles are not grounded?
OK howzabout 95% of the power pedestals found between Guatemala, Belice and the EUA? Are the receptacles in your home grounded correctly? What do you do when overnighting in your rig when you know the receptacles are not grounded?
Not all parts of the world use a grounded system. Two wire appliances do not have a ground wire. But most RVs are wired with a ground system so they should only be connected to grounded outlets - which are not always available - which is why we carry a ground rod for temporary grounding. We do not run heavy appliances if we do not have a decent ground.
In the US the minimum requirement (last time I read the code book) is for an 8 foot long solid copper rod 5/8 inch in diameter. The rod must be pounded into the ground vertically - never horizontally. We used to use "chipping hammers" (mini jack hammers) to mechanically force the rod the full depth into the ground. It is next to impossible to pull one out.
The extra earth connection was done because an eight gauge feeder circuit traveled 125' from the service drop panel but only a 12 gauge earth wire was used. Too small an earth for such a long distance. The eight gauge was continued as a manifold feeder for the sites. I used special 10-amp breakers at each pole to limit current. CFE wanted eight hundred thousand pesos to bring tres hilos (3-phase) 1,100 volt service to the nearest power pole. Then I would have needed a four thousand dollar 100 amp WYE transformer and revamp my end of the system 100%. Then I could have offered 30-amp site service. But RV'ers grumbled at the 16 dollar per night fee as it was.
I wish life was dominated by "should be" absolutes. But it isn't. Especially not down here. What I did for site grounding was tested and maintained. When is the last time you saw a "code" USA earth grounding rod actively tested and verified at full circuit amperage?
On any THREE wire feed circuit electronics, open up the circuit to expose the board. Now look at circuit protection component connections. All the MOVs are connected line to earth ground. No earth ground zero circuit protection. None. Zero.
Because I was there to verify and maintain a shallow depth ground system I provided it with confidence. I assume anyone with the ability to follow simple guidelines and instructions to be capable of doing the same with their own rig.
I posted a picture diagram above that shows main and sub panel wiring. That probably did not make it clear enough so I will try to split out the diagram into two separate pictures below to show both the main panel and the sub panel. The idea here being that the “sub panel” will represent a pedestal in an RV park.
First picture is the complete diagram showing both the main and sub panels. I then split the left side of that picture which is the main panel – and the right side of the picture which is the sub panel.
MAIN AND SUB PANEL
![[image]](http://i.imgur.com/3hSesZO.png )
In the main panel you will see the different wires and the colors typically found in electrical panels. At the upper left the sort of half circular heavy black lines represent the transformer up on the incoming power pole – or the newer type found on the ground when all wiring is done underground.
From the transformer we see three colors – red – white – black. WHITE IS ALWAYS NEUTRAL. BLACK AND/OR RED ARE ALWAYS HOT. Unfortunately in Mexico we can find any colors going anywhere and even all wires being the same color.
MAIN PANEL DIAGRAM SPLIT
![[image]](http://i.imgur.com/62SjWLW.jpg )
To the side we see a green wire – this represents ground but in most panels these days ground will be a bare copper wire.
The black and red are shown going to the main breaker. The diagram is not the best as they use grey as for many things. There are two sets of lines below the main breaker. These lines are meant to be metal strips that are connected to the main breaker – red to the left – black to the right. Circuit breakers are mounted to these strips which connects power to the breakers.
The white wire is shown connecting to another vertical grey line with circular sort of dots which are meant to represent screws. This is called a buss. Another grey line crosses vertically to the right side of the panel – this represents and metal bar that connects to another buss that is also vertical with dots for screws.
The green wire on the left is the ground wire and is shown as being outside the panel and pointing down with sort of arrows – this represents ground and the arrows mean this goes to a grounding rod or some other approved method of grounding.
If you trace out both the white and the green lines you will see they are both connected to the vertical buss in the main panel. This is what we mean by the “same electrical point”. No matter how you call it these two are now electrically connected throughout the system. They are the same.
We can only assume the two yellow round balls at the bottom represent lightbulbs or any other appliance connected to the circuit. The grey rectangle with the white box is supposed to be a light switch or any on/off switch for whatever might be connect to these circuits. It is just a rough idea of what a simple basic circuit and panel might look like. This is not meant to be exact.
Now note the black and red wires coming from a breaker in the main panel and going over to the sub panel. These are connected to a breaker with a set of connected switches represented by the white sort of stubby letter I or sideways letter H – meaning these are two separate circuits but they switch from a mechanically connected breaker – they are not electrically connected. This circuits takes both legs of the incoming hot circuits to the sub panel.
We also see both a green and a white wire coming from the main panel buss to the sub panel.
Now look at the sub panel diagram I split out from the original diagram. Note the red and black go to a new main breaker in this sub panel. Note also that the white and green wires now go to totally separate buss strips and are not connected in any way.
SUB PANEL DIAGRAM SPLIT
![[image]](http://i.imgur.com/nRD140L.jpg )
If we wanted to take this to a higher level of safety we could pound another ground rod in next to our pedestal and connect that rod to the ground buss – BUT NOT TO THE NEUTRAL buss.
If everything is done correctly according to the electrical code and this very simple and basic wiring diagram then you should get the exact same voltage reading if you test from either hot (red or black) to either ground or neutral. If you test from black to red you should get somewhere around 240 volts instead of the 120 volts you would get if you test black or red to ground or neutral. It is possible that you will not see 120 volts – you could see 127 or 113 – or anywhere in between. If you test black to red you may not get 240 – but chances are you are not going to see a lot of 240 connections in Mexico. If you do you might see something like 254 since the standard voltage in Mexico is usually 127.
If you measure / test voltage on a circuit and you do not see the same voltage from hot to either ground or neutral then there is something wrong somewhere in your circuit. One possibility could be wires between the main panel and the sub panel – either the neutral or the ground wire could be the incorrect size wire and not capable of carrying the necessary current. Something is wrong somewhere because neutral and ground are the same electrical point in the main panel so should always show the same exact voltage.
![[image]](http://i.imgur.com/9H35GmA.jpg )
As you increase distance from your service panel you must also increase wire size. This very basic chart gives some idea of how it works.
In Mexico we see this more often than in the US because there aren't many electrical inspections being done in RV parks in Mexico. We have seen what are supposed to be 30 amp circuits running several hundred feet but going all the way with 10 gauge wire. It won't work. If you have undersize wire in any circuit where you have to go any kind of distance you are going to be losing. If you run 12 gauge part way and 8 gauge part way you still have a weak link where you have the 12 gauge. If you are not consistent in your wiring you will not get the same test voltage. Using 12 gauge part way and 8 gauge part way is probably why you did not get the same voltage when you tested.
We were in an RV park a couple years ago when a caravan of big rigs pulled in and they all fired up their air conditioners and everything else. The main panel literally exploded with flames shooting up the main power pole and heat so intense the glass bowl on the meter melted to a blob of molten glass. There were three circuits running to about 10 RV sites each. The main panel had a 70 amp breaker. The electricians came and put in new wires and panel etc. They installed a 200 amp breaker where the 70 amp breaker had been but did not change any other wiring in any way. The next time a caravan pulls in it will be wires that will burn up somewhere underground instead of the main panel.
![[image]](http://i.imgur.com/3Df2VVQ.jpg )
In a large RV park, earth ground eddy currents will inevitably enter the picture. This will cause a >.1 volt Delta T L1 to L0 and earth. There are so few instances of finding no difference, that I find it remarkable when I encounter one.
The one and only correct way to address this is to run an earth ground web throughout the park. Multiple ground rods*, and multiple connections bonding the web back to the service drop panel L0 / earth bonding junction.
*strategically located.
Sadly, this is all wishful thinking.
But all it a recreation learning experience. Take your meter along and verify (or refute) what I have written. The more kind folks who know about this, the better educated RVers will be if that information is shared.
Mexico is the land of
Just
Get
By
As far as electrical system and design integrity is concerned. The practice of twisting wire ends together with linesman pliers then wrapping black around the ends is troubling.
Mexican businesses love to use dual pole breakers which sounds like a good idea for 127 vac circuits. Protect both L1 and L0.
Then a breaker fails. a line voltage breaker. So the "electrcista" thinks "well it has the other breaker", right? He then spices in and out line voltage wires together. Leaving neutral protected. Line to earth ground has no protection. These points sound ridiculous and they are. But they have to be dealt with, like it or not.
I'll add a caveat...
If you come to Mexico with a factory Energy Management System but no voltage correction device
Prepare to boondock - everywhere. Even when plugged in.
Prepare by purchasing like a Hughes Autoformer or similar