Thread: Sparkologists - 240V generators and RCD protection

A generator on its own is a floating supply, not referenced to earth, so it has no potential to earth, meaning it cant kill you between its active supply and earth......active to neutral is still nasty, but an RCD does not protect you in household stuff from that either

If you earth it, or its earthed to its body, its then referenced and there is potential to earth

Just to add, the earthing system used, as opposed to a "floating" system, due to being such a large system, (the grid), multiple ground faults can become dangerous and hazardous for supply if there was no earthing system

soooo
In short is a safety switch a good idea?
Not earthed as per matt?

Ill read that links later

S

One of the electricians at work has a Honda 2 and he has wired in an RCD along with an hour meter permanently onto his machine. He uses it for extended camping on moreton island, the hour meter helps him service it every 100 hours. He clocks up the hours pretty quick.

Although there is an earth tab on the machine there is no need to earth, he doesn't.

He indicated the best reference doc out there is a NSW mining doc on generators. A power boad with RCD is fine

Is this the one ? ...

http://www.resources.nsw.gov.au/__da...sion-2__5_.pdf

And is this useful ?

http://safe-electrical.mdz.com.au/wp...ry-Paper42.pdf

Hi Folks and first off I want to make something very VERY clear, I am NOT an electrician and have no intentions of passing out info relating to 240vac matters.

This is how this new gear came about.

Some 15 or so years ago, a woman was giving her young twins a bath.

She lifted one of the twins from the bath and as she did, she bumped a hair dryer into the bath, electrocuting the other twin.

This horrific event spurred a engineer into developing a safety device that would make such an event a thing of the passed.

15 years later and the IFS is developed and is now patented world wide.

Now to the next problem.

I have nothing to do with domestic ( house ) wiring, I only work with generators and inverters.

Generators and inverters are FLOATING electrical systems and are covered under AS/NZS 3001:2008

These standards specifically cover Electrical installations in Transportable Structures and Vehicles.

NOTE these standards are separate to the normal standards and those used in the Mining Industry.

Now please don’t be offended but most electricians have no idea of how Floating systems have to be installed and by most, I mean the vast majority.

So if you need some 240vac work done on a camper trailer, caravan or a motor home, you may find it vary hard to locate an electrician who actually knows the correct ( read legal ) way to carry out such installations.

And this advice is based on some 20 years of working on motor home and caravans, and dealing with a large number of RV manufacturers.

This following data is for a rough explanation and SHOULD NOT be used as a reference in any way.

In a floating system, if an RCD is used, and installed correctly, you can only use one Class 1 device safely and legally.

In a floating system, if an RVD is fitted, you can use as many Class 1 devices as you can power and they will all be safely protected and be legal.

Hey tim, where do we find any recent info these RVD's..........

I'm happy with the advice I have received from my electrician at work when I wired up my trailer......I couldn't imagine there would be anything too tricky in a mobile install

Do you have example of incorrect installs in mobile equipment....would like to see how mine sits

Cheers

Originally Posted by weeds

Do you have example of incorrect installs in mobile equipment

Hi Kelvin and unfortunately there are plenty of BAD installations done all the time.

A few years back I had an electrician contact me with an electrical problem with his mate’s NEW caravan.

I explained to him I was not an electrician and could not give him any form of electrical advice.

The problem his mate had was that when he bought his NEW caravan home, he set it up in his back yard and, luckily for him, he put down a rubber mat at the door so not to dirty his new caravan.

He plugged his van into the mains and then as he went to climb into his van he got a tingling feeling as he touched the side of the caravan.

The manufacturer had wired the active to earth in revers.

Under the law, the electrician was obligated to notify the authorities and he did so.

About a month later, I got a call from the electrician and he told me the Brisbane caravan manufacturer had to recall 4 other new vans they had wired the same way.

As I posted above, being an electrician, even a VERY good one, does not mean they have ever worked with floating power supplies.

I supply some of the largest RV manufacturers and some years back I got into a real knock down argument ( imagine, me arguing with anyone ) with an electrical engineer, employed by one of the largest motor home manufacturers.

They thought they had done the right thing by employing an electrical engineer but this guy was a joke in the most dangerous way.

I use Hager products and over the years have found them to back their products with very helpful technical support.

On this occasion they were instrumental in putting this horses rear of an engineer in his place.

While the incident is not that important it simply demonstrates that even when large companies try to do it right, they can come unstuck, so the average joe in the street is going to have a hell of a job getting it right.

Now as I have stated, I try to keep out of 240vac threads but two devices have come onto the market that has allowed me to prepare a new kit to resolve a major problem confronting RVers.

The problem, which is getting worse, is how to run a 3 way fridge and charge house batteries at the same time.

I have never been a fan of DC/DC devices because of their high set up price for such a small potential gain ( if any ), and they do not address the 3 way fridge problem.

I was told about the proposed introduction of the RVD a year or so back and this device would make a safe use of two other devices in a set up that would address the 3 way fridge/house battery charging in one go but would also have other uses for the devices when not powering the fridge and charging batteries while on the move.

This is the only reason I have made it my business to study and test the RVDs in both inverters and generators.