Fireproof fluorescent tube ballast

[andynic07]

Whilst the water pipe method is still used as it is a legacy way of doing things the new standard AS 3000 does state that a dedicated earth electrode buried at a certain depth in the ground must be used. I have seen first hand the problems of an insufficient earth electrode, this electrode is there to limit the rise in potential by providing a path for current to flow in the event that there is damage to the any part of the neutral circuit and if there is a piece of corroded galvanised pipe in the ground this can provide a very high resistance, generally the primary fuse on a house will be between 30 amps and 80 amps so if the earth to electrode resistance is any more than 10 ohms the electrode will not blow the primary fuse. I do not have access to an actual AS 3000 at the moment but here is an extract that refers to the AS 3000 which I believe is right "The majority of the electrical distribution systems in Australia require a connection between thesupply neutral and the customer’s earth system at each property, known as the Multiple EarthNeutral (MEN). This provides a safety back up to protect the electrical installation should acustomers earthing system become defective. In NSW, MEN bonding became the preferentialsystem in the 1960’s based on the metallic water reticulation system.
Prior to July 1976 most properties depended on their metallic water service pipes as part of theproperty’s electrical main earthing system. Properties built after 1976 are required to conform toAustralian Standards AS/NZS 3000 (Electrical Wiring Rules) and generally have a 1.2 mvertically buried earth rod that serves as the primary earth electrode. ". As for this statement "I understand that the current from the secondary coil in the step-down transformer can be effectively short-circuited by grounding it, thereby allowing work on power lines. The electricity does not return to coil, in which it was induced, not the earth" I am not 100% sure what you are referring to but I have the feeling that you may be confusing the permanent star point placed on the secondary side of a power transformer with what I call "line earths" which are a set of temporary wires short circuiting all three wires and bonds them to earth either through the LV neutral on a bonded earthing system or through a tested earth electrode on a separate earthing system which is put in place on a de-energised high voltage line to limit the rise in potential of that line and operate protection whilst it is being worked on in the event that the line is inadvertently energised. I think that you may be right in the fact that we are both getting caught up in industry lingo which may be confusing the intent of our statements, I know that I am guilty of this because it has been a long time since I have completed my apprenticeship so the main literature that I read now is Energex specific.

Thanks
Andrew

 

[Bluetongue1]

Standards introduced in 2007 do not invalidate my original comment, which applies to houses of all ages. However, it is useful to know about current trends and this can be incorporated in any future explanation of earth wiring and function. Hopefully I have addressed any shortcomings in the original with the following re-write...
“Houses used to use just their metal water pipes, where they go into the ground. This is no longer considered acceptable and nowadays a metal rod, such as a star picket, driven a metre plus into the ground, is utilised. Where there are copper water pipes, they will likely be wired up to the metal rod to give even more contact with the earth.”

No I am not confusing the star point with the “temporary earths”. I deliberately used the term “grounded” instead of “earthed” to see what response it elicited. It has a specific meaning as applied to electricity and varies slightly to the word “earthed”.

My apologies. The following sentence was incorrect: “The electricity does not return to coil, in which it was induced, not the earth.” It such have read: “The electricity does not return to the coil, in which it was induced and therefore its origin, but into the earth.”

Blue

 

[Snowman]

The only reason this is still going is to help educate people of the potential dangers of Electrical wiring gone wrong. No where does it state that the OP should be doing it himself and the OP has said that a qualified electrician will be doing the wiring so we can only hope they stick to that statement.
Snowman and AndyNic are qualified. So their statements stay.

@ Spongebob.
Your public comments against the moderation of the thread is in itself an infractable offence, but because you're trying to protect others I will not infract but just delete the post. Any objections should be submitted via a ticket to the support centre

technically he isn't wiring it anyway. It's a pre wired light fitting. It just doesn't conform to Australian standards.

 

[andynic07]

Blue

Blue, you seem to have quite a broard knowledge base from the conversations with you and other posts of yours that I have read. Can I ask what formal learning you have completed and what you do or did as your occupation throughout time?