Replacing old wiring and putting in new system

[ghworker2010]

We had old electrical wiring removed on the 2 upper floors of our building. Last week an electrician installed new wiring on the floor below the top floor. Its all new and working well. Lights and all plugs working. But now we decide to use another electrician for the top floor next week bc the previous guy is so expensive. 

 

I can't see in his quote where he will connect the electric box from the top floor to the one below that's just been done. I purchased a new small 8 breaker switch box with RCD safety (for the top floor bc the existing one is so old) and he said he would take out the old one and install this new one for me. Obviously I think that all aircons and lights (wiring) will hook up to this new box on the top floor. Am I right in saying that this new box on the top floor will connect with the elec box on the floor below that has just been done? if this is the case I didn't ask him if he will be replacing that old wiring connecting the 2 boxes on the respective floors. Should I be asking for this? It seems a bit daft to be putting in all new wiring and lights and then not replace the wiring connecting the actual elec boxes? Is this correct?

 

Im a bit confused about how it all works as you can see but I assume all boxes are connected together from the top level box down to the one on the ground floor and then to the earth grounding rod outside. Is this correct? Thus for example if there is a critical incident on the top floor then breaker system should activate and the earth grounding rod outside should be effective? Is this how it works?

thanks

[bankruatsteve]

Unless exposed to water, sun, critters, etc. "old" wire does not necessarily need to be replaced.  A check for damaged insulation or corrosion is usually good to determine for that.  Not likely he would have the expensive equipment needed otherwise.  If you don't trust the new guy, maybe you should have stayed with the expensive one.  (?)

[ifmu]

its time to get a knowledgeable electrician  or trust google and tv posts

[Crossy]

4 minutes ago, ifmu said:

its time to get a knowledgeable electrician  or trust google and tv posts

 

This would normally be excellent advice, but have you found a good domestic sparks in Thailand? 

 

There are excellent and licenced electricians here, but they are mostly earning pots on MegaProjects or O&G.

 

[bankruatsteve]

So, you have 3 floors, yah? Let's call them G, F1, and F2. Assume there is primary CU on G which feeds the upper floors. (?) What is the main breaker size on each floor? What is the cable size between G-CU and F1-CU. What is the cable size between F1-CU and F2-CU? 

[Crossy]

Did your original sparks have / leave any drawings?

 

Please post photos of all the boards with the lids off (care please).

 

Let's see if we can work out what you have.

 

[Metropolitian]

Would be nice for us TVF-Sparks if you can take pictures of the boxes and wires and place it in this thread.

Sure you will get the right answers.

[xtrnuno41]

Of course your topbox will be connected with your groundbox, thats where the main supply comes in and also your earth rod and connections. 

Replacing wires isnt really necessary, only if it looks bad or doesnt have the right diameter of wiring for use. Or if they really made a mess of the wiring.

From your groundfloor box to your upper floor box the wiring should be bigger in diameter, as you have airco's running on upper floor?! Power consumption can be big, also if you have even more appliances running. The wire, groundbox to upper box, should be at least 4 mm2.   

Power consumption (watts) on a socket or other connection determines the wiring diameter.

[Metropolitian]

33 minutes ago, Crossy said:

Please post photos of all the boards with the lids off (care please).

You beated me to it. If just my wifi did not cut... ????

[Metropolitian]

On 3/20/2020 at 11:56 AM, ghworker2010 said:

Am I right in saying that this new box on the top floor will connect with the elec box on the floor below that has just been done?

There are two ways to have this done. 

The first is with each CU on all floors going straight to the 'Mother CU' at the ground floor, where bigger 'main'breakers can switch each floor seperate.

The other method is every CU on each floor is daisy-chained, in this case the link between the ground floor and first floor (In Thai: floor 1 to floor2) carries bigger current then the floor on top of it.