MEN link in CU

[Nuitum]

Hello,

Please I want to know if it is ok or not

1. CU not MEN linked ( supply L,N connected to breaker directly, Ground connected direct to ground bus)

2. two wires connected to 1 neutral bus screw terminal due to not enough space

3. pigtail to neutral bus due to short wire length

4. Can I install cutout switch before consumer unit and your advise which type and brand so that I can isolate if work in CU for upgrades

5. ground wire was connected to concrete ( sockets were all 3 prongs)

 

this is for shop and my wife said inspection fail 2 times until pass  and connected ( so it passed PEA inspection with no MEN)

I was planning to rewire all

 

Thank you all

[Crossy]

Before you do any linking go for a walk and have a look at the supply poles. If you see a ground link from the neutral (usually the top wire) to a rod at the bottom of every 3rd pole or so then MEN is implemented by PEA and you can safely add a N-E link. If you don't see the rods, don't add MEN.

 

You should really install some form of earth leakage protection. Either a Safe-T-Cut device between the CU and the supply (if you do this the MEN link goes in the Safe-T-Cut box) or replace the incoming breaker with an RCBO.

 

Many of us use those Chang knife switches as main isolators, get a 100A one. We've had one member reporting an old one getting rather warm! Or, you could buy a UK style 100A main switch (cheap as chips from TLC in the UK) and put it in a little DIN box.

 

Is that earth actually a rod? Don't know? I'd put a new rod to be sure.

 

To be honest it doesn't look too bad, any reason you want to rip it all out?

 

[bankruatsteve]

1.  Are your neighbors MEN linked?  If not, then leave it as is; otherwise re-wire to MEN.

2.  That's OK.  Just make sure both cables nice and tight.

3.  Can't see that but should be OK.

4.  Sure.  I would go with Chang knife switch (DPST) rated for 100A and use 10mm² instead of fuses.

5.  So, that's just a hole in the concrete?  No good.  See requirements for ground in the pinned topics.  BUT - I don't see any ground wires in the CU (usually green).  It doesn't help to have 3-prong receptacle if there's no ground going to them.  Edit:  looking again it appears your grounds are white.  So, nevermind.  Another edit:  If there are two white going to receptacles, it could have been problematic making sure N to N and E to E.  Might be something to test.

 

Oops.  Didn't see Crossy's reply.  Well, I don't think we clashed anywhere.  ????

 

[Nuitum]

Crossy, bankruasteve,

 

thank you for the advise

Crossy attached is pic from pole outside the shop there is like a big wire protected with yellow pipe to the ground below the pole and next pole looks like transformer.

so is that what you mean that I can do a MEN link?

 

bankruasteve  the ground wire to rod is white with green tape Thai wiring style

yes as for grounding I think I will leave it as Crossy mentioned condition not so bad

but if it get damaged or worst condition I will change it ( as I think the PEA inspector is ok with it )

 

Thank you again now I have peace of mine. All my electrical knowledge is learned from this forum and done one project following Crossy advise and others and everything worked perfect

???? 

joke about the so called chang he installed power socket with light switch and I told him its wrong but as you know some Thai changs are stubborn and will not listen. So he finished I showed him that when I need the power socket then same time I have switch on the light switch but i say ok to him because I will check and do correct even sockets wire are not followed neutral and live have labels on the switch but its ok for AC but imagine if DC

[bankruatsteve]

Sounds like a plan.  Again, if they used white for both N and E to the power points, you really should test to make sure they got it right.  The plug in tester would be perfect for that.  Or, you could disconnect all ground at the CU, then use DMM on AC Volt setting and test each outlet between L and N - should be 220V (or whatever your service).  Test between L and E should be zero or maybe a few phantom volts.  If you get the reverse, then need to off power, switch the whites, test again.  Don't forget to reconnect grounds at the CU.  Cheers.  The reason this is important, is that 1) it is not correct to have N and E reversed and could be safety issue  2) it will cause Safe-T-Cut to fail if you ever put one in (and you should do that).

[xylophone]

3 hours ago, Crossy said:

Is that earth actually a rod? Don't know? I'd put a new rod to be sure.

Saw an earth wire coming down the power pole outside of my house and going into the concrete, so thought all was well and good, that is until I thought I would give it a bit of an inspection (after finding out a few other anomalies with the wiring in the house) and it turns out that the end of the "earth wire" was wrapped around a four-inch nail and somehow lightly embedded in the concrete with some dust/dirt around it.

 

Best to check as Crossy said.

[Metropolitian]

9 hours ago, Crossy said:

safely add a N-E link

But first don't remove the link, because...

9 hours ago, bankruatsteve said:

It doesn't help to have 3-prong receptacle if there's no ground going to them.  Edit:  looking again it appears your grounds are white.  So, nevermind.  Another edit:  If there are two white going to receptacles, it could have been problematic making sure N to N and E to E.  Might be something to test.

Right, but WAIT..

 

After looking to the box, what I see is that the wires to the receptacles are mixed at the two busbars. 

The white are supposed to be neutral but there are black wires too, and one blue in the earth bus bar.

There is the possibility that the black wire was neutral, white earth and red the live (old colors).

And somewhere in time the white used as neutral (only one has a green tape mark) and maybe black still used as neutral but looking at the wire gauge for lightning or used for earth at the receptacles.

 

Anyway, look in the receptacles first, and other points like the lightnings and as Steve said, test everything.

 

We wouldn't let happen the return path from the L to the N going to the earth bar, and the link was gone..