what type of earthing system is this?

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dan.

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on a job at the mo, over head power cables with a separate earth so 3 cables in total.is this a tns system or tt??

 

sirsparkabit

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on a job at the mo, over head power cables with a separate earth so 3 cables in total.is this a tns system or tt??
More info dan please explain in detail what you have?

 

dan.

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righto old converted farm house in ormskirk. over head power cables with 3 cables.3 uninsulated cables come down to the house are then insulated then go down the side wall and into the property.2 cables go into a normal type fuse the other which is the earth goes to an earth conection bar.

 

sirsparkabit

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righto old converted farm house in ormskirk. over head power cables with 3 cables.3 uninsulated cables come down to the house are then insulated then go down the side wall and into the property.2 cables go into a normal type fuse the other which is the earth goes to an earth conection bar.
sorry mate i will leave this to the more suited who will be along soon no doubt:D

 

dan.

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im pretty sure its a tns system but would like some comformation. just in case.

 

paulh

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Like the Phone dno, If an earth is provided then it has to be a tn system doesn't it?

 

Admin1

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Could it be an old TT that has been PME'd? :|

 

Admin1

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Normally they are TN-C-S, Admittedly. But it is not uknown for a TT to be too.

 

steptoe

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more than likely TNS,

is it possible for you to trace the cable back to the transformer?

failing that, a loop test and PFC across all cables in turn will show up the likelihood of the different probabilities.

deffo NOT TNCS admin, the N E are NOT combined according to OP.

could be old TT where the pole is actually electrode,

wondering what type of trip is fitted now? is it an old voltage type????

could be an old TT without the earth, simply the incoming reference point for the trip.....

deffo needs a Ze ASAP methinks,,,

 

steptoe

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Normally they are TN-C-S, Admittedly. But it is not uknown for a TT to be too.
admin, you on the lemonade????? ; \

Terra Neutral Combined Seperate = IS = PME

Terra Terra = is simply what it says on the tin,

it canNOT be MULTIPLE EARTHed,

unless you count hammering more than 1 rod in, or you gonna put them in every 10metres back to the transfomer???? ?:| ? :|

 

Admin1

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Yeah I know ** In Matt Lucas voice ** Can I export PME?

 

dan.

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ze is coming in at 0.45 pfc is 550 so it looks like tns it is. Couldnt get in touch with dno.

 

steptoe

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ze is coming in at 0.45 pfc is 550 so it looks like tns it is. Couldnt get in touch with dno.
550kA ? or 0.550kA ?

what is that across? L N or L E ?

also can you do a loop test across L N too, give the ohm rating to centre point this way too, then can compare the PFC LN & LE and relate it to the centre point differential in ohms between Ln & LE.

thanks, sorry if it sounds a bit long winded but it does make a difference as to where your readings relate to at the transformer, ie, centre point or seperate Earth away from centre point.

(before you all start, I know centre point is Earth but in the interests of simplicity its easier to explain earth on TNS as being away(seperate) from centre point)

 

dan.

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550amps not ka ,crikey that would blowthe house to bits.across L-N

 
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righto old converted farm house in ormskirk. over head power cables with 3 cables.3 uninsulated cables come down to the house are then insulated then go down the side wall and into the property.2 cables go into a normal type fuse the other which is the earth goes to an earth conection bar.
I would not think it is tns on overhead as earth comes off armour on tns. Maybe originnally it had two phases and one of the phases has been changed to earth. A few pics would help.

Batty

 

dan.

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ive got 1 pic of where the cables attach to the house but have nowhere to host it to get it on here.

 
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