Hi,

I would love some help understanding an issue I’m having on a 16mm SWA cable running from the CU in my house to the CU in the shed.

I believe there is a problem with the cable (possibly between E and N), and I have used a multi-meter to do some checks on the CU (shed side) and below you will see my finding.

Please note that the tests are done whilst the MCB in the house is OFF so there is no voltage at the shed whilst performing these tests, however the cables are still connected at the CU in the house (shed ones are disconnected).

https://1drv.ms/i/s!AicNdL7JWhGahawkCq1gV5yjwZM3uA?e=UoM1WT

https://1drv.ms/i/s!AicNdL7JWhGahawj2CAfR9zxn-Pi5g?e=Obqlme

I think my electric supply coming into my house is TN-S. I will attach a 2 photos above so someone might be able to confirm this.

Also to note i did a continuity test between the earth bar and the neutral bar in my CU in the house and we have a LOUD BEEP.

https://1drv.ms/i/s!AicNdL7JWhGahawcNYe4hV-GacO3cA?e=2mzlCy

Above is common (black cable from multi-meter) connected to N and red cable connected to E.

Multi-meter is in AUTO MODE set to OHMS and we get 2.1 ohms.

https://1drv.ms/i/s!AicNdL7JWhGahawWWt91uVD49sVKiA?e=w6s24B

Above is common (black cable from multi-meter) connected to N and red cable connected to E.

Multi-meter is in IN MANUAL MODE set to OHMS and we get 3.9 ohms.

https://1drv.ms/i/s!AicNdL7JWhGahawbWsXbg4qcmA6VaA?e=ZHEvAA

Above is common (black cable from multi-meter) connected to N and red cable connected to E.

Multi-meter is in CONTINUITY MODE and we get a LOUD BEEP with a reading of 7.9 (is this ohms?) – I do not know what this means.

But I do understand that there is a pathway between N and E which seems like that maybe the fault.

https://1drv.ms/i/s!AicNdL7JWhGahawU1iw4AK0u4_8v0w?e=Tt1fWV

Above is common (black cable from multi-meter) connected to E and red cable connected to N (notice I switched the cables around to see if it makes a difference).

Multi-meter is in IN MANUAL MODE set to OHMS and we get 0.0 ohms

I find this strange, but I don’t know why. Haha.

https://1drv.ms/i/s!AicNdL7JWhGahawS2aPPBwa4Fi_ynA?e=PRyDnv

Above is common (black cable from multi-meter) connected to E and red cable connected to N (notice I switched the cables around to see if it makes a difference).

Multi-meter is in CONTINUITY MODE and we get a LOUD BEEP AGAIN with a reading of 4.5 (is this ohms?) – AGAIN I do not know what this means. But I think something is wrong.

https://1drv.ms/i/s!AicNdL7JWhGahawZYfAcD4saxhHRFg?e=I0nULJ

Above is common (black cable from multi-meter) connected to N and red cable connected to L.

Multi-meter is in AUTO MODE set to OHMS and we get 5.063 M ohms.

I think this is MEGA ohms and I don’t understand if this is normal, I think this is normal.

https://1drv.ms/i/s!AicNdL7JWhGahawY10VSgWlnTrBv2A?e=YIOnj9

Above is common (black cable from multi-meter) connected to N and red cable connected to L.

Multi-meter is in IN MANUAL MODE set to OHMS and we get OPEN LINE.

I don’t understand why there is a difference between AUTO MODE showing over 5 MEGA ohms and this manual mode showing OPEN LINE, but I think this is GOOD and normal.

https://1drv.ms/i/s!AicNdL7JWhGahawaIPdmInzCpcFK1g?e=SGCVQc

Above is common (black cable from multi-meter) connected to N and red cable connected to L.

Multi-meter is in CONTINUITY MODE and we get a NO BEEP with a reading of OPEN LINE.

This looks OK to me.

https://1drv.ms/i/s!AicNdL7JWhGahawXMPHXIuM7a3eoDg?e=H2dJy1

Above is common (black cable from multi-meter) connected to E and red cable connected to L.

Multi-meter is in AUTO MODE set to OHMS and we get 5.99 M ohms.

Again I am not sure if this is normal.

https://1drv.ms/i/s!AicNdL7JWhGahawTQTuFMqUuID58Hg?e=D68YO2

Above is common (black cable from multi-meter) connected to E and red cable connected to L.

Multi-meter is in IN MANUAL MODE set to OHMS and we get OPEN LINE.

I think this is GOOD.

https://1drv.ms/i/s!AicNdL7JWhGahawVl-ZTh4bCmK7H8A?e=XHN1Mq

Above is common (black cable from multi-meter) connected to E and red cable connected to L.

Multi-meter is in CONTINUITY MODE and we get a NO BEEP with a reading of OPEN LINE.

This looks OK to me.

Does anyone have any thoughts as to what is going on?

Do you think I should do further tests or is it simple to say there is a NEUTRAL to EARTH fault on my 16mm2 SWA cable?

Help will be much appreciated.

Kind regards.

I would love some help understanding an issue I’m having on a 16mm SWA cable running from the CU in my house to the CU in the shed.

I believe there is a problem with the cable (possibly between E and N), and I have used a multi-meter to do some checks on the CU (shed side) and below you will see my finding.

Please note that the tests are done whilst the MCB in the house is OFF so there is no voltage at the shed whilst performing these tests, however the cables are still connected at the CU in the house (shed ones are disconnected).

https://1drv.ms/i/s!AicNdL7JWhGahawkCq1gV5yjwZM3uA?e=UoM1WT

https://1drv.ms/i/s!AicNdL7JWhGahawj2CAfR9zxn-Pi5g?e=Obqlme

I think my electric supply coming into my house is TN-S. I will attach a 2 photos above so someone might be able to confirm this.

Also to note i did a continuity test between the earth bar and the neutral bar in my CU in the house and we have a LOUD BEEP.

https://1drv.ms/i/s!AicNdL7JWhGahawcNYe4hV-GacO3cA?e=2mzlCy

Above is common (black cable from multi-meter) connected to N and red cable connected to E.

Multi-meter is in AUTO MODE set to OHMS and we get 2.1 ohms.

https://1drv.ms/i/s!AicNdL7JWhGahawWWt91uVD49sVKiA?e=w6s24B

Above is common (black cable from multi-meter) connected to N and red cable connected to E.

Multi-meter is in IN MANUAL MODE set to OHMS and we get 3.9 ohms.

https://1drv.ms/i/s!AicNdL7JWhGahawbWsXbg4qcmA6VaA?e=ZHEvAA

Above is common (black cable from multi-meter) connected to N and red cable connected to E.

Multi-meter is in CONTINUITY MODE and we get a LOUD BEEP with a reading of 7.9 (is this ohms?) – I do not know what this means.

But I do understand that there is a pathway between N and E which seems like that maybe the fault.

https://1drv.ms/i/s!AicNdL7JWhGahawU1iw4AK0u4_8v0w?e=Tt1fWV

Above is common (black cable from multi-meter) connected to E and red cable connected to N (notice I switched the cables around to see if it makes a difference).

Multi-meter is in IN MANUAL MODE set to OHMS and we get 0.0 ohms

__This occurs again even in AUTO MODE (no photo for this)__for ohms it gives a straight 0.00 instead of OPEN LINE.I find this strange, but I don’t know why. Haha.

https://1drv.ms/i/s!AicNdL7JWhGahawS2aPPBwa4Fi_ynA?e=PRyDnv

Above is common (black cable from multi-meter) connected to E and red cable connected to N (notice I switched the cables around to see if it makes a difference).

Multi-meter is in CONTINUITY MODE and we get a LOUD BEEP AGAIN with a reading of 4.5 (is this ohms?) – AGAIN I do not know what this means. But I think something is wrong.

https://1drv.ms/i/s!AicNdL7JWhGahawZYfAcD4saxhHRFg?e=I0nULJ

Above is common (black cable from multi-meter) connected to N and red cable connected to L.

Multi-meter is in AUTO MODE set to OHMS and we get 5.063 M ohms.

I think this is MEGA ohms and I don’t understand if this is normal, I think this is normal.

https://1drv.ms/i/s!AicNdL7JWhGahawY10VSgWlnTrBv2A?e=YIOnj9

Above is common (black cable from multi-meter) connected to N and red cable connected to L.

Multi-meter is in IN MANUAL MODE set to OHMS and we get OPEN LINE.

I don’t understand why there is a difference between AUTO MODE showing over 5 MEGA ohms and this manual mode showing OPEN LINE, but I think this is GOOD and normal.

https://1drv.ms/i/s!AicNdL7JWhGahawaIPdmInzCpcFK1g?e=SGCVQc

Above is common (black cable from multi-meter) connected to N and red cable connected to L.

Multi-meter is in CONTINUITY MODE and we get a NO BEEP with a reading of OPEN LINE.

This looks OK to me.

https://1drv.ms/i/s!AicNdL7JWhGahawXMPHXIuM7a3eoDg?e=H2dJy1

Above is common (black cable from multi-meter) connected to E and red cable connected to L.

Multi-meter is in AUTO MODE set to OHMS and we get 5.99 M ohms.

Again I am not sure if this is normal.

https://1drv.ms/i/s!AicNdL7JWhGahawTQTuFMqUuID58Hg?e=D68YO2

Above is common (black cable from multi-meter) connected to E and red cable connected to L.

Multi-meter is in IN MANUAL MODE set to OHMS and we get OPEN LINE.

I think this is GOOD.

https://1drv.ms/i/s!AicNdL7JWhGahawVl-ZTh4bCmK7H8A?e=XHN1Mq

Above is common (black cable from multi-meter) connected to E and red cable connected to L.

Multi-meter is in CONTINUITY MODE and we get a NO BEEP with a reading of OPEN LINE.

This looks OK to me.

Does anyone have any thoughts as to what is going on?

Do you think I should do further tests or is it simple to say there is a NEUTRAL to EARTH fault on my 16mm2 SWA cable?

Help will be much appreciated.

Kind regards.

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