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Low ze High PFC help

goldenboy1818

Hi all I wondered if someone could please help

Doing some new builds with a substation about 30 yards from these two houses I'm currently on.

Initial testing I had a normal PFC, I don't know why but now the readings have changed (they have connected in a lot more houses on the site since ).

My ze is now around 0.03 and PFC around 8ka which is above my rcbo ka value of 6ka.

Not really come across this before, am I still ok where it has a 16ka 1361 protecting the house or is there something else I need to do ?

Thank you

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    What is the Zs at the DB? Even with fairly short tails, it must be lower than Ze. Then after the RCBOs, is there really a prospect of a dead short close to the CU?

    How are you measuring the Ze? What is the accuracy of your meter? I take the point, but when Ze gets so low (and PFC so high) you might need a specific low resistance ohmmeter rather than an MFT.

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  • 0

    What is the Zs at the DB? Even with fairly short tails, it must be lower than Ze. Then after the RCBOs, is there really a prospect of a dead short close to the CU?

    How are you measuring the Ze? What is the accuracy of your meter? I take the point, but when Ze gets so low (and PFC so high) you might need a specific low resistance ohmmeter rather than an MFT.

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