How would you....

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DonkeyDong

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All,

Currently I have DB1 split load, feeding DB3 (which is 30mA split load) via a submain (DB3 is an external building) with exported PME - not ideal.

I need to insert a new DB (DB2) in between DB1 and DB3. I intented to not use exported PME and switch to TT on DB2.

So basically, DB1 non RCD side via submain to DB2. DB2 will need to have a 100mA RCD (due to TT). This will then feed via a breaker to DB3 (which has 30mA RCD fitted) - which means DB2 100mA will now need to be type S to provide discrimination.

Eventually there will be DB4 (fed from DB2).

Any comments relating to the above ?

D.

 

cheggers

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I would fit a 100ma time delay on db2 because if there is a fault bigger than 100ma on db3 db2 rcd could still go before db3 rcd.

 
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