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my surge protection 'cpd', such as it is...

psychicwarrior
Good morning all


I have obtained the following [I feel as the] 'best we can do for now' information from the DNO. They were helpful in my test case request for info.


"...address 1:

LV underground - 362m

HV underground to primary-  2000m

No Surge protection devices


address 2:

LV underground to substation - 110 m

HV UG from substation to HV pole is 823m then 301m 11kV overhead then 190m HV UG to the primary substation.

Distance to cable termination with surge protection device from secondary substation is 1124m (823m 11kV UG + 301m 11kV Overhead).  The nearest cable

termination does not have surge protection installed. ..."


In relation to the risk assessment equation variables dealing with distribution cable lengths  ie. the Lpal Lpcl Lpah Lpch, how would one fit the given values into the variables ?


For addr1, ignore the HV (e.g. use zero for Lpah Lpch),  then take Lpcl as 362 and Lpal as 638 ?


For addr2, i'm not sure on this one ?


Thanks for your input.

Habs


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  • 0

    AJJewsbury:




    My home, like millions of others in the UK, has an underground electricity supply and an overhead telephone line from a pole in the street supplied by underground cables, so do I need a telephone line SPD more than a electric supply SPD?



    Or the bit of metal stuck up usually just above the highest point of the building, connected directly to some of the most delicate and expensive electronics inside? (the TV aerial)

      - Andy.

     




    My aerial is inside the loft, so is that better or worse?


    Andy B

Reply
  • 0

    AJJewsbury:




    My home, like millions of others in the UK, has an underground electricity supply and an overhead telephone line from a pole in the street supplied by underground cables, so do I need a telephone line SPD more than a electric supply SPD?



    Or the bit of metal stuck up usually just above the highest point of the building, connected directly to some of the most delicate and expensive electronics inside? (the TV aerial)

      - Andy.

     




    My aerial is inside the loft, so is that better or worse?


    Andy B

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