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IMPORTANT NOTES FOR EARTHING

1) Whether specifcally show i the !rawi" or ot# All e$%ip&et a! str%ct%res

shall i "eeral' (e "ro%!e! at two poits at opposite corers# All earthi"

!etails shall (e as per e$%ip&et earthi" !etails !r" #o t( *+,+-./.11#0) Gro%!i" co!%ctors i o%t!oor areas shall (e (%rie! ..&& (elow fishe!

"ro%! le2el#+) Whee2er a "ro%!i" co!%ctor crosses roa!s' ca(le trechers' %!er"ro%!

ser2ice !%cts# Pipe lies etc# shall (e lai! at least +..&& (ellow the&' (%t ot

less tha ..&& (ellow FG3 or shall (e re rero%te! ro%! the e$%ip&et

4str%ct%re 5o%!atio #*) Gro%!i" co!%ctor aro%! the (%il!i" shall (e (%rie! i "ro%! at a &ii&%&

!istace o5 1-..&& 5ro& the o%ter (o%!ary o5 the (%il!i" #a! "ates shall (e

coecte! to earth &at (y oe type#-) 6oectio with e$%ip&et with earthi" pa! shall (e (olte! type# coectio

(etwee e$%ip&et "ro%!i" lea!s 7MS 8at) a! &ai "ro%! co!%ctors 7*. !ia

MS ro!) shall (e wel!e! type #5or r%st pro!%ctio ' the wel!s shall (e clea with

wire (r%sh' treate! with re! lea! a! a5terwar!s coate! with two layers (it%&e

co&po%! to pre2et corrosio #,) All "ro%! coectio shall (e &a!e (y electric arc wel!i" #all wel!e! 9oits shall

(e allowe! to cool !ow "ra!%ally to at&ospheric te&perat%re (e5ore p%t ay

loa! o it# Artifcial cooli" shall ot (e allowe!#:) All are wel!i" o5 lar"e !ia&eters co!%ctors shall (e !oe (y or&al low

hy!ro"e cotet electro!es#) Ma;i&%& spaci" o5 hori

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1:) Earthi" ter&ial o5 each li"hti" arrester > capacitor 2olta"e tras5or&er

shall (e !irectly coecte! to ro! earth electro!e which i t%r ' shall (e

coecte! to statio earthi" "ri!#1) A%;iliary earthi" &at co&prisi" o5 *.&& !ia ro!s closely space! 7+..&&

; +..&&) co!%ctors shall (e pro2i!e! at !epth o5 +..&& 5ro& "ro%! le2el

(elow the operati" ha!les o5 the MOM (o; o5 the isolators MOM (o;es shall

(e !irectly coecte! to (e a%;iliary earthi" &at#1/) The earth electro!e to (e 5a(ricate! 5or - &ts le"th witho%t 9oits with

pro2isio 5or iter coecti" at least two %&(ers earth 8ats 5ro& &ai earth

&at4str%ct%re etc# the electro!e to (e erecte! (y ri""i" 1*.41-. && !ia # (ore%si" power ri" a! to (e flle! with &i;er o5 a* "ra!e ?etoite power 'slat a!

a2aila(le site soil #20) ?e!i" o5 earthi" ro! shall (e !oe pre5era(ly (y "as heati"#