1 
                                                                        
                                                                     g]=u'0f ३४४:२०५२  
                                                                                                                   NS: 344 : 2052  
                                                                                
                                                                                                                                                     दोस्रो ऩुनरयऺण : २०७४/१०/०९  
                                            
 
 
 
 
    
 
    g]kfn u'0f:t/                                                                                    
NEPAL STANDARD  
   
 
PVC insulated cable for fixed wiring with copper  
conductor  
 
 
 
 
 g]kfn ;/sf/                                                                                                                        
pBf]u dGqfno                                                                                
g]kfn u'0f:t/ tyf gfktf}n ljefu  
फाराजु , काठभाडौं  
 
 
 
            
          
 
                                                                                                                                                                                                                                                                                NS 344:2074  
2 
                       
 
 
                                                            NBSM  
sf7df08f}, g]kfn .  
g]kfn u'0f:t/ kl/ifb \ 
Nepal Council for Standardization (NCS)  
ने.गुण.३४४ -२०७४  
PVC insulated cable for fixed wiring with copper  
conductor  
दोस्रो ऩुनरयऺण  
अध्यऺ  
भानननम  सुननर फहादुय थाऩा, उधोग भन्त्री  
उपाध्यऺ 
  श्री माभ कुभायी खनिवडा , सनिव , उधोग भन्त्रारम  
सदस्यहरु 
l;=g+=       gfd                                             ऩद                             ;+:yf 
१.      श्री रयषषयाज कोईयारा        सह-सनिव              उधोग भन्त्रारम  
२.     .................. .......               सह -सनिव              वाणणज्म भन्त्रारम  
३.   श्री सुयेन्त्र ऩसाद सुवेदी           सह-सनिव              षवऻान िथा प्रषवनध भन्त्रारम  
४.   ..................................                     सह-सनिव              खाध प्रषवनध िथा गुणननमन्त्रण षव.  
५.   ..................................                    सह-सनिव              बौनिक ऩुवााधाय िथा मािामाि भन्त्रारम  
६.   श्री डडल्रीयाज नघनभये          सह-सनिव              कानुन िथा संसदीम व्मवस्था भन्त्रारम  
७.  श्री सुभनरार श्रेष्ठ                 सह -प्राध्माऩक            षरबुवन षवश्वषवधारम    
८.  श्री प्रा.डा. डदऩक प्रसाद सुवेदी         प्राध्माऩक            काठभांडौ षवश्वषवधारम      
९.  श्री ऻानेन्त्ररार प्रधान                                      नेऩार उधोग वाणणज्म भहासंघ         
१०. श्री डदऩक श्रेष्ठ                                                    नेऩार िेम्वय अप कभसा  
११. .....................                                  उऩबोक्ता सयोकायवारा संघ संस्था  
१२. श्री नसजाना फुरााकोटी                               उऩबोक्ता सयोकायवारा संघ संस्था  
१३.श्री अरुणदेव                                                            षवऻ  
 
 
 
सदस्म सनिव  
श्री षवश्ववाफु ऩुडासैनी , भहाननदेशक ,ने.गु.िथा ना.िौ.षव.  
 
 
                                                                                                                                                                                                                                                                                 NS 344:2074  
3 
  
 
 
 
 
 
                            प्राविधिक सधिधिको बैठकका पदाधिकारी हरु (२०७४/०९/१३)  
 
ने.गुण.३४४ -२०७४  
PVC insulated cable for fixed wiring with copper  
conductor  
 
                      श्री षवश्ववाफु ऩुडासैनी , भहाननदेशक , नेऩार गुणस्िय िथा नाऩिौर षवबाग  
                      श्री योभी भान्त्नधय , उऩ-भहाननदेशक , नेऩार गुणस्िय िथा नाऩिौर षवबाग  
                      श्री दीनानाथ नभश्र , उऩ-भहाननदेशक , नेऩार गुणस्िय िथा नाऩिौर षवबाग  
                      श्री प्रभोदा प्रधान ,उऩ-भहाननदेशक , नेऩार गुणस्िय िथा नाऩिौर षवबाग  
                      श्री भाधफ प्र. आिााम , नसडटजन नेऩार प्रा.नर.  
                      श्री गणेश प्र. ऩाठक , नेऩार गुणस्िय िथा नाऩिौर षवबाग  
                      श्री अननर शाक्म ,  नेऩार गुणस्िय िथा नाऩिौर षवबाग  
                      श्री डदऩेन्त्र कु. झा , नेऩार गुणस्िय िथा नाऩिौर षवबाग  
                      श्री िन्त्र दत्त कंडेर ,काठभांडौ षवधुनिम व्मावसामी संघ  
                      श्री नबभरार श्रेष्ठ ,नेऩार ईरेक्रीनसमन संघ ,बोटेवहार  
                      श्री प्रबाकय शभशेय याणा ,डहभ ईरेक्रननक्स  
                      श्री होभनाथ ऩोखयेर , नेऩार ईरेक्रीनसमन संघ ,बोटेवहार  
                      श्री आनशष नसग्देर ,नेऩार ईरेणक्रकर एण्ड ईरेक्रोननक्स म्मा. ए.  
                      श्री उऩेन्त्र फडार ,सोसाईडट अप ईरेणक्रकल्स ईणन्त्जननमास नेऩार  
                      श्री याजेन्त्र प्र. कुशवाहा , शहयी षवकास िथा बवन ननभााण षवबाग  
                      श्री नयहयी बण्डायी ई.ई. , , नेऩार गुणस्िय िथा नाऩिौर षवबाग  
                      श्री मुवयाज बण्डायी ई.ई. , , नेऩार गुणस्िय िथा नाऩिौर षवबाग  
                      श्री सुफोध खनार ,नेऩार ईरेणक्रकर एण्ड ईरेक्रोननक्स म्मा. ए.  
                                                                                                                                                                                                                                                                                 NS 344:2074  
4 
  
 
                                       g]kfn u'0f:t/  
)=k|:tfjgf  
 
!=   g]kfn u'0f:t/ -k|df0f lrGx_ P]g @)#& n] k|bt clwsf/ k|of]u u/L g]kfn u'0f:t/ kl/ifbaf6 u'0f:t/ lgwf{/0f ug{ 
o; ljefunfO{ ePsf] lgb]{zg / gLlt cg';f/ /fli6«o :t /df u'0f:t/ k|n]v हरु | tof/ kfg]{ l;nl;nfdf cfjZos 
tl/sf / 9frfdf of] u'0f:t/ k|n]v th'{df u/L k|:t't ul/Psf] 5 . o;n] g]kfn u'0f:t/ ;+u ;DalGwt ;a} kIfsf 
lgldt cfjZos lgb]{lzsfsf] sfo{ ug]{ 5 .  
 
@=  of] k|n]v tof/ kfbf{ u'0f:t/ lgwf{/0fsf k|n]v ;DaGwsf cGo b]zx?n] / cGt/fli6«o ;+u7gx? n] ckgfPsf k|0ffnL, 
rng, tl/sf / 9f ¤rfnfO{ oyf]lrt Wofgdf /flvPsf] 5 . o;n] th'{dfsf] nflu ljz]if u/L b]xfosf] ljb]zL tyf 
cGt/fli6«o ;+3 ;+:yfsf] k|n]v tyf cGo ;fwfgx? sf] ;xof]u lnOPsf] 5 .  
 -s_ cfO{=P;=cf]= — OG6/g]zgn cu {gfOh]zg km/ :6f088{8O{h]zg  
 -v_ lj=P;=cfO{= —  la|l6z :6 \of088{ O{lG:6Ro";g  
 -u_ lj=cfO{=P;= — Ao'/f] ckm O{lG8og :6f088{   
 
#= k|n]v tof/ kfbf{ vf; Wofgdf /flvPsf a'+bfx?  
 
 #=! u'0f:t/ k|n]vsf] th'{df ubf{ cGo k|n]vsf] s'g} klg kl/R5]bsf] pn+3g x'g ghfcf]; elg oyf;So  xf]l;of/L 
/flvPsf] 5 . c;fjwfgLaf6 s]xL pn+3g x'g uPsf] 1ft x'g cfPdf o;df rflxg] ;+zf]wgsf] nflu oyflzw| sbd 
p7fO{g] 5 .  
 
#=@   b]zsf] P]g lgod cGt/tu k/]sf] ;a} फुंदाहरु  |nfO{ oyf]lrt dfGotf lbO{ o;sf] s'g} b \kmf tyf kl/R5]bsf]  pn+w g 
gx'g] u/L of] u'0f:t/ k|n]v tof/ kfg]{ sf]lz; ul/Psf] 5 . sy+sbflrt u'0f:t/ k|n]vsf] s'g} efudf pNn]lvt 
s'/fहरु| xfn k|rngdf ePsf tyf eljiodf cfpg] P]g lgod ;+u aflemg uPdf To:tf -k|n]v_ sf s'/f हरु | :jtM 
lg:s[o x'g]5 .  
 
#=#   gfktf}n O{sfO tyf ltgLx|sf]  |kfGt/ ubf{ :6fG88{ gfktf}n P]g cGt/u{t h] hlt lgodx| 5g \ ;a}nfO{ oyf]lrt 
dfGotf lbO{ logLx|sf] k|of]u ul/Psf] 5   
 
#=$ o; k|n]vsf] th'{df g]=u'= tyf cfO{=P;=cfO{= / To:t} cGo cGt/fli6«o ;+3 ;+:yfx? sf ;DalGwt laifodf 
lgb]{lzsf k':tLsf tyf u'0f:t/ lgwf{/0 f / u'0f lgoGq0f ;DaGwL cGo   sfo{x?sf] k|ltj]bg O{Toflbaf6 ;fdflu|x? 
oyf;Dej k|fKt u/L ltgLx? sf] l;kml/; cg'?k  ;fdfGh:o Nofpg vf]lhPsf] 5 .  
 
#=%  o; k|n]vsf] th'{df ubf{ gfkgtf}n OToflb ljleGg O{sfO{x रुsf] nflu cGt/fli6«o If]qdf rln /x]sf] ax'dfGo O{sfO { 
tyf cfO{.o;.cf] n] ;d]t l;kml/; u/]sf] P;.cfO{ OsfO{ k|0ffnLnfO{ oyf;Dej k|of]udf NofPsf] 5 .  
 
 
 
 
                                                                                                                                                                                                                                                                                 NS 344:2074  
5 
  
%= o; u'0f:t/ k|n]v २०५२  ;fndf klxnf] rf]6L k|sfzg ePsf] lyof] . ;f] k|n]vdf ePsf lalGg रुडटहरु x6fpg / 
उत्ऩादकहरु / v/Lbstf{ हरु] cfjZostf हरु|nfO{ k"lt{ ug'{ o; klxnf] ;+zf]lwt k|n]vsf] cfjZostf x'g cfPsf] xf] . 
pTkfbsx?  / v/Lbstf{sf] ;'emfjx? lnO{ o; k|n]vnfO{ klxnf] ;+zf]wg ul/Psf] xf] .  
 
&= o; u'0f:t/ k|n]vdf PVC  insulated cable for fixed wiring with copper conductor ] laj/0f 
;DalGw k|fljlws kIfn fO{ dfq ;dfa]z ul/Psf] 5 . sf/f]af/ ;DalGw s'/fx?  o; k|n]vsf] If]q leq kb}{gg \ .  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
                         
 
 
 
 
 
 
 
 
                                                                                                                                                                                                                                                                                 NS 344:2074  
6 
  
                        PVC   INSULATED CABLE FOR FIXED WIRING WITH COPPER CONDUCTOR  
 
1 SCOPE  
This standard covers  the  requirements,  sampling  plan,  criteria  for conformity,  marking  and packing  for  
the  following  types  of  unarmored  PVC  insulated  cables  with  copper  conductor  for  electric  power  and  
lightning  for  voltage  up to and including 750V   to  be  used  for  fixed  wiring  purposes:  
a) Single  core(Unsheathed ) 
b) Single  core (Sheathed)  
c) Circular  twin,  three  and four  core (Sheathed)  
d) Flat  twin  with  or  without earth continuity conductor  (Sheathed)  
e) Flat  three  core(Sheathed)  
 
2. NORMATIVE REFERENCES  
The standards given below are necessary adjuncts to this standard . 
      NS  no.                                         Title  
      NS 340                          PVC vocabulary (cables, conductors, and accessories)                       
      NS 342                          Copper conductor for insulated cabl e 
      NS 285 Part (1 - 8)      Test method, PVC insulated cable  
      NS 1* ….              
      NS 2* ….            
      NS 3*……               
      NS 4* …..                
      NS 5* ….                        
 
3 TERMINOLOGY  
3.1 For the purpose of  this  standard,  definitions  given  in NS 340  shall apply  in  addition  to  the  following – 
3.2  Type  Test  -  Test carried  out  to  prove  conformity  with  the  specification,  these  are  intended  to  
prove  the  general  quality  and  design  of   a  given  type  of  cable.  
3.3  Acceptance Test  -  Test  carried  out  on  samples  taken  form  a lot  for  the  purpose  of  acceptance  of   
the  lot.  
3.4  Routine  Test  -  Test  carried  on  each  cable  to  check  the  requirements  which  are  li kely  to  vary  
during  production.  
3.5  Optional  Test  -  Special  tests  to  be  carried  out  when  required  by  agreement  between  the  purchaser  
and  supplier.  
3.6 Earth Continuity Conductor (ECC) –It is a part of earthing system which joints or b onds together all the 
metal parts of an installation. It is connected to earthing lead at connecting points.  
3.7 PVC Compound – Combination of materials suitably selected, proportioned and tested, of which the 
characteristic constituent is a plastomer poly vinyl chloride or one of its copolymers. The same term also 
designates compounds containing both polyvinyl chloride and certain of its polymers.                                                                                                                                                                                                                                                                                  NS 344:2074  
7 
 3.8 Cable Code: The following code shall be used for designating the cable:  
 
  Constituent  Code Letter  
 PVC in sulation  
 PVC sheath  
Suitable for outdoor use  
PVC with flame retardant (FR) 
properties  
PVC with flame retardant low 
smoke and halogen properties  Y 
Y 
OU 
FR 
 
FR-LSH  
                                  
Notes:  
1. No code letter is required when the conductor material is copper.  
2. In case of copper single core unsheathed PVC cable with FR or FR – LSH properties, the abbreviation FR or 
FR-LSH to be used after the complete cable code that is for example, Y (FR) or Y (FR -LSH).  
3. In case of copper multicore PVC i nsulated and sheathed cable with FR or FR -LSH properties, the 
abbreviation FR or FR -LSH to be used after the cable code, that is for example YY(FR) or YY(FR -LSH).  
                                                                      
4 PHYSICAL CONSTANT FOR  COPPER   
4.1  Physical   constant of  copper  conductor  shall  be  as  per  the  values  given  in  clause 3 of NS 342 -2052.  
 
5 REQUIREMENTS   
5.1 General requirements of copper conductor shall  be as per Table 1.  
5.2 Construction of conductor: The construction of cable shall be as given in Table 2 and Table 4.  
5.2.1 In case of stranded compacted circular and shaped conductors , the ratio of larger to smaller diameters of 
two wires before stranding in the same conductor shall not exceed 2.  
5.3  Dimens ions,  weight,  and  resistance  of  circular  copper  wire  shall  be  as  per  the  values  given  in  
table 1.  
5.4  Dimensions,  wire  number  and  resistance  of stranded conductor  shall  be  as  per  the  values  given  in  
table 2.  
5.5  During  annea ling  test  of  copper  conductor  minimum  percentage  elongation  shall  be  as  per  the  
values  given  in  table 3.  
5.6  Nominal  thickness  of  insulation  and overall  maximum  diameter  of  single  core  PVC  insulated 
(unsheathed)  cables  shall  be  as  per  the  values  given  in  table  4.  
5.7  Nominal  thickness  of  insulation,  nominal  thickness  of  sheath  and  overall  maximum  dimensions  of  
PVC  insulated  and sheathed  cables  shall  be  as  per  the  values   given  in  table  5.  
5.8  The  insulation  and  sheath  shall  consists  of  a  compound  based  on  any  one  of  the  following 
materials, which have been suitably compounded and processed to meet the requirements of this standard:  
                 a) Polyvinyl Chloride (PVC)  
                 b) Suitable  Co -polymer  of  which  the  major  constituent  shall  be  vinyl chloride.                                                                                                                                                                                                                                                                                  NS 344:2074  
8 
                  c) Mixture of polyvinyl chloride and Co polymer.  
5.9  Application  of  insulation : The  insulation  shall  be  applied  by  extrusion  process  so  that  it  fits  
closely  on  the  conductor  and  it  shall  be  possible  to  remove  easily  without  damaging  the  conductor.  
5.10  Tolerance  on  the insulation  thickness:  Measured  value  of  thickness  shall  not  be  less  than  by  
(0.1+0.1 t1)  of  values  given  in  table  4 and 5.  
5.11  Minimum  tensile  strength  and  minimum  percentage  elongation  at  break  of  insulation shall  be  12.5 
N/    and  150%  respectively.  
5.12 Core   identification:  
Cores shall be identified by diff erent coloring of PVC insulation.   Following color scheme shall be adopted.  
                    1 Core  -  Red,  black,  yellow,  blue,  white,  green,  or  grey  
                    2 Core -   Red and black  
                    3 Core -   Red, yellow, blue  
                    4 Core -   Red, yellow, blue and black  
5.13 Laying up of cores:  
5.13.1  Flat  twin  and  3 cores  cables (without  ECC)  -  2  or  3  cores  shall  be  laid  side  by  side.  
5.13.2  Flat  twin  (with  ECC)  cables :  Two  cores  with  a  bare  ECC  shall  be  laid  side  by  side  in  the  
same  plain, ECC  occupying  the  central  position.  
5.13.3  Circular  twin,  3  and  4  core  cables :  2,3  or  4  core shall  be  laid  together  with  a  suitable  right  
hand  lay.  The interstic es   between the  cores  may  be  filled  with  vulcanized  rubber,  thermoplastic  
materials  but  should  not  be  harder  than  PVC.  A  binder  tape  of  plastic  material  or  proofed  cotton  may  
be  applied  over  the  laid  up  cores  or  the  lai d  up  cores  shall  be  provided  with  inner  sheath  applied  
either  by  extrusion  or wrapping.  
5.14 Sheathing:  
5.14.1  The  sheath  where  applicable  shall  be  applied  by  extrusion.  It shall be applied  
             a)  Over insulation in case of  single core cables.  
             b)  Over the laid up cores in other cases.  
5.14.2  The  sheath  shall  be so  applied  that it  fits  closely  on  the  laid  up  cores   and  it  shall  be possible  
to  remove  it  without  damage  to the  insulation.  
5.14.3  Thickness  of  sheath :  Thickness  of  sheathing  shall  be  as  per  the  values  given  in  table  5.  
5.14.4  Tolerance  on  thickness  of  sheath -  Measured  thickness (ts)  on  the  table  5  shall  not  be  less  than  
by      (0.2 ts +0.2) mm . 
5.14.5  Sheath  color  -   The  color  of  sheath  shall  be mostly black or white  or  grey.  
5.15  During  flammability  test, the  period  of  burning  after  removal  of  flames  shall  not exceed  60 
seconds  and  charred  portion  from  the  lower  edge  of  the  top  clamp  shall  be  at  least  50 mm ( for  test  
method,  refer  to  NS 285 part 5).  
5.16  During  high  voltage  test  at  room  temperature,  the  cable  shall  withstand  an  AC  voltage of 3 KV  
(rms) at the frequency of  40 -60 Hz or  a DC voltage of 7.2 KV  between  conductor  and  ECC  ( if  any).  The  
connection  and  test  period  shall  be  as  per  the  table  6.  
NOTE:  For  single  core  cables  having  nominal  area  of  conductor  50       and  below,  this  test  is  not  
neces sary.  
5.17  During  spark  test,  cables  shall  not  fail  while  applying  test  voltage  corresponding  to  table 7.                                                                                                                                                                                                                                                                                  NS 344:2074  
9 
 NOTE:  Spark  test  is  done  as  an  alternate  to  high  voltage  test  on  single  core  unsheathed  cables.  
5.18 Insulation resistan ce constant:  Minimum insulation resistance constant shall be as follows:  
           At 27°C:  36.7 M ohm  km 
           At 70°C:  0.037 M ohm km  
5.19 PVC multi strand cable : It shall be constructed as given in Table 2 and Table 4.  
5.20 Test requirements for PVC insulation shall be as per the values given in table 9.  
5.21 Test requirements for PVC sheath shall be as per the values given in table 10.  
 
6 SAMPLING AND TESTING  
6.1 Sampling from  Lot :  Cables  with  similar  annealed   high  conductivity  coppe r  conductors  and  the  same  
cross  sectional  area  and  similar  configuration,  having  the  same  insulation  and   sheathing (if any ),  
manufactured  under  the  identical  condition  and  submitted  for  a  test  at  a  time  shall   constitute  a   lot.  
Required number of samples shall be collected randomly as given in Table 8.  
6.2 Types  of tests:  
6.2.1 Routine tests:  
         -    Resistance test of conductor  
          -    High voltage test / Spark test  
6.2.2 Acceptance Tests:  – Test shall be carried out as per NS 285.  
- Annealing  test  of  conductor  
- Resistance  test  of  conductor  
- Thickness  and  overall  dimensions  of  insulation  and  sheath  
- Tensile strength and percentage elongation of insulation and sheathing.  
- Insulation  resistance test  
- High voltage / Spark  test  
- Flammability test  
6.2.2.1  For  each  test  under  general  requirements ( clause 5.1)  and  Acceptance  Tests  ( Clause  6.2.2)  
samples  shall  be  selected  as  per  the  table  8.  
6.2.3 Type Tests:  
a) Test on conductor:  
         -    Annealing test of conductor  
         -    Resistance test of conductor  
b)   Test for overall dimensions and thickness of insulation and sheath  
 
 
 
c) Physical test for insulation:  
         -    Tensile strength and percentage elongation at break  
         -   Loss of mass test                                                                                                                                                                                                                                                                                  NS 344:2074  
10 
          -   Ageing in air oven  
         -   Shrinkage test  
         -   Heat shock test  
         -   Hot deformation  
d) Physical test for sheath:  
        -   Tensile strength and percentage elongation at break  
        -   Loss of mass test  
        -   Ageing in air oven  
        -   Shrinkage test  
        -   Heat shock test  
        -   Hot deformation  
e) Test on completed cable:  
      - High voltage test (water immersion test)  
      - High voltage test/Spark test  
      - Insulation resistance  
      - Flammability test  
      - High voltage test  
6.2.3.1  For each  characteristics  mentioned   under  6.2.3  (Type  test)  appropriates  samples  shall  be  taken  
and  tested .If  the  sample (s)  fails  in  any  one  of  the  tes t,  one  more  sample  shall  be  subjected for  retest,  
which  should  pass.  
 
7   CRITERIA FOR CONFORMITY    
7.1   The  lot  shall  be  considered  acceptable  if  the  samples  selected  as  per  the  column  2  of  the table 8  
satisfy  each   and  ever y   requirements   under  the  clause  4  not  exceeding  the  defectives as  per  column  3  
of  table  8.  
 
8 MARKING AND LABELLING  
8.1 The  cable  shall  be  either  wound  on  drums,  reels  or  coils,  properly  packed.  
8.2  The  cable  shall  carry  t he  following  information  either stenciled  on  the  reels  or  drums  or  contained  
in  a  label attached to it:  
a) Industry’s name and trade name and / or trade mark, brand name.  
b) Nominal   cross  sectional  area  
c) Configuration   (i.e.  Number of wires, co res etc.)  
d) Batch  number  
e) Length  of  cable  and  number  (  if  more  than  one )  
f) Approximate  gross  weight  ( if in drum)  
g) Country  of  manufacture  
h) Year  of  manufacture  
i) Voltage  rating                                                                                                                                                                                                                                                                                  NS 344:2074  
11 
 j) Color of core (in case of single core cables)  
k) Cable code (Provision for cable code is given in clause 3.8)  
l) Direction of rotation of drum (by means of arrow)  
m) Type of cable and material of conductor  
8.3 Every meter of each cable shall contain following information’s:  
        a) Diameter of strand  
        b) Number of strand  
        c) Nominal cross sectional area  
        d) Sequential running meter  
        e) Batch number (optional for cable having nominal cross sectional area above 25 mm2) 
        f) Industry’s name and trade name and / or trade mark, brand name  
 
 
9   PACKAGING  
9.1 Following information’s must be included:  
            a) Total length of the wire  
b) Diameter of strand  
c) Number of strand  
d) Nominal cross sectional area  
e) Industry’s name and trade name and / or trade mark, brand name  
 
                            
 
 
 
 
 
 
                       
 
 
 
 
                                     
 
 
 
                                                                                                                                                                                                                                                                                 NS 344:2074  
12 
   Table 1: Circular wire  
 Diameter  Calculated 
area (   ) 
 
 
(3) Nominal 
weight(kg/km)  
 
 
(4) Resistance per km.at 20°C (ohm)  
 
Standard 
(mm)  
(1) Tolerance 
(mm)  
 (2) Standard  
 
(5) Maximum 
for plain 
wire (6)  Maximum for 
tinned wire  
(7) 
0.2000  
0.3000  
0.4000  
0.4500  
0.5000  
0.5200  
0.5500  
0.6000  
0.6100  
0.6500  
0.6750  
0.7120  
0.7500  
0.8130  
0.8500  
0.9140  
1.0160  
1.0200  
1.0600  
1.1200  
1.2200  
1.4000  
1.6300  
1.7000  
1.8000  
2.0600  
2.1400  
2.2400  
2.3400  
2.5000  
2.8000  
3.0000  ± 0.0050  
±  0.0070  
±0.0090  
± 0.0090  
±0.0090  
±0.0090  
±0.0090  
±0.0100  
±0.0100  
±0.0100  
±0.0100  
± 0.0100  
± 0.0120  
± 0.0120  
±  0.0120  
± 0.0140  
±0.0160  
±0.0160  
± 0.0160  
± 0.0160  
± 0.0160  
± 0.0160  
± 0.0200  
± 0.0200  
± 0.0250  
± 0.0250  
± 0.0250  
± 0.0250  
± 0.0280  
± 0.0300  
± 0.0300  
± 0.0300  0.0314  
0.0707  
0.1257  
0.1590  
0.1963  
0.2124  
0.2376  
0.2827  
0.2922  
0.3318  
0.3575  
0.3980  
0.4420  
0.5190  
0.5680  
0.6560  
0.8110  
0.8171  
0.8830  
0.9850  
1.1690  
1.5390  
2.0870  
2.2700  
2.5450  
3.3300  
3.5980  
3.9410  
4.3010  
4.9090  
6.1580  
7.0690  0.2800  
0.6300  
1.1200  
1.4000  
1.7500  
1.8900  
2.1100  
2.5100  
2.6000  
2.9500  
3.1800  
3.5400  
3.9300  
4.6200  
5.0400  
5.8300  
7.2100  
7.2100  
7.8500  
8.7600  
10.3900  
13.6800  
18.5600  
20.1800  
22.6200  
29.6300  
31.9700  
35.0700  
38.2400  
43.6400  
54.7400  
62.8400  548.7300  
243.9000  
137.1600  
108.4300  
87.8300  
81.1700  
72.5600  
60.9900  
59.0000  
51.9600  
48.2300  
43.3000  
39.0300  
33.2100  
30.3800  
26.2700  
21.2600  
21.1000  
19.5200  
17.5000  
14.7500  
11.2000  
8.2600  
7.6000  
6.7800  
5.1700  
4.7900  
4.3800  
4.0100  
3.5100  
2.8000  
2.4400  565.1900  
251.2200  
141.2700  
111.6800  
90.4600  
83.6100  
74.7400  
62.8200  
60.7700  
53.5200  
49.6700  
44.6000  
40.2000  
34.2100  
31.2900  
27.0600  
21.9000  
21.7200  
20.1000  
18.0300  
15.1900  
11.5400  
8.5100  
7.8300  
6.9800  
5.3300  
4.9300  
4.5100  
4.1300  
3.6200  
2.8800  
2.5100  576.1700  
256.1000  
144.0200  
113.8500  
92.2200  
85.23S00  
76.1900  
64.0400  
61.9500  
54.5600  
50.6400  
45.4700  
40.9800  
34.8700  
31.9000  
27.5800  
22.3200  
22.1400  
20.4900  
18.2000  
15.3300  
11.6500  
8.5900   
7.9000  
7.0400  
5.3800  
4.9800  
4.5600  
4.1700  
3.6500  
2.9100   
2.5400                                                                                                                                                                                                                                                                                  NS 344:2074  
13 
 Note:  
1 .Resistivity of cu is taken as 0.017241 micro ohms. (    )/mtr  
2. The values given in column 6 are based on +3% to the values given in column 5; the values given in column 
7 are based on +5% up to 1.12 mm and +4% above 1.12 mm to the values given in co lumn 5.  
3. The values given in nominal weight column is only for guidance.  
  
                   
                    
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
                                                                                                                                                                                                                                                                                   NS 344:2074  
14 
                      Table 2: Stranded conductors for single core and multi core cables  
 
1 2 3 4 5  
Nominal  
cross 
sectional 
area  
mm² Minimum number of wire in the 
conductor  Maximum resistance of conductor 
at 20° C    
 
Circular 
conductor  Circular 
compacted 
conductor  Shaped 
conductor  Annealed copper conductor  
Plain 
wires  
Ohm/km  Tinned  wires  
Ohm/km  
Cu Cu Cu 
0.50 
0.75 
1.00 
1.50 
2.50 
4.00 
6.00 
10.00  
16.00  
25.00  
35.00  
50.00  
70.00  
95.00  
120.00  
150.00  
185.00  
240.00  
300.00  
400.00  
500.00  
630.00  7 
7 
7 
7 
7 
7 
7 
7 
7 
7 
7 
19 
19 
19 
37 
37 
37 
61 
61 
61 
61 
91 - 
- 
- 
6 
6 
6 
6 
6 
6 
6 
6 
6 
12 
15 
18 
18 
30 
34 
34 
53 
53 
53 
 - 
- 
- 
- 
- 
- 
- 
- 
- 
6 
6 
6 
12 
15 
18 
18 
30 
34 
34 
53 
53 
53 36.0 
24.5 
18.1 
12.1 
7.41 
4.61 
3.08 
1.83 
1.15 
0.727  
0.524  
0.387  
0.268  
0.193  
0.153  
0.124  
0.0991  
0.0754  
0.0601  
0.0470  
0.0366  
0.0283  36.7 
24.8 
18.2 
12.2 
7.56 
4.70 
3.11 
1.84 
1.16 
0.734  
0.529  
0.391  
0.270  
0.195  
0.154  
0.126  
0.100  
0.0762  
0.0607  
0.0475  
0.0369  
0.0286    
         
Note:  The diameter and tolerance of individual strand shall comply with any one of the suitable diameter and 
tolerance of wires stated in table 1 of this standard.  
                          
                                                    
                                           
 
                                                                                                                                                                                                                                                                                 NS 344:2074  
15 
                                                  Table 3: Annealing test  
 
Wire   Diameter  
                     (1) Minimum Elongation  (%)        
(2) 
Up to  and  including                           0.14 mm  
Above 0.14 mm up to and including   0.20 mm  
Above 0.20mm up to and including    0.45 mm  
Above 0.45 mm up to and including   1.12 mm  
Above  1.12 mm                 5.5 
               9.0 
13.5 
18.0 
22.5 
 
 Note :  Minimum percentage elongation is applicable for the wires having joint(s) also.  
                          
                                  Table 4: Single core PVC insulated (unsheathed)  
 
     
 Nominal cross sectional area 
of conductor      
 (1) Thickness of insulation 
(t1) mm  
(2) Maximum overall diameter                  
mm  
(3) 
0.50 0.6 2.3 
0.75 0.6 2.5 
1.00 0.7 3.2 
1.5 0.7 3.4 
2 0.7 3.6 
2.5 0.8 4.2 
4 0.8 4.8 
4.5 0.8 5.2 
6 0.8 5.6 
8 0.9 6.2 
10 1.0 7.0 
15 1.0 7.8 
16 1.0 8.2 
25 1.2 10.0 
35 1.2 11.5 
50 1.4 13.0 
70 1.4 15.0 
95 1.6 17.5 
120 1.6 19.0 
150 1.8 21.0 
185 2.0 23.5 
240 2.2 26.5 
300 2.4 29.5 
400 2.6 33.5 
500 2.8 37.5 
630 2.8 42.0                                                                                                                                                                                                                                                                                 NS 344:2074  
16 
                                       
                                            Table 5: PVC insulated and sheathed cables  
 
Nominal  
area of 
conductor  
mm² 
 
 
(1) Nominal 
thickness 
of 
insulation 
t1  (mm)  
(2) Nominal thickness of sheath (ts)  Nominal 
area of 
ECC  
(mm)  
 
(7) Maximum overall dimensions  
Single 
core 
(mm)  
(3) Two 
core 
(mm)  
(4) Three 
core 
(mm)  
(5) Four 
core 
(mm)  
(6) Single 
core 
(mm)  
(8) Twin 
core 
(mm)  
(9) Three 
core 
(mm)  
(10) Four 
core 
(mm)  
(11) Flat twin 
without 
ECC (mm)  
(12) Flat twin 
with 
ECC(mm)  
(13) Flat three 
without 
ECC(mm)  
(14) 
1.0 
1.5 
2.5 
4.0 
6.0 
10.0 
16.0 
25.0 
35.0 
50.0 0.6 
0.6 
0.7 
0.8 
0.8 
1.0 
1.0 
1.2 
1.2 
1.4 0.8 
0.8 
0.8 
0.9 
0.9 
0.9 
1.0 
1.1 
1.1 
1.2 0.9 
0.9 
1.0 
1.0 
1.1 
1.2 
1.3 
1.4 
1.5 
1.6 0.9 
0.9 
1.0 
1.1 
1.1 
1.2 
1.3 
1.5 
1.6 
1.7 0.9 
0.9 
1.0 
1.1 
1.2 
1.3 
1.4 
1.6 
1.7 
1.8 1.0 
1.5 
1.5 
1.5 
2.5 
4.0 
6.0 
- 
- 
- 4.7 
5.0 
5.8 
6.8 
7.8 
8.8 
10.5 
12.5 
13.5 
15.5 8.2 
8.8 
10.5 
12.0 
13.5 
16.5 
19.0 
23.0 
25.5 
29.5 8.6 
9.2 
11.0 
13.0 
14.5 
17.5 
20.0 
24.5 
27.5 
31.5 9.2 
10.0 
12.0 
14.0 
15.5 
19.5 
22.5 
27.5 
30.5 
35.0 7.8*5.0  
8.4*5.4  
10.0*6.4  
11.5*7.2  
13.0*8.0  
16.0*9.6  
18.5*11.0  
22.5*13.0  
25.5*14.5  
29.0*16.5  9.2*5.0  
10.2*5.4  
12.0*6.4  
13.5*7.2  
15.5*8.0  
19.0*9.6  
22.0*11.0  
- 
- 
- 10.5*3.0  
11.5*5.4  
14.0*6.4  
16.5*7.4  
18.0*8.0  
22.5*9.6  
26.5*11.0  
32.5*18.5  
36.0*15.0  
41.5*17.0  
 
                                                                                                                                                                                                                                                                                 NS 344:2074  
17 
                           
                                    Table 6: High voltage test - connections and test period  
 
Type of cable  Connection diagram  Test connection  Test period 
(minute)  
Single core   1 against  E  5 
Two core  
  
 1 against  2 + E  
2 against 1 + E  5 
5 
Total =10  
Three core  
 
  
 
 1 against 2+3+ E  
2 against 3+1 +E  
3 against 1 + 2+E  5 
5 
5 
Total =15  
Four core  
  
 1 +2 against 3+4 +E  
1+3 against 2+4 +E  
 1 + 4 against 2+3 +E  5 
5 
5 
Total =15  
 
 
Note 1: E –Earth  
Note 2: For multi core cables, voltage test shall be done between the conductor and free core bunched 
together and earthed as shown above.  
Note 3: For single core cables, voltage test shall be done between the conductor and the tank with the 
cable under water.  
Note 4: During high voltage test, one pole of power source shall be earthed.  
 
 
 
 
 
 
 
 
 
 
1 
1 
2 
2 
3 
1 
a 
4 
 3 
1                                                                                                                                                                                                                                                                                 NS 344:2074  
18 
  
 
                                           Table 7:    Spark test  
 
 
           Insulation thickness   
Test voltage  KV (rms)  
 
Up to and including                          1 mm  
Above 1 mm and up to including   1.5 mm  
Above 1.5 mm and up to including 2.0 mm  
Above 2.0 mm and up to including 2.5 mm  
Above 2.5 mm   
6 
10 
15 
20 
25 
 
 
 
 
 
                                                      Table 8:  Sampling of cables  
 
Number of drum/reel/coil in a 
lot Number of drum/reel/coil to be taken 
as sample  Number of permissible 
defectives  
Up to 25  
26 – 50 
51 – 100 
101 – 300 
Above 300  3 
5 
8 
13 
20 0 
0 
0 
1 
1 
   
  
 
 
 
 
 
 
 
 
 
                                                                                                                                                                                                                                                                                 NS 344:2074  
19 
                                  Table 9: Test requirements for PVC insulation  
S.N.    Test Unit Type of 
insulation       
(A) Methods of 
tests 
 1 Insulation resistance constant, Min  
    a) at 27°C   
 
M ohm km   
 
36.7   
 
Refer  
 NS 285  
Part 1      b)at maximum rated temperature   
M ohm km  
  
0.037  
2 Without ageing  
a) Tensile strength, Min   
N/     
12.5  
Refer  
NS 1* ….. b) Elongation at break, Min  Percent  150 
3 After ageing in in air oven  
     a)Treatment  
     -Temperature(tolerance ±2°C)  
 
    - Duration   
 
°C 
 
Days   
 
80 
 
7  
 
 
 
 
 
Refer  
 NS 2*   …..      b)Tensile strength  
       -Value after ageing, Min  
      - Variation , Max   
N/    
Percent  
  
12.5 
±20 
c)Elongation at break  
    - Value after ageing, Min  
    -Variation ,Max  
  
Percent  
Percent  
  
150 
±20 
4 Loss of mass in air oven  
    Treatment  
   -Temperature(tolerance ± 2°C)   
 
       °C   
 
80  
 
 
 
Refer  
NS 3* …...  
   
  - Duration  
 
       
      Days   
7 
5 Hot deformation test(pressure at 
high temperature)  
  a)Test temperature  
       (tolerance ±2°C)   
°C 
  
80 
  
Refer NS 
285 part 4  
                                                                                                                                                                                                                                                                                 NS 344:2074  
20 
   b)Time under load  
     -first case  
     -second case  
c)Depth of indentation, Max  
  
Hours  
Hours  
Percent  
  
4 
6 
50 
6 Heat shock test  
  a)Treatment  
     -Temperature(tolerance ±2°C)  
    - Duration  
b)Visual examination   
 
°C 
       Hours  
-  
 
150 
           1 
- 
  
 
 
Refer  
 NS 4* ….. 
 
7 Shrinkage test  
a)Treatment - 
 -Temperature( tolerance ± 2°C)  
 - Duration  
b)Shrinkage, Max  
  
 
°C 
    Minutes  
Percent   
 
150 
          15 
4  
 
Refer  
 NS 5*…...  
 
Note:  
The type of PVC compounds covered by this standard is given below:  
1. Type A – General purpose insulation for maximum rated conductor temperature 70°C intended for cables 
with rated voltages Uo/U up to and including 3.3/3.3KV.  
2. Type ST1 – General purpose sheath intended for use in cables operating at a maximum rated conduc tor 
temperature 70°C.  
 
 
 
 
 
 
                                            
                                      
 
 
 
 
 
                                                                                                                                                                                                                                                                                               NS 344:2074  
21 
                             Table 10: Test requirements for PVC sheath  
S.N.    Test Unit Type of 
sheath(ST1)  Methods of tests  
1 
 
 Without ageing  
     a) Tensile strength, Min  
     b) Elongation at break, Min   
N/    
Percent   
12.5 
150  
Refer  
NS 1* ……     
 
2 
 
 
 
 
 
 After ageing in air oven  
a) Treatment  
         -Temperature (tolerance ±2°C)  
         -Duration  
b)Tensile strength  
         - Value after ageing, Min  
          -Variation, Max  
 c)Elongation at break  
          -Value after ageing, Min  
          -Variation, Max   
 
°C 
Days  
 
N/mm2 
Percent  
 
Percent  
Percent   
 
80 
7 
 
12.5 
±20 
 
150 
±20  
 
 
 
Refer  
  NS 2* ….. 
3 Loss of mass in air oven  
a) Treatment  
          - Temperature (tolerance ± 2°C)  
          - Duration  
b)Loss of mass, Max   
 
      °C 
Days  
Mg/cm2  
 
80 
7 
2  
 
Refer  
  NS3* …….  
4 Hot deformation test(pressure at high 
temperature)  
     a) Test temperature (tolerance ±2°C)  
     b) Time under load  
                  First case  
                  Second case  
c)Depth of indentation, Max   
 
°C 
 
Hours  
Hours  
Percent   
 
80 
 
        4 
6 
50  
 
Refer  
  NS 285 part 4  
5 Heat shock test  
a) Treatment  
          - temperature (tolerance ± 2°C)  
          - Duration  
b)Visual examination   
 
    °C 
  Hours  
      -  
  
150 
1 
-   
 
Refer  
  NS4*……                                                                                                                                                                                                                                                                                  NS 344:2074  
22 
 6 Shrinkage test  
a) Treatment  
         - temperature (tolerance ± 2°C)  
         - Duration  
b)Shrinkage, Max   
 
°C 
Minutes  
Percent   
 
150 
15 
4  
 
Refer  
 NS5* ……  
 
Note:  
NS 1* ….. –Until the relevant Nepal Standard will be developed for both insulation and sheath testing, refer IS 
10810, part 7.  
NS 2* …… - Until the relevant Nepal Standard will be developed for both insulation and sheath testing, refer IS 
10810, part  11. 
NS 3* …… - Until the relevant Nepal Standard will be developed for both insulation and sheath testing, refer IS 
10810, part 10.  
NS 4* ……. -Until the relevant Nepal Standard will be developed for both insulation and sheath testing, refer IS 
10810, part 14. 
NS 5* ……. -Until the relevant Nepal Standard will be developed for both insulation and sheath testing, refer IS 
10810, part 12.