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IS 3722-2 (1983): Letter symbols and signs used in
electrical technology, Part 2: Reference tables for symbols
and subscripts [ETD 1: Basic Electrotechnical Standards]
 
 
Standard
AND S IG NS U S E D IN
E L E C TR IC AL TE C H NOL OG Y
PART2 REFERENCE TABLES FOR SYMBOLS AND
SUBSCRIPTS
B a sic E lect rot echnica l S t a nda rds S ect iona lC omfit t ee, E DC 1
Ch4irman
15, 1S1
Delhi
SE W T. L. B HATI
I ndia n P ost s a nd Telegra phs D epa rt m ent
( M in is tr y of C ommunica t ions ), New D elhi
S EIRIJ . L. BANDOP.\DliYAY Alternate )
SHRI V. S. BHATIA
Oommittee, ETDC 57, 1S1
CEAIRISAN
S econ da ry C ells a nd B a t teries S ect iona l C om mit tee,
E TD G 11, 1S 1
B B X G N . DAYAL
Institution of Engineers India ), Oalcutta
DXRECTORSTANDAKDS ELECTRK-
D I ~ E C TO B (TE D )
C ent ra l E lect r icit y y Aut hor it y , D epa rt ment Of
P ow er (hfin ist ry of E nergy), New D elhi
13EFLTTYDIR IOG ~ OR,TED ) ( Akwale )
S H R I M. L. D OIWJ RS P ow er C a bles S ect iona l C om mit t ee, E TD C 59, 1S 1
S H RI R . D . J AI N C onduct ors a nd Accessories for Overh ea d Lines
S ect iona l Oommit t ee. E TD C 60, 1S 1
S HRI S. K. KAS LI WA~
B ha ra t H ea vy E lect r ica ls’Lt d, B hopa l
S E m PRAK AS H S IS ~ H ( Alternate )
SH RI S . K . MLXIIE EJ E X
N“a t ion a l Test H ou se, C a lcu tt a
S riRx B . MU KI IOP AD EYAY ( Alfernutt
  Cont inuedon ~ age 2
~ C o r ight 984
I ND IAN S TAND ARD S INS TITU TI ON
This publica t ion is prot ect ed un der t he Indian C @right Act ( XIV of 1957) a nd
 
 
S EIS I D . N. P U RAX~ ARE
SH RI V. L. S AS ITRY
S H E IK . V. B E AT (
Alfernatt )
C OL K . V. KC TIWA (
Afternate )
SH RI H . N. VE IVKOB XARAO
Re resent in g
Rela ys S ect iona l C ommit t ee, E TD C 35, 1S1
H igh Volt a ge S w it chgea r a nd C ont olgea l
S ect iona l C ommit t ee,. E TD C 58, IS I
E lect r ica l Wir in g Acces sor ies S ect ion a l C om mit t ee,
E TD C 44, 1S 1
E lect ronics a nd Ra da r D evelopment E st a blish-
ment ( Minist ry of D efen ce j, B a nga Iore
Minist ry of D efen ce ( D G I )
~ e~ ;rmers S ect iona l C ommit t ee, E TllC 16, 1S1
Electrochemical
Resea rch Inst it ut e
(C SI R), K ara ikudi
S HRI Y. MAH AD EVA IYB R ( A[fema & j
&iI U M. P . WAG E
India n E lect rica l Ma rmfa ct urers’ Associa t ion,
Bombav
S H H I S. D . ME D E E IIAR (
Alfernaf6 ) ‘
S H R I S. P. SACStDET,
D irect or G en era l, 1S 1 ( E x.oficio
Mem6sr )
D irect or ( E lec t ech ) ( &cw a ry )
2
hdian Standard
LE TTE R S YMB OLS AND S IG NS U S E D IN
E L E C TR IC AL TE C H NOL OG Y
PART 2 REFEREKETABLESFORSYMBOLSAND
  First Revision
O. FOREWORD
0.1 This In dia n S t a n da r d ( First Revision ) ( P a r t 2 ) w a s a do t ed by t he
i?ndia n S t a nda rds Inst imt ion on 30 Ma y 1983, a ft er t he dra ft na lized by
t he B a sic E lect rot echnica l S t a n da r ds S ect iona l C ommit t ee ha d been
a ppr oved by t he E lect rot echn ica l D ivision C oun cil,
0.2 Qua nt it ies a nd unit s used in elect ica l t echnology cover , in a ddit ion t o
lect r icit y , m a gn et ism , mdi a t ion a n d ligh t, ot her subject s such a s geomet ry,
kin em a tics, d yn a mics a n d t her mody na m ics.
As t ech nolog y r ca ch e.s g rea t er
levels, severa l disciplines in t era ct w it h t he result t ha t t erminology used in
one discipline becomes closely in t errela ted w it h t ha t of t he ot her.
The
let t er sy mbols, used in a bbr evia t ion s for den ot in g q ua n tit ies, t heir fun ct ion s
a nd unit s, t herefore. w ould ha ve t o be st a nda rdized in order t o ena ble
uniform un derst an ding of t he mea ning t hey r epresen t.
0.3 Rea iising t he need, t h is st a nda rd w as origina lly brought out in 1966
essent ia lly t o cover symbols or qua nt it ies a nd unit s. The present revision
is being brought out w it h a w ider scope, including rules for subscr ipt s,
rules for denot ing numerica l va lues et c. This revision for ea se of reference,
is being brought out in t w o pa rt s:
P a rt 1 G enera l guida nce on symbols a nd subscr ipt s
P a rt 2 Reference t a bles for symbols a nd subscr ipt s
I t is felt t ha t w hile P ar t 1 essent ia lly w ould provide guida nce on
choice of symbols a nd subscr ipt s w it h t he a ssocia ted logic, P a r t 2 w ould
serve a s a rea dy reference on t he va r ious q urmt it i es a n d unit s. These
Parts sh a ll, t her efor e, be r ea d in con jun ct ion with each other.
3
IS : 3722 ( Part 2 ) - 1983
0.4 In this standard the units are given in the SI units ( the International System of Units .  This system is based on the following six basic units:
metre ( m ) ampere ( A )
kilogram ( kg ) kelvin (k)
second ( s )
candela ( cd )
as units for the basic quantities of length, mass, time, electric current, temperature, and luminous intensity. For some of the quantities, like conductance and magnetic flux density, the units are given, besides in SI units, also in more familiar units in use in the country. However, it should be noted that the latter units are not necessarily equivalent to the SI units.
0.5 In the preparation of this standard, considerable assistance has been derived from IEC Pub 27-I 197   1) ‘Letter symbols to be used in electrical technology :  Part I General’, issued by the International Electrotechnical Commission.
1. SCOPE
1.1 This standard covers letter symbols and signs for quantities used in electrical technology and their units.
1.2 This standard ( Part 2 ) covers reference tables for symbols for quantities and their units, constants, methematical   signs and symbols and recommended subscripts.
2. INTRODUCTION TO TABLES
2.1 The tables in the following pages include in addition to certain symbols used in electricity and magnetism, some other symbols that occur in electrical technology.
2.2 In Table 1 the vectorial or tensorial character of certain quantities or their complex representation are disregarded.
2.3 The first column of symbols for quantities in Table 1 gives the chief symbols. The second column gives reserve symbols for use where a chief symbol is found unsuitable, for instance where its use would lead to confusion with the same symbol used with a different significance.
2.4 Names are used only for identification, and generally agree with I S : 1885*.
l Electrotechnical vocabulary ssus in several parts
4
1S :3722 ( Part 2 ) .1383
2.5 W’her ever t hesy rn bo lfort heunit is I , t he cor responding q ua nt it y isa
numeric a nd it s va h e is w r it t en a s a number w it hout t he unit symbol.
Wherever t he na me of a unit is of t he form ‘l per met rc’, q ua nt it ies a re
expressed in t he form ‘x per xnet re’ w here x is t he numerica l va lue, for
exa m ple, 5 per m et re,
2.6 Rules for the choice of subscripts are given in IS :3722 Part 1 )-
1983*. S ubscr ipt s sha ll conform t o t hese rules, but even w hen t hey do, a
ch oice bet w een differ en t su bscr ipt s for t he sa m e pur pos e is n ot pr eclu ded.
As a help t ow a rds st a nda rdizing t he choice, a list of subscr ipt s r ecom men-
ded for va rious purposes is given in t he Ta ble 4. These subscript s a re
recommended for use irrespect ive t he la ngua ge of t he t ext in w hich t e
s ym bols a p pea r .
2.7 Let t er symbols for q ua nt it ies or unit s a re recommended for use a s
subscr ipt s w henever a pp ica ble, a nd since t hese a re w ell know n a nd int er -
n a tion a lly u nd er st ood t hey h a ve n ot been specifica lly list c d h er e.
2.8 The subscr ipt s specified in Ta ble 4 a re given in a list divided int o
groups w it h some mor e or less discern ible r ela t ionship w it hin ea ch group.
T e order bet w een t he grou s a nd w it hin t he groups is not significa nt . In
fenera l, a shor t form a nd a ong form of subscr ipt is given for ea ch it em.
T e long form is in t ended t o e I ess a mbiguous t ha n t he shor t one.
2.9 I n t he la st column of Ta ble 4 t he la ngua ge source is indica ted by ‘L’
for La t in, ‘G ’ for G reek, ‘E ’ for E nglish, a nd ‘F ’ for F rench. I f t here a re
m any sour ces for t he sa me subscr ipt , in gener al only on e is men tioned.
3. ALPHABETICAL LISTS
3.1 Alpha bet i a l list s of symbols, a nd na mes of q ua nt it ies, const ant s a nd
subscr ipt s, cor responding t o Ta bles 1 to 4 a re given in Appendices A, B ,
C a nd D for t he purpose of ea sy reference.
 Let t er symbols a nd signs used in elect r ica l t echn ology: P ar t 1 G en era l guida nce on
symbols a nd subscr ipt s ( ~ rst r@ion ).
5
Q UANTITIES UNITS - -
“
angle) letters of the minute . . . ’  Note 1 Greek alphabet   second . ”
- -  
 
5 height, depth h metre   m - - - -
6   thickness   d 6
 
Q U A N T I T I E S I
UNITS
 
 
+
Table 2
I  I
second
acceleration due second to gravity
1 per second s-1
 ~
in general, units are used only with L and p
see
Note 6
A
C
G
53 surface density of u
charge
i5 6
 
heat capacity divided by mass; the term ‘  specific heat ’  is depreca- ted
x
changes is speci- fied, for example, resistance, length, pressure ; the pressure ( tempe- rature coefficient is designated by B,
the cubic expansion tem-
or Y
Electricity and Magnetism
56
57
fl
SI unit
electromotive force
58 volt
coulomb per square metre
 De l e c t r i c f l u x density, displace- ment
capacitance61 farad
62
63
for so  see Table 2 farad per metrepermittivity, abso lute permittivity ( capacitivity )
relative permitti-
- - - -
- -  
- - - - ampere
metre - - - -
69 linear current  A a current divided density by width of the
conducting sheet - - - -
strength Note 8 - - - -
71 m a g n e t i c poten- U,
ampere
force Gb see Note 10
- - - -
NZ
( Continued )
80 permeability,   IL
for ~0   see Table 2 henry per metre   H/m absolute permea- bility
81 relative permea- ur
the vector product ampere square A.ms
- -
- -
85 intrinsic magnetic Bf, J Bi=B poH tesla T flux density, mag- netic polarization
- - 86 magnetic dipole j
87   resistance R  see Item 93 ohm   n
. - -
- -
90
- - conductivity
92 I
I
QUANTITIES UNITS  
_
 
P
is sometimes used to indicate number of poles. Where ambiguity may occur, the intended mean- ing should be indicated  
Radiation
radiant energy
r a d i a n t f l u x , radiant power
radiant intensity
 
REMARK
YMBOL
 
S “806 65 m ls ~
IQ
I 20’2
s ta n da rd a cceler at ion of f ree fa ll
( 1602192 + 0“00007 ) X 10-19C
203
el em en t a ry ch a rg e
e
h = + ~ ; = ( 1’054592 & 0’000008 )
X 10-34J . s
P l a n ck con s ta n t
B ol tz ma n n ccn st a nt
( 138062 & 0“00006 ) X 10-z3J /K
elect ric con st an t,
permittivity
( 8 “854 185 + 0“000 006 ) x 10-12 F /m
4T x 10-7 H /m= 1”256 64x 10–6 H m
a gn et ic con st a nt , per mea bil it y
of v a cu um
COPO = -+
co
1
207
I
208
F ( 9 .64867+ 0“000 16) x 10~ C )mol
( 9“ 10956+ 0“00005 ) X 10-31 kg
( 9“27410 + 0“00006 ) X 10-Z4J I T
209
210
m
 
 
ITEM
NAME
S I G N O R C B ] E F
No.
SYMBOL
REMARKS
301
or din a ry d if fer en t ia l s ig n
d
3
8
304
A
305
z
306
r I
307
ba se of n at ur al loga rit hm s
e
308
of a cir cle
j
310
2
. 2,X
T
a
*>Y>~
312
cy l in d ri ca l co -o rd in a t e s
(ds)z= ( dp)z+ (pdq )~ + (dz)’
r , 0, @
(rsin$dq )9
I
( see 2.9 )
  1 1
optical
acoustical
radiation
ch
e
e
m
m
m
Kind of Value of a Quantity
root -mea n-sq ua re ( va lue of a per iodic q ua nt it y )
pea k v alu e
ma ximum ( not in t he sense o fpea k va lue )
a vera ge ( a rit hm et ic m ea n va lue )
median
m ed
L
SUBJECT
SUBSCRIPT
n eg a t iv e s eq u en ce com pon en t
resonance
signal
distortion
i
L a ng ua g e S ou rce
2
r
su m
equivalent
s y nc hr on ou s , s y n ch r on i zi n g
asynchronous
time
simultaneous
successive
self
longitudinal
direct ( for exa mple, a xis in elect rica l ma chine
t heory )
parallel
spherical
hemispherical
ambient
L
L
L
L
L
a
r
t
1
d
-
* ,S eeTa b le 5, f or il lu st r a t iv e ex a mpl es .
t When, in t he sa me cont ext dif ference a nd different ia l a re used
d if fer en ce a n d ‘ d ‘ for d i fferent ia l .
.—
 
 
static
dynamic
0702 out, output   2,  ex,
0703 primary 1,P
 
E,  F
L
G
L
L
G
L
L
L
L
L
L
L
L
G
 
 
ITEM
Short Form
0808   cathode   k G
0102 electric energy
0104 magnetic energy
0106 mechanical energy
We el
Rrns
*There is no alternative subscript, since this entire symbol has been standardized.
29
SYXBOL
I TE M N a MB E R I N TAB L E
( Q U AN TI TI E S )
AND
2
44, 54
(
IN TABLE 1
ARLE 1
TAB LE 1
27, 28, 29
NAME
I
a bs olu te per mit t ivit y
a bsolut e t em per a tur e
acceleration
gr av i ty
a ct ive pow er
ad mi t t anc e
angle
a ngula r velw it y
a ppa rent pow er
area
a t t e n ua t i on coef fi ci en t
Avoga d ro const a nt
bla ck body ra dia tion
boh r m a gn et on
B olt zma rm onst a nt
breadth
charge
1on uct ance
cu bic expa n si n
(t em per a t ur e ) coeffi-
cient
current
(CONSTANTS
21
1c)
density
depth
diameter
displacement
dyna mic moment of
elect r ic con st a n t
elect r ic cu rr en t
elect r ic di ole om ent
Ylect ric fle d st rengt h
elect r ic flu x
elect ric flu x d en sit y
elect r ic pola r iz a t ion
elect r ic pot en tia l
el ect r i c s us cept i bi li t y
electrization
ment
elem en ta r y ch a rge
energy
flu x of d is pla cem en t
force
frequency
heat
h ea t ca pa cit y
height
illuminance
impedance
int r insic ma gnet ic flux
density
irradiance
l ea k a g e coe ff ici en t
length
lin e s eg m en t
l in ea r a c ce ler a t i on
lin ea r cu rr en t d en sit y
los s a n g le
luminance
luminous ffux
I u m in ou $ i nt en s it y
ma w
m a gn et ic con st a nt
m a gn et ic d ipole
moment
ma gn et ic flux
ma gnet ic flux densit y
m a gn et ic in d~ c tion
m agn et ic m om en t
m a gn et ic pola r iz a tion
m agn et ic pot en ia l d iffer
e n c e
m a gn et ic s us cept ibilit y y
ma gnet ic vect or pot en-
t ia l
momen t of a couple
[TE I . i N U S K B E R
NAME
:QU&DI~ ES)
momentum
n um ber of pa irs of poles
n umber of pha ses
n um ber of r evolu tion s
per t ime
winding
period
permit tivit v of va cuum
p ha s e coe ff ici en t
p ha s e d if kx -e nce
p ha s e d is pl a ce men t
pla n ck con st a nt
pla ne a ngle
pot en t ia l d if fer en ce
power
P oynt in g vect or
pressure
pr es su re (t em per a t ur e)
coeffici~ nt
pr opa g a t i on coef ficien t
q ua lit y fa ct or
q ua n t ]t y of elect r icit y
q ua nt it y of hea t
q ua nt it y of light
r a dia l d is ta n ce
radiance
r adia nt en er gy
I TE M N U M B E R
XN TAB LE S 1
(Qr:;:p)
r a dia n t in t en sit y
ra dia nt pow er
radius
reactance
r ea ct ive pow er
r ela t i ve per m ea b ili t y
r ela t i ve per m it t iv it y
reluctance
resist ivity
r ot a t ion a l fr eq u en cy
s el f i rs d uct a n ce
slip
speed ( linea r )
of
electromagnetic
waves
of
speed of rot a tion
st anda rd a ccelera t ion of
free fa li
108
109
108
7
94
100
81
63
91
87
88
i7
76
18
5;
23
201
2:;
11
NAME
wrface
charge
lusceptance
:e.mperature
~ em P e r a t u r e coe ff ici en t
tension
t h er m a l con d uct iv it y
t her mod yn a mic t em per -
a t u r e
thickness
t ime of on e cycle
torque
velocity
of
electromagnetic
waves
voltage
volume
charge
wavelength
weight
w i d t h
work
xx T~ B LE 1
 QUANTITIES)
hBSCEIPZ
0608
0706
0625
0318
I
0213
I
0516
0417,0606
SUBSCRIPT i
0502, 0518, 0605,0619
0612
0503
0705
0107,0601