ELECTRIC SUPPLY LINES, SYSTEMS AND APPARATUS FOR HIGH AND EXTRA-HIGH
VOLTAGES
Rule-63: Approval by Inspector:
(1) Before making an application
to the Inspector for permission 1[to commence or recommence supply after an
installation has been disconnected for one year and above] at high or
extra-high voltage to any person, the supplier shall ensure that the high or
extra-high voltage electric supply lines or apparatus belonging to him are placed
in position, properly joined and duly completed and examined. The supply of
energy shall not be commenced by the supplier unless and until the Inspector is
satisfied that the provisions of rules 65 to 69 both inclusive have been
complied with and the approval in writing of the Inspector have been obtained
by him.
Provided that the supplier may
exercise the aforesaid electric supply lines or apparatus for the purpose of
tests specified in rule 65.
(2) The owner of any high or
extra-high voltage installation shall, before making application to the
Inspector for approval of his installation or additions thereto, test every
high or ext.-a-high voltage circuit or additions thereto, other than an
overhead line, and satisfy himself that they withstand the application of the
testing voltage set out in sub-rule (1) of rule 65 and shall duly record the
results of such tests and forward them to the Inspector.
Provided that an Inspector may
direct such owner to carry out such tests as he deems necessary or, if he thinks
fit, accept the manufacturer’s certified tests in respect of any particular
apparatus in place of the tests required by this sub-rule.
(3) The owner of any high or
extra-high voltage installation who makes any additions or alterations to his
installation shall not connect to the supply his apparatus or electric supply
lines, comprising the said alterations or additions unless and until such
alterations or additions have been approved in writing by the Inspector.
Rule-64: Use of energy at high and extra-high voltage:
(1) 2[The Inspector shall not
authorise the supplier to commence supply or where the supply has been
discontinued for a period of one year and above, to commence the supply at high
or extra-high voltage to any consumer unless,]
(a) All conductors
and apparatus situated on the premises of the consumer are so placed as to be
inaccessible except to an authorised person and all operations in connection
with the said conductors and apparatus are carried out by an authorised person;
(b) The
consumer has provided and agrees to maintain a separate building or a locked
weather-proof and fire-proof enclosure of agreed design and location, to which
the supplier at all times have access for the purpose of housing his apparatus
and metering equipment, or where the provision for a separate building or
enclosure is impracticable, the consumer has segregated the aforesaid apparatus
of the supplier from any other part of his own apparatus;
Provided that
such segregation shall be by the provision of fire proof walls, if the
Inspector considers it to be necessary;
Provided
further that in the case of an out-door installation consumer shall suitably
segregate the aforesaid apparatus belonging to the supplier from his own to the
satisfaction of the Inspector;
(c) All pole
type sub-stations are constructed and maintained in accordance with rule 69.
(2) The following provisions
shall be observed where energy at high or extra high voltage is supplied,
converted, transformed or used:
(a)
3[(i)
Clearances as per Indian Standard Code shall be provided for electrical
apparatus so that sufficient space is available for easy operation and
maintenance without any hazard to the operating and maintenance personnel
working near the equipment and for ensuring adequate ventilation.
(ii) The
following minimum clearances shall be maintained for bare conductors or live
parts of any apparatus in out-door substations, excluding overhead lines, of HV
and EHV installations:
|
System Voltage (kV)
|
Ground Clearance (Meters)
|
Sectional Clearance (Meters)
|
|
11
|
2.75
|
2.6
|
|
33
|
3.7
|
2.8
|
|
66
|
4.0
|
3.0
|
|
132
|
4.6
|
3.5
|
|
220
|
5.5
|
4.3
|
|
400
|
8.0
|
6.5
|
(b) The
windings of motors or other apparatus within reach from any position in which a
person may require to be shall be suitably protected so as to prevent danger.
(c) Where
transformer or transformers are used, suitable provision shall be made, either
by connecting with earth a point of the circuit at the lower voltage or
otherwise, to guard against danger by reason of the said circuit becoming
accidentally charged above its normal voltage by leakage from or contact with
the circuit at the higher voltage.
(d) A
sub-station or a switch station with apparatus having more than 2000 litres of
oil shall not 4[*** **] be located in the basement where
proper oil draining arrangement cannot be provided.
(e) Where a
sub-station or a switch station with apparatus having more than 2000 litres of
oil is installed, whether indoor or out-doors, the following measures shall be
taken, namely:
(i) The baffle
walls 5[of
4 hour fire rating] shall be provided between the apparatus in the following
cases:
(A) Single
phase banks in the switch-yards of generating stations and substations;
(B) On the
consumer premises;
(C) Where
adequate clearance between the units is not available.
(ii)
Provisions shall be made for suitable oil soak pit and where use of more than
9000 litres of oil in any one oil tank, receptacle or chamber is involved,
provision shall be made for the draining away or removal of any oil which may
leak or escape from the tanks receptacles or chambers containing the same,
special precautions shall be taken to prevent the spread of any fire resulting
from the ignition of the oil from any cause and adequate provision shall be
made for extinguishing any fire which may occur. Spare oil shall not be stored
in any such sub-station or switch station.
(f)
(i) 6[Without
prejudice to the above measures, adequate fire protection arrangement shall be
provided for quenching the fire in the apparatus;
(ii) Where it
is necessary to locate the sub-station/switch station in the basement following
measures shall be taken:
(a) The room
shall necessarily be in the first basement at the periphery of the basement;
(b) The
entrances to the room shall be provided with fire resisting doors of 2 hours
fire rating. A curb (sill) of a suitable height shall be provided at the
entrance in order to prevent the flow of oil from a ruptured transformer into
other parts of the basement. Direct access to the transformer room shall be
provided from outside.
(c) The
transformer shall be protected by an automatic high velocity water spray system
or by carbon dioxide or BCF (Bromochlorodifluoromethane) or BTM (Bromotrifluoromethane)
fixed installation system; and
(iii) Oil
filled transformers installed indoors shall not be on any floor above the
ground or below the first basement.]
(g) Cable
trenches inside the sub-stations and switch stations containing cables shall be
filled with sand, pebbles or similar non-inflammable materials or completely
cover with non-inflammable slabs.
(h) Unless the
conditions are such that all the conductors and apparatus may be made dead at
the same time for the purpose of cleaning or for other work, the said
conductors and apparatus shall be so arranged that these may be made dead in
sections, and that work on any such section may be carried on by an authorised
person without danger.
(i) Only
persons authorised under sub-rule (1) of rule 3, shall carry out the work on
live lines and apparatus.]
(3) 7[All EHV apparatus shall
be protected against lightning as well as against switching over voltages. The
equipment used for protection and switching shall be adequately coordinated
with the protected apparatus to ensure safe operation as well as to maintain
the stability of the inter-connected units of the power system.]
Rule-64A: 8[Additional provisions for use of
energy at high and extra-high voltage:
The following additional
provisions shall be observed where energy at high or extra high voltage is
supplied, converted, transferred or used, namely:
(1) Inter-locks- Suitable
inter-locks shall be provided in the following cases:
(a) Isolators
and the controlling circuit breakers shall be interlocked so that the isolators
cannot be operated unless the corresponding breaker is in open position;
(b) Isolators
and the corresponding earthing switches shall be interlocked so that no
earthing switch can be closed unless and until the corresponding isolator is in
open position;
(c) Where two
or more supplies are not intended to be operated in parallel, the respective
circuit breakers or linked switches controlling the supplies shall be
interlocked to prevent possibility of any inadvertent paralleling or feedback;
(d) When two
or more transformers are operated in parallel, the system shall be so arranged
as to trip the secondary breaker of a transformer in case the primary breaker
of that transformer trips;
(e) All gates
or doors which give access to live parts of an installation shall be
inter-locked in such a way that these cannot be opened unless the live parts are
made dead. Proper discharging and earthing of these parts should be ensured
before any person comes in close proximity of such parts;
(f) Where two
or more generators operate in parallel and neutral switching is adopted,
inter-lock shall be provided to ensure that generator breaker cannot be closed
unless one of the neutrals is connected to the earthing system.
(2) Protection- All systems and
circuits shall be so protected as to automatically disconnect the supply under
abnormal conditions. The following protection shall be provided, namely:
(a) Over
current protection to disconnect the supply automatically if the rated current
of the equipment, cable or supply line is exceeded for a time which the
equipment, cable or supply line is not designed to withstand;
(b)
Earth-fault/earth leakage protection to disconnect the supply automatically if
the earth fault current exceeds the limit of current for keeping the contact
potential within the reasonable values;
(c) Gas
pressure type protection to given alarm and tripping shall be provided on all
transformers of ratings 1000 KVA and above;
(d)
Transformers of capacity 10 MVA and above shall be protected against incipient
faults by differential protection; and
(e) All
generators with rating of 100 KVA and above shall be protected against earth
fault/leakage. All generators of rating 1000KVA and above shall be protected
against faults within the generator winding using restricted earth fault
protection or differential protection or by both.]
Rule-65: Testing, Operation and Maintenance:
(1) Before approval is accorded
by the Inspector under rule 63, the manufacturer’s test certificates shall, if
required, be produced for all the routine tests as required under the relevant
Indian Standard.
(2) No new HV or EHV apparatus,
cable or supply line shall be commissioned unless such apparatus, cable or
supply line are subjected to site tests as per relevant code of practice of the
9[Bureau
of Indian Standards].
(3) No HV of EHV apparatus, cable
or supply line which has been kept disconnected, for a period of 6 months or
more, from the system for alterations or repair shall be corrected to the
system until such apparatus, cable or supply line are subjected to the relevant
tests as per code of practice of 9[Bureau of Indian Standards.]
(4) Notwithstanding the
provisions of sub-rules (1) to (3) (both inclusive) the Inspector may require
certain additional tests to be carried out before charging the installations or
subsequently.
(5) All apparatus, cables and
supply lines shall be maintained in healthy conditions and tests shall be
carried out periodically as per the relevant codes of practice of the 9[Bureau
of Indian Standards].
(6) Records of all tests,
trappings, maintenance works and repairs of all equipment, cables and supply
lines shall be duly kept in such a way that these records can be compared with
earlier ones.
(7) It shall be the
responsibility of the owner of all HV and EHV installations to maintain and
operate the installations in a condition free from danger and as recommended by
the manufacturer and/or by the relevant codes of practice of the 9[Bureau
of Indian Standards] and/or by the Inspector.]
Rule-66: Metal sheathed electric supply lines. Precautions against
excess leakage:
(1) The following provisions
shall apply to electric supply lines (other than overhead lines 10[***
* *] for use at high or extra-high voltage:
(a) The
conductors shall be enclosed in metal sheathing which shall be electrically
continuous and connected with earth, and the conductivity of the metal
sheathing shall be maintained and reasonable precautions taken where necessary
to avoid corrosion of the sheathing;
Provided that
in the case of thermoplastic insulated and sheathed cables with metallic armour
the metallic wire or tape armour shall be considered as metal sheathing for the
purpose of this rule;
Provided
further that this rule shall not apply to cable with thermoplastic insulation
without any metallic screen or armour.
(b) 11[The
resistance of the earth connection with metallic sheath shall be kept low
enough to permit the controlling circuit breaker or cut-out to operate in the
event of any failure of insulation between the metallic sheath and the
conductor.]
(c) Where an
electric supply-line as aforesaid has concentric cables and the external
conductor is insulated from an outer metal sheathing and connected with earth,
the external conductor may be regarded as the metal sheathing for the purposes
of this rule provided that the foregoing provisions as to conductivity are
complied with.
(2) Nothing in the provisions of
sub-rule (1) shall preclude the employment in generating stations, sub-stations
and switch-stations (including outdoor substations and outdoor switch-stations)
of conductors for use at high or extra high voltages which are not enclosed in
metal sheathing or preclude the use of electric supply lines laid before the
prescribed date to which the provisions of these rules apply
Rule-67: Connection with earth:
(1) 11[All non-current
carrying metal parts associated with HV/EHV installation shall be effectively
earthed to a grounding system or mat which will:
(a) Limit the
touch and step potential to tolerable values;
(b) Limit the
ground potential rise to tolerable values so as to prevent danger due to
transfer of potential through ground, earth wires, cables sheath fences, pipe
lines, etc.;
(c) Maintain
the resistance of the earth connection to such a value as to make operation of
the protective device effective.
(lA) In the case of star-connected system with
earthed neutrals or delta connected system with earthed artificial neutral
point:
(a) The
neutral point of every generator and transformer shall be earthed by connecting
it to the earthing system as defined in rule 61(4) and hereinabove by not less
than two separate and distinct connections;
Provided that
the neutral point of a generator may be connected to the earthing system through
an impedance to limit the fault current to the earth;
Provided
further that in the case of multi-machine system neutral switching may be
resorted to, for limiting the injurious effect of harmonic current circulation
in the system;
(b) In the
event of an appreciable harmonic current flowing in the neutral connection so
as to cause interference, with communication circuits, the generator or
transformer neutral, shall be earthed through a suitable impedance;
(c) In case of
the delta connected system the neutral point shall be obtained by the insertion
of a grounding transformer and current limiting resistance or impedance
wherever considered necessary at the commencement of such a system.]
(2) Single-phase high or
extra-high voltage systems shall be earthed in a manner approved by the
Inspector.
(3) In the case of a system
comprising electric supply lines having concentric cables, the external
conductor shall be the one to be connected with earth.
(4) Where a supplier proposes to connect
with earth an existing system for use at high or extra-high voltage which has
not hitherto been so connected with earth he shall give not less than fourteen
days’ notice in writing together with particulars to the telegraph-authority of
the proposed connection with earth.
(5)
(a) Where the
earthing lead and earth connection are used only in connection with earthing
guards erected under high or extra-high voltage overhead lines where they cross
a telecommunication line or a railway line, and where such lines are equipped
with earth leakage relays of a type and setting approved by the Inspector, the
resistance shall not exceed 25 ohms.
(b) Every
earthing system belonging to either the supplier or the consumer shall be
tested for its resistance to earth on a dry day during dry season not less than
once a year. Records of such tests shall be maintained and shall be produced,
if required before the Inspector or any officer appointed to assist him and
authorised under sub-rule (2) of rule 4A.
(6) In so far as the provisions
of rule 61 are consistent with the provisions of this rule, all connections
with earth shall also comply with the provisions of that rule.
Rule-68: General conditions as to transformation and control of energy:
(1) Where energy at high or
extra-high voltage is transformed, converted, regulated or otherwise controlled
in sub-stations or switch-stations (including outdoor substations and out-door
switch-stations) or in street boxes constructed underground, the following
provisions shall have effect:
(a) 13[Sub-stations
and switch-stations shall preferably be erected above ground, but where
necessarily constructed underground due provisions for ventilation and drainage
shall be made and any space housing switchgear shall not be used for storage of
any materials especially inflammable and combustible materials or refuse.]
(b) Outdoor
sub-station is except pole type sub-stations and. outdoor switch stations shall
(unless the apparatus is completely enclosed in a metal covering connected with
earth, the said apparatus also being connected with the system by armoured
cables) be efficiently protected by fencing not less than 1.8 metres in height
or other means so as to prevent access to the electric-supply lines and
apparatus therein by an unauthorised person.
(c) Underground
street boxes (other than sub-stations) which contain transformers shall not
contain switches or other apparatus, and switches, cut-outs or other apparatus
required for controlling or other purposes shall be fixed in separate
receptacles above ground wherever practicable.
(2) Where energy is transformed,
suitable provisions shall be made either by connecting with earth a point of
the system at the lower voltage or otherwise to guard against danger by reason
of the said system becoming accidentally charged above its normal voltage by
leakage from a contact with the system at the higher voltage.
Rule-69: Pole type sub-stations:
Where platform type construction
is used for a pole type sub-station and sufficient space for a person to stand
on the platform is provided a substantial hand rail shall be built around the
said platform and if the hand rail is of metal, it shall be connected with
earth;
Provided that in the case of pole
type sub-station on wooden supports and wooden platform the metal hand-rail
shall not be connected with earth.
Rule-70: Condensers:
Suitable provision shall be made
for immediate and automatic discharge of every static condenser on
disconnection of supply.
Rule-71: Additional provisions for supply to high voltage luminous tube
sign installation
(1) Any person who proposes to
use or who is using energy for the purpose of operating a luminous tube sign
installation, or who proposes to transform or who is transforming energy to a
high voltage for any such purpose shall comply with the following conditions:
(a) All live
parts of the installation (including all apparatus and live conductors in the
secondary circuit, but excluding tubes except in the neighbourhood of their
terminals) shall be inaccessible to unauthorised persons and such parts shall
be effectively screened.
(b)
Irrespective of the method of obtaining the voltage of the circuit which feeds
the luminous discharge tube sign, no part of any conductor of such circuit
shall be in metallic connection (except in respect of its connection with
earth) with any conductor of the supply system or with the primary winding of
the transformer.
(c) All live
parts of an exterior installation shall be so disposed as to protect them
against the effects of the weather and such installation shall be so arranged
and separated from the surroundings as to limit, as far as possible, the
spreading of fire.
(d) The
secondary circuit shall be permanently earthed at the transformer and the core
of every transformer shall be earthed.
(e) Where the
conductors of the primary circuit are not in metallic connection with the
supply conductors, (e.g., where a motor-generator or a double-wound convertor
is used), one phase of such primary circuit shall be permanently earthed at the
motor generator or convertor, or at the transformer.
(ee) 14[An
earth leakage circuit breaker of sufficient rating shall be provided on the low
voltage side to detect the leakage in such luminous tube sign installations.]
(f) A final
sub-circuit which forms the primary circuit of a fixed luminous discharge tube
sign installation shall be reserved solely for such purpose.
(g) A separate
primary final sub-circuit shall be provided for each transformer or each group
of transformers having an aggregate input not exceeding 1,000 volt amperes, of
a fixed luminous-discharge tube sign installation.
(h) An
interior installation shall be provided with suitable adjacent means for
disconnecting all phases of the supply except the “neutral” in a three-phase
four wire circuit.
(i) For
installations on the exterior of a building a suitable emergency fire-proof
linked switch to operate on all phases except the neutral in a three phase four
wire circuits shall be provided and fixed in a conspicuous position at not more
than 2.75 metres above the ground.
(j) A special
“caution” notice shall be affixed in a conspicuous place on the door of every
high voltage enclosure to the effect that the low voltage supply must be cut
off before the enclosure is opened.
(k) Where static
condensers are used, they shall be installed on the load side of the fuses and
the primary (low voltage) side of the transformers.
(l) Where
static condensers are used on primary side, means shall be provided for
automatically discharging the condensers when the supply is cut off;
Provided that
static condensers or any circuit interrupting devices on the high or extra-high
voltage side shall not be used without the approval in writing of the
Inspector.
(2) The owner or user of any
luminous tube sign or similar high voltage installation shall not bring the
same into use without giving to the Inspector not less than 14 day’s notice in
writing of the intention so to do.
Rule-72: Additional provisions for supply to high voltage electrode boilers:
(1) Where a system having a point
connected with earth is used for supply of energy at high or extra-high voltage
to an electrode boiler which is also connected with earth, the following
conditions shall apply:
(a) The metal
work of the electrode boiler shall be efficiently connected to the metal
sheathing and metallic armouring (if any) of the high voltage electric supply
line whereby energy is supplied to the electrode boiler.
(b) The supply
of energy at high or extra-high voltage to the electrode boiler shall be
controlled by a suitable circuit-breaker so set as to operate in the event of
the phase currents becoming unbalanced to the extent of 10 per cent of the
rated current consumption of the electrode boiler under normal conditions of
operation;
Provided that
if in any case a higher setting is essential to ensure stability of operation
of the electrode boiler, the setting may be increased so as not to exceed 15
per cent of the rated current consumption of the electrode boiler under normal
conditions of operation.
(c) An inverse
time element device may be used in conjunction with the aforesaid circuit
breaker to prevent the operation thereof unnecessarily on the occurrence of
unbalanced phase currents of momentary or short duration.
(d) The
supplier shall serve a notice in writing on the telegraph-authority at least
seven days prior to the date on which such supply of energy is to be afforded
specifying the location of every point (including the earth connection of the
electrode boiler) at which the system is connected with earth.
(2) The owner or user of any high
or extra-high voltage electrode boiler shall not bring the same into use
without giving the Inspector not less than 14 days’ notice in writing of his
intention so to do.
Rule-73: Supply to X-ray and high frequency installation:
(1) Any person who proposes to
employ or who is employing energy for the purpose of operating an X-ray or
similar high-frequency installation shall comply with the following conditions:
(a) Mechanical barriers shall be
provided to prevent too close an approach to any high-voltage parts of the
X-ray apparatus, except the X-ray tube and its leads, unless such high-voltage
parts have been rendered shock-proof by being shielded by earthed metal or
adequate insulating material.
(b) Where extra-high voltage
generators operating at 300 peaks KV or more are used, such generators shall be
installed in rooms separate from those containing the other equipment and any
step-up transformer employed shall be so installed and protected as to prevent
danger.
(c) A suitable switch shall be
provided to control the circuit supplying a generator, and shall be so arranged
as to be open except while the door of the room housing the generator is locked
from the outside.
(d) X-ray tubes used in therapy
shall be mounted in an earthed metal enclosure.
(e) Every X-ray machine shall be
provided with a millimetre or other suitable measuring instrument, readily
visible from the control position and connected, if practicable, in the earthed
lead, but guarded if connected in the high-voltage lead.
(ee) 15[Notwithstanding the
provisions of clause (e), earth. leakage circuit breaker of sufficient rating
shall be provided on the low voltage side to detect the leakage in such X-ray
installations.]
(f) This sub-rule shall not apply
to shock-proof portable units or shockproof self-contained and stationary
units.
Note: The
expression “shock-proof”, as applied to X-ray and high-frequency equipment,
shall mean that such equipment is guarded with earthed metal so that no person
may come into contact with any live part.
(2)
(a) In the
case of non-shock-proof equipment, overhead high-voltage conductors, unless
suitably guarded against personal contact, shall be adequately spaced and
high-voltage leads on tilting tables and fluoroscopes shall be adequately
insulated or so surrounded by barriers as to prevent inadvertent contact.
(b) The low
voltage circuit of the step up transformer shall contain a manually operated
control device having overload protection, in addition to the over-current
device for circuit protection, and these devices shall have no exposed live
parts and for diagnostic work there shall be an additional switch in the said
circuit, which shall be of one of the following types:
(i) A switch
with a spring or other mechanism that will open automatically except while held
close by the operator, or
(ii) A time
switch which will open automatically after a definite period of time for which
it has been set
(c) If more
than one piece of apparatus be operated from the same high or extra high
voltage source each shall be provided with a high or extra high voltage switch
to give independent control.
(d) Low
frequency current-carrying parts of a machine of the quenched gap or open gap
type shall be so insulated or guarded that they cannot be touched during
operation, the high frequency circuit proper which delivers high-frequency
current normally for the therapeutic purposes, being exempted.
(e) All X-ray
generators having capacitors shall have suitable means for discharging the
capacitors manually.
(f) Except in
the case of self-contained units, all 200 peaks KV or higher, X-ray generators
shall have a sphere gap installed in the high-voltage system adjusted so that
it will break down on over-voltage surges.
(3)
(a) All
non-current carrying metal parts of tube stands, fluoroscopes and other
apparatus shall be properly earthed and insulating floors, mats or platforms
shall be provided for operator in proximity to high or extra-high voltage parts
unless such parts have been rendered shock proof.
(b) Where
short wave therapy machines are used, the treatment tables and examining chairs
shall be wholly non-metallic.
(4) The owner of any X-ray
installations or similar high frequency apparatus shall not bring the same into
use without giving to the Inspector not less than 14 days’ notice in writing of
his intention to do so.
Provided that the aforesaid
notice shall not be necessary in the case of shockproof portable X-ray and
high-frequency equipment which have been inspected before the commencement of
their use and periodically, thereafter.
1. Subs. by GSR 256, Date. 28.2.1983, with effect
from: 26.3.1983.
2. Subs. by CSR 843, Date. 23.7.1983, with effect
from: 7.9.1985
3. Subs. by
GSR 358, Date. 30.4.1987, with effect from: 9.5.1987.
4. The word
‘ordinarily’ omitted by GSR 358, Date. 30.4.1987, with effect from: 9.5.1987.
5. Ins. by GSR 358, Date. 30.4.1987, with effect
from: 9.5.1987.
6. Subs. by GSR 358, Date. 30.4.1987, with effect
from: 9.5.1987.
7. Ins. by GSR 336, Date. 20.3.1988, with effect
from: 23.4.1988.
8. Ins. by GSR 358, Date. 30.4.1987, with effect
from: 9.5.1987.
9. Subs. by
GSR 466, Date. 18.7.1991, with effect from: 17.8.1991.
10. The
words “of a supplier” omitted by GSR 358, Date. 30.4.1987, with effect from:
9.5.1987.
11. Subs. by GSR 466, Date. 18.7.1991, with effect
from: 17.8.1991.
12. Subs. by GSR 358, Date. 30.4.1987, with effect
from: 9.5.1987.
13. Subs. by GSR 358, Date. 30.4.1987, with effect
from: 9.5.1987.
14. Ins. by GSR 844, Date. 31.7.1985, with effect
from: 7.9.1985.
15. Ins. by GSR 844, Date. 31.7.1985, with effect
from: 7.9.1985.
