Answer / gargee

In case of oil filled cables, the channels or ducts are provided within or adjacent to the cores, through which oil under pressure is circulated.

1.1 Advantages
The various advantages of oil filled cables are,
1. The thickness of insulation required is less hence smaller in size and weight.
2. The thermal resistance is less hence current carrying capacity is more.
3. The possibility of voids is completely eliminated.
4. The allowable temperature range is more than solid type cables.
5. Reduced possibility of earth fault. This is because in case of any defect in lead sheath, oil leakage starts, which can be noticed before earth fault occurs.
6. Perfect impregnation is possible.
1.2 Disadvantages
The disadvantages of oil filled cables are,
1. The initial cost is very high.
2. The long length are not possible.
3. The oil leakage is serious problem hence automatic signalling equipment is necessary.
4. The laying of cable is difficult and must be done very carefully.
5. Maintenance of the cables is also complicated.

Answer / jason

use of oil filled cable are at HV 33kv 66kv 132kv 330kv in
australia 275kv uk and 440kv uk. The oil is in the cable as
it is a good dieletric it also fills the void between the
primary insulation which is paper its also very good at
absorbing gases that are produced at very high voltages.
the life of the cable is very long and this can be
monitored by testing the oil looking for specfic gases that
indicated what is happening in the cable. The oil is
biodegradable its code is T3788 if you want to search this.
Disadvantages is maintenance and xlpe cable production is
improving all the time which is decreasing its losses in
its dielectric.or insulation.

Answer / jim

Oil filled cables are used, as back in the 1960's they were
the most cost effective method of implementing HV cables. It
wasnt until recent developments in XLPE cable that it became
a viable option instead of FFC. Fluid Filled cables are
mainly used as underground EHV ,extra high voltage,
typically 132kV in the uk.

the down side to these cables is that if they leak they can
cost a huge amount to repair. for a 30metre replacement of
FFC and 2 joints costs approx £100,000 GbP. also this type
of replacement could take up to 10 weeks to complete, with
excavations and leak detection.

to replace 15km of FFC with XLPE has been costed at
30million GBP.

FFC's are also often used in sub marine cables.

Answer / dayal varma

COOLING IS THE MAIN ADVANTAGE TO MAINTAIN TEMPERATURE IN
THE CABLE. LEAKE AND MAINTENANCE COST IS MORE.

Answer / jason008

oil filled cables are not like transformers as there are no
cooling towers for the oil to be circulated around
adv of oil or fluid filled cable. 1 Longer service life you
can mointor what is happening inside the cable you know if
a 3rd party has slightly hit the cable as you a low
pressure alarm goes off less dielectic losses smaller
conductor size for same ammount of current for xlpe see ppl
oil filled cable they have been used for many years
disav higher cost takes longer to join lead sheath of older
cables leak.. this has been improved by alum sheath
Xlpe adv cheaper less maintenance.
xlpe disadantages unable to see when the cable is going to
fail no pre warning water can migrate into xlpe greater
losses in xlpe you can not test the xlpe in the same manner
as oil cable satuation test which test stress cones ect its
the earlier joint where very hard to do.there are to many
variation of joints between diffrent companies

Answer / shahin

Adv
1. Increases the insulation between cable & earth.
2. Cable Cooling

Dis

1. Too much expensive
2. Meintenance is tough

Answer / thamizh

1.TO REDUCE THE TEMPERATURE
2. TO WITHSTAND THE CURRENT


DIS

OIL LEAK
MAITANANCE

DIFFICULT INSTALLATIOMN

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