In a HT cable there are 2 layers of semiconductor one on the conductor and second on the XLPE insulation.
As we know semiconductor behaves as conductor when temperature rises. So when the HT cable is on load its conductor temperature rises due to this the semicon layer which is on conductor behaves like conductor and as a result overall cross section area is increased.
now the second semicon layer which is over XLPE on temp rise behaves as conductor and used for dessipating heat out of conductor as the cable heat due to load.
For LT cable 1. Use : Up to 690V 2. Insulation : PVC 3. Core(Neutral) : Yes 4. Insulation Grading : 1100 V For HT cable 1. Use : Above 690 2. Insulation : XLPE 3. Core(Neutral) : No 4. Insulation Grading : Above 3.3kV, 11KV..etc ( Please note that now 690 V using in VFD application with LV cable and 440 V for DOT motor starter) from Kunal Singh Dabi the_dabi@rediffmaill.com
Frist putt of the main incomer HT side then Rack out the breaker and put the LOTO after that Discharge the cable Both side (HT/LT).
Dielectric Strength of Vacuum is more than that of Air. In HT voltage is more than LT. So VCB is used in HT & ACB in LT. Rakesh Gaikwad
because when ever fault current occurs then the cable wont get damaged due to cable armored earthing to the gland for fault current to pass through groung
to reduce Current and Coast
15 D
Cable glands are typically not used for high-tension (HT) cables because HT cables require specialized termination methods to manage the high voltages and prevent electrical arcing. HT cables often use insulated connectors and terminations that provide better sealing and insulation properties than standard cable glands. Additionally, the mechanical stresses and environmental factors associated with HT applications necessitate robust solutions that adhere to specific safety standards, which standard cable glands may not meet.
For LT cable 1. Use : Up to 690V 2. Insulation : PVC 3. Core(Neutral) : Yes 4. Insulation Grading : 1100 V For HT cable 1. Use : Above 690 2. Insulation : XLPE 3. Core(Neutral) : No 4. Insulation Grading : Above 3.3kV, 11KV..etc ( Please note that now 690 V using in VFD application with LV cable and 440 V for DOT motor starter) from Kunal Singh Dabi the_dabi@rediffmaill.com
Frist putt of the main incomer HT side then Rack out the breaker and put the LOTO after that Discharge the cable Both side (HT/LT).
Dielectric Strength of Vacuum is more than that of Air. In HT voltage is more than LT. So VCB is used in HT & ACB in LT. Rakesh Gaikwad
because when ever fault current occurs then the cable wont get damaged due to cable armored earthing to the gland for fault current to pass through groung
65 meg ohm if it is 11 kv
to reduce Current and Coast
1 look at them in the dark when power is running through them if you see a blue or orange arch your cable is faulty or use a mega ohm meter wrap the outer cable in foil ground it then mega it
Voltage transformer or potential Transformers are used in conjunction with Current transformers for metering and protection purpose in HT and LT power system.
what HT Swichgear
Swing your arms in circles for momentum. You would not do that if u were using ht hang technique.