So before I buy your course, what about split factor? Is there a reason why you're assuming all the fault current returns via the earth grid at the substation? Thanks
sir can u explain by video what happen if we use different class for overhead line..substation A using CT class X..but another remote end substation using CT class 5P20..what happen if fault occured..??
Hi, The 5P20 CT’s will be less accurate than the class X CT’s, this will become clear if you have a high current fault and the relays at the two ends will show different current levels, this difference may in incorrectly identify a fault on the line being protected. Regards Steve
Hi Kevin, at several cable joints along the route we ground the sheath with a non linear resistor to keep the induced voltage down to an acceptable level. steve
Hi Nino, I would suggest looking at the free RU-vid videos to give you an introduction, if your interested do the full Udemy courses to give you in depth knowledge. Regards Steve
Hi Ryan, Use the voucher code TWHD1001 to get the following Udemy courses for $9.99…. ELECTRICAL CONTROL & PROTECTION SYSTEMS ELECTRICAL CONTROL & PROTECTION SYSTEMS PART 2 ELECTRICAL CONTROL & PROTECTION SYSTEMS PART 3 ELECTRICAL CONTROL & PROTECTION SYSTEMS PART 4 ELECTRICAL CONTROL & PROTECTION SYSTEMS PART 5 AIR INSULATED SUBSTATION DESIGN AIR INSULATED SUBSTATION DESIGN PART 2 AIR INSULATED SUBSTATION DESIGN PART 3 SUBSTATION GROUNDING ELECTRICAL POWER EQUIPMENT ELECTRICAL POWER ENGINEERING CONSTRUCTION SITE ELECTRICAL SYSTEM DESIGN COUPONS ONLY VALID UNTIL THE 3rd March 2024 Regards steve
I appreciate your walkthrough Stephen. I am studying for the PE (power) exam and this helped me tremendously. One thing I want to add is the formula you referenced is only applicable for grids with depths between 0.25 - 2.5m. However, the concepts remain the same and all formulas are provided by NCEES. Thank you again!
Thanks for the formula and explanation. Will the shape of the earth system conductor play a roll in the Value of Rg. A rectangular bar will have a larger circumference and more contact area with ground than a round conductor.
I wonder if it is an ANSI vs. IEC thing, but normally in ANSI we would have the CT's on the opposite side of the breakers, as shown. This was the breakers at each end are protected by the differential protection. In the scheme as shown, either breaker could fail and would need some other protection scheme to sense the fault.
Hi, it’s not really an ANSI/IEC conflict, most utilities only have one set of current transformers on the line side now to save money and use other protection functions to detect a fault in between the CT / circuit breaker ( short stub fault ). Steve
@@Electricalsteve Maybe it's a regional thing. I commission HV substations, including the apparatus outside and the protection systems inside the control house. Our standard new dead tank circuit breakers have a total of 18 CT's per breaker. For a line breaker the bus side CT's are used for primary and secondary line protection and the line side CT's are for primary / secondary bus protection. Having the diff CT's on line side ensures the breaker itself is covered in the diff scheme. In a ring or breaker and a half scheme, it may be a little different. One last set of CT's may be used for breaker failure protection and the last may be for revenue metering. We have older installations that don't have as many CT's (we call CT deficient), but that can cause issues down the line - shared CT circuits and someone does maintenance test with doble -plugs paddle in while connected to doble and shorts diff relay and a nuisance trip. I believe for the relative low cost of additional CT's on a dead tank, many utilities choose to have the extra CT's for flexibility and ease of wiring and maintenance. Digital relays also help quite a bit if sharing CT's as the polarity can be adjusted internally in the relay for compensate.
Man, you are good! Please understand that, you are legend. Just the way you start from the very bottom and cover everything up to the top is the only way I can understand.
Hi Muhammad , To use the attached coupon code go to the Udemy website, register, search for the course / my name ( Stephen Brooks ) then select the course you want and enter the $9.99 voucher code UHEK1001 Regards steve
Hi, The system voltage is kept constant regardless of the power output of the transformers or the size of the loads. If the voltage is constant then the only thing that can change as the power magnitude changes is the current and it does, when the power drawn by the load increases the current increases. Regards Steve
Hi Zaid Go to the Udemy website, search for courses under my name ( Stephen brooks ) & use the voucher code IGST1001 to get them for $9.99, vouchers expire in 5 days. Regards Stephen Brooks
Hi Daniel Go to the Udemy website, search for courses under my name ( Stephen brooks ) & use the voucher code IGST1001 to get them for $9.99, vouchers expire in 5 days. Regards Stephen Brooks
Sir, what about the electrical room in which main panel (floor mounted) of the building are installed. half meter distance is enough from the wall for future maintenacne?
Hi Osman, I recommend 1.5 meters in the video, but the actual distance will depend on your circumstances….as a minimum you need to be able to walk between the opened panel door and wall…Steve
