What are the construction features of pole mounted substation?
Pole-Mounted substations are earthed at two or more places. The transformers having a capacity up to 125 KVA are mounted on the double pole structure and for the transformer having a capacity between 125 to 250 KVA 4-pole structure with the suitable platform is used.
Which type of earthing is found in 11kV substation?
Pipe earthing is the most common type used for residential quarters and strip earthing is used for 11 kV substation.
What earthing is in 11kV substation?
To achieve an EPR less than 430 volts at an overhead fed 11kV distribution substation, then the overall earth value would typically need to be less than 0.3 – 0.5 ohms.
What is GI earthing?
In areas with high soil resistivity, GI (Galvanized Iron) Earthing Electrodes give a low-impedance ground. The method dissipates lightning energy and other dangerous electrical fault currents, even in sandy or rocky soil conditions, when used in conjunction with Reflow Grounding Minerals.
What is the good earthing value?
Ideally a ground should be of zero ohms resistance. There is not one standard ground resistance threshold that is recognized by all agencies. However, the NFPA and IEEE have recommended a ground resistance value of 5.0 ohms or less.
What is the height of HT Pole?
Rectangular PCC Electric Pole, Height: 8.5 m
|Cement, Concrete and Iron Saria
|Use for Electric Wires
What is GI pole?
Galvanized Iron Poles are widely used for street lighting purposes and incredibly suitable for car parking, railway yard, road junction, factory premises etc. GI lighting poles are manufactured using high-quality steel, by bending, forming, welding, galvanization and powder coating techniques.
What is the length of the GI pipe in the pipe earthing?
For Pipe type earthing normal practice is to use GI pipe [C-class] of 75 mm diameter, 10 feet long welded with 75 mm diameter GI flange having 6 numbers of holes for the connection of earth wires and inserted in ground by auger method.
What is the depth of earth pit?
Earthing pits should be big and deep (at least 1.5 × 1.5 × 3.0 m3.) and electrodes should be buried deep (at least 4 ft) to reduce earthing resistance, and earthing conductor termination to earth electrode should be done well. As the ground rod is driven deeper into the earth, its resistance is significantly reduced.
What type of earthing is found in 11kv substation?
Why GI pipe is used in earthing?
G.I. Pipe Earthing: For earthing house wiring, factory wiring (specially electrical installations of big factories), neutral wire of the supply line etc., galvanized iron pipe is generally used as earth electrode. The size of the pipe depends upon fault current and the condition of the soil.
What is a pole mounted substation?
Pole Mounted Substation: The pole mounted substations are majorly distribution substations which are constructed on the structure of two, four, or sometimes six or more poles. In such substations, there is a need of mounting distribution transformers over poles alongside isolator switches.
How to design and build a substation?
Create the substation project with scheduled milestones and in-service date. Assign the project team resources with in-house staff, external staff/contractors, or contract entire project as a turnkey solution, engineer-procure-construct (EPC) option, etc. Begin engineering & design of substation drawing package and deliverables.
What are high-voltage substations?
These voltages are for consumers to use for their actual loads. These substations are having high-voltage bearable wires and conductors having one neutral to ground and 4 live wires.
What is a step-up substation?
The step-up substation may have circuit breakers which are utilized for transmission and generation circuits in the case when required to be shut down. The specified voltages which are leaving the step-up transmission are to be analyzed through customer’s needs.