42 feet galvanized structures are best for your requirements, using three disc insulators you can string the line.The errection is possible through tripot ,lifter or even through hands.
Dear Mazhar123,
How to determine whether transposition is required or not? If it is required then at what distance and what will be the total number of transposition in the span of 300 meters.
Regards,
Nihar
Mazhar,
I realized that what you gave was for a lower voltage. We normally use 5 or 6 disc insulators for 69 kV, and 42 feet is quite low for that voltage class. However, I was more concerned with the manner in which they are erected which I believe would be the similar. By the way, you mentioned the use of a lifter. By this, I suppose you were refering to a gin pole?
Please define "rural." It means one thing in Kansas, quite another in Utah.
Assuming your alignment is fairly flat:
If you reduce your pole spacing, you can use direct embed monopole structures instead of H-frames or lattice towers. This has a lot of advantages: faster erection with smaller equipment, reduced construction cost, simpler installation (particularly when compared to lattice towers).
300 meters = 984 feet
200 meters = 656 feet
If you reduce your spacing to about 200 meters, then direct embed monopoles are feasible.