69 kv Cable, Underground Installation

Where (on earth) are you located? This factor alone will have some bearing on any special requirements.

No, you will not find any "typical" installation drawings that will help you. My experience dictates that there are no 'typical" UG 69kv installations.

Special requirements:

Should be contained in the Project Specifications.

Should be available through your local AHJ (authority having jurisdiction).

Should be available through your local utility (if applicable).

UG MV/HV installations may required some or all of the following:

Specific cable specified for the particular project.

Minimum burial depth of 42"

Electrical Manhole(s) w/cover stamped "Electric" every XXX amount of feet

PVC or RGS conduit with long sweep elbows

Specific trench bedding i.e. sand, gravel, ect. before conduit/duct bank goes in.

Specific backfill and compaction requirements

Specific concrete strength

Concrete encased conduit systems or concrete duct banks

Red dyed concrete for encasement or duct bank

Magnetic tape over direct buried cable/duct bank

HV Megger testing of installed cables with computer generated pass/fail/duration/voltage test results

High Pot test if we furnish and install terminations (utilities in my area of work furnish and install their own terminations and do their own testing).

Detailed red line drawings to owner/utility/AHJ showing exact routing of MV line

This is a very short list of the requirements. The typical specification section of UG/HV/MV cable installations are usually 10 pages minimum.

Your questions indicate that this task may exceed your expertise. You may want to contact and hire a company that specializes in MV/HV work.

You don't will not get second chances with 69kv.

DO NOT ATTEMPT THIS YOURSELF. YOU MAY VERY WELL KILL SOMEONE, BESIDES YOURSELF.

As KJK/USA corrrectly pointed out, you aren't qualified to do this type of work. Hire an expert!