Thanks for taking a look Jim. How would you go about performing the calculation? As the phase conductors are shielded and in contact with the ground conductors they should be at or very near ground potential. I am trying to understand what the capacitive coupling is that you are talking...
Jim,
Regarding your comment about capacitive coupling. You think so? The phase conductors are all shielded with a copper/nylon braid shield on top of a semi-con bedding tape on top of an extruded insulation shield. that braid is in contact with the ground wires so that's all at ground...
Jim,
Thank you for pointing out the units. I hate them also and keep pushing that we use the more correct kft. abbreviation as its really per 1000 ft. Apparently "MFT." is an old industry abbreviation and switching to something that makes sense just caused problems for customers...
I don't...
Wow!
Thank you ALL for your responses. I never expected to find such support here. I am impressed. I will try to address your very good questions and comments below:
1) Annorlunda:
The cable has 3 shielded power conductors, 2 bare ground conductors, and one insulated ground check...
Say I have two parallel conductors that are both L long and d distance apart (center to center). I run AC power of frequency f and RMS voltage V through one conductor. That current will create a fluctuating magnetic field which will pass through the the other conductor and generate a voltage...
OK, I have the dimensions.
500 kcmil fine stranded Conductor OD: 0.736 inches
Diameter over Insulation and shield: 1.45 inches
Current on each phase conductor: 590A , voltage 25kV (we don't need voltage right, just current)
Diameter over Ground Conductor: 0.423 inches
Cable Length 3600 meters...
I did determine the relative distances. If R is the diameter over the large insulated conductor and r is the diameter over the insulated ground check and the ground wires (that not exact but usually close) than the center of each ground and ground check is R+r away from 2 phases and the...
Thank you. This specific case is for 3900m of 25kV rated cable. I will find out the actual operating voltage and conductor size. But I would like to know how to calculate this for various cabe sizes, voltage ratings and cable lengths. As I said, this will be a three conductor cable with...
That makes sense. I am wondering how to model this exactly. The reason I am asking is I am working with a mine that that is having a problem which I have seen come up before. The cable is a medium voltage cable with 3 copper braid shielded conductors and 2 ground wires in two interstices and...
Say I have two parallel conductors that are both L long and d distance apart (center to center). I run AC power of frequency f and RMS voltage V through one conductor. That current will create a fluctuating magnetic field which will pass through the the other conductor and generate a voltage...