I recently drilled through the floor to run a CAT6 cable and hit the main feed to our panel. I'm in a duplex with a meter main panel with 2 meters and 2 100A breakers, one for each unit. The cable that runs from the meter main to the sub-panel in my unit got damaged. Basically a big arc and flash as I bridged the hot and neutral, the tip of the drill bit was vaporized.
It did not trip the main 100A breaker. I temporarily fixed it by opening up the cavity between the ceiling and the floor, and insulating the damaged conductors after I removed the sheathing. I estimate that maybe 20% of the conductor is locally removed when I hit it with the drill. I'm not sure what the gauge of the wire is. I've included some pictures from the sheathing where I could see it. I think it is #1 or #2 aluminum. Based on the fact that it supplies the entire dwelling, I think the cable needs to be rated for 83A, even though it is a 100A service. I've learned in the past on this forum that "2AWG aluminum SE is allowed to carry 90A when terminated on 75°C lugs as per 338.10(B)(4)(a)".
I would like to repair the cable, and I'm thinking that the inline splicers from Polaris can be used for this, specifically a ISR-1/0. I would need to put a box around this to make it an accessible junction box. Would this be an acceptable permanent repair, or are there better ways to fix this cable? And what do you think is the gauge of the cable?