I do not know for sure, but it shouldn't be too hard to do a back-of-an-envelope calculation:

Length of brake lever (pivot to hand contact) ~4"
Length of cable actuation arm (pivot to cable anchor) ~1"

So there is a 4:1 ratio of cable tension to hand force. I estimate that the maximum force a rider can generate is about 50lbs (it is difficult to hold a 50 lb object with your fingers)

So maximum cable tension is probably about 200 lbs.

V-brake levers pull with less force than canti or road levers.