1. The problem statement, all variables and given/known data 2. Relevant equations Number of encirclements = Number of open loop poles - Number of Close loop poles on Right side of S plane. 3. The attempt at a solution There is 1 open loop pole on RHS For Close loop poles I used Routh Herwitz method and got 1 pole on RHS. 1 sign change. So I get N = 0. Where am I wrong?