No, the point of having it protected is that it won't be affected even if you cause an accident.
Your NCB will be unaffected but your premium would still go up because you would now have a claim on your record, meaning you are considered a higher risk.
I was surprised to find out that if I were to have an accident my 4 years NCB would just be halved rather than restarted at zero with my current insurers, admiral.
As I work at an insurance company I feel like I should finish with a disclaimer at the end of this post that all insurance companies work differently and to check with the company you are dealing with as to how it works with them.