Ecollars are not meant to be punishers. Of course they may prevent chewing. And chewing electrical cords can be deadly. When you have puppies it may be a good idea to thread them through PVC pipe to avoid the puppy getting to them. Is the puppy doing this in your presence? How closely are you supervising? I would tether her to me or have her somewhere safe (no electral appliances) when you are unable to keep an eye on her. Shouting at her (especially after the fact) doesn't work. But interrupting her when she's just getting started (because you are supervising her and notice) can help.