If your dog is very high-energy or has very high food motivation and won't keep away from the beacon during training, there are a few things you can try which will help your dog calmly keep their focus* while training:

1. Try a more energy-draining exercise (such as taking them on a long walk, or putting a weighted backpack on your dog) before training to increase the effectiveness of their workout.
2. Practice leadership exercises with your dog, like encouraging your dog to follow you. One way to do this is to walk around with your dog to encourage them to follow your lead. This will help you to establish a partnership and encourage your dog to pay attention to you on a consistent basis. 
3. Re-evaluate your training setup; For example, if you just have an open plate sitting on the floor, it may make your dog more competitive. This is because your dog may interpret the food in front of them as a game or a challenge, which may increase their motivation to obtain the food item. Instead, try one of the following:
   • Try using a mostly-enclosed container that restricts your dog's vision (therefore decreasing their likelihood of fixating on obtaining the high-value food item), while still leaving enough of an opening to allow the scent to come through the container.
   • Try using a taller container, like a bucket or trash can, that is approximately chin-height for your dog. This will make it more difficult for your dog to get the food, meaning that they will have more time to process the prompts. This will increase the likelihood that your dog will build a keep-away association. 

Additional Notes

*The goal of achieving calm "focus" is to help your dog calmly keep their attention on the task at hand (in this case, learning to keep away from the food or high-value smell), and not to cause fixation on the food item. Fixation is characterized by an intense, suspenseful focus where your dog's motive is to obtain the food by waiting and/or watching intently. This exercise is designed to help you teach your dog to keep away, not to 'wait for an opportunity' to obtain the food.