The STS electricity meter does not communicate directly with the backend vending system. Instead, it incorporates an STS prepayment algorithm internally. The vending process also adheres to this identical algorithm. The software generates a 20-digit token that encapsulates specific details such as the meter ID, recharge amount, and encryption key, ensuring that each token is uniquely crafted. This unique token is designed to be accepted exclusively by the designated meter, enabling the corresponding credit to be applied.
