Modbus Constructor comes with a special freeware utility Modbus Reader, which operates using the model created with Modbus Constructor used to interact with your devices.Modbus Reader is a free tool which can run several projects at the same time, i.e. query or simulate several devices using one or more COM-ports.The software supports several protocols, including Modbus over TCP/IP, Modbus RTU or ASCII and allows you to perform data logging for multiple devices at once.If you have already created a Modbus Constructor project for the device you designed, your clients will not have to purchase Modbus Constructor: it is enough just to download a freeware Modbus Reader.