The Freelance 800F system connects the process station, operator station and engineer station in the system through the system bus. The system bus fully complies with DIN/ISO 8802, Part 3 (IEEE802.3) Ethernet standard, and can use twisted pair, optical fiber or coaxial cable. The system bus can also use this standard to connect to 100Mbit/s network equipment to improve the communication speed of the system backbone network.

Freelance uses acknowledgment and non-acknowledgment service mechanism, non-acknowledgment UDP service mechanism is used for data update of horizontal communication between controllers, and TCP/IP service mechanism with acknowledgment is used to archive alarms and trends. The system bus has the following characteristics: long-distance transmission; High data flow; Different transmission media can be selected (such as twisted pair, coaxial cable or optical fiber); Flexible network structure; Through OPC standard, it is very convenient to connect the higher-level plant-level management system; Automatically start the pre-programmed route switching network in case of failure; Excellent EMC electromagnetic compatibility; During operation, switch whether the bus contact is running or stopping; High performance, redundancy

CAN bus When Freelance rack I/O is used, it is necessary to communicate with the controller through CAN bus. The bus follows the CAN (Controller Area Network) industry standard. The CAN bus has the following characteristics: realizing medium and short distance transmission; It can carry a large amount of data, and the signal update time is 2ms (digital quantity) or 10ms (analog quantity); High-level data transmission security (Hamming distance=6); Automatically start the pre-programmed route switching network in case of failure; Excellent EMC electromagnetic compatibility; The number of bus nodes can be switched during operation; The newly installed module can be initialized automatically

OPCFreelance 800F provides an OPC gateway (server) that allows OPC clients to access data and alarm information from Freelance process station. Before Freelance version 7.1, OPC also allows access to DPV1 parameters and user parameter information of Profibus and HART devices. If it is a HART device, it can only be accessed when the S900 I/O station is connected. After Freelance version 8.2, the parameters of the FOUNDATION Fieldbus field device can also be accessed.

DigiVis operator station integrates OPC client, allowing users to access data from external OPC server. For example, through OPC client, data from Siemens controller can also be integrated into DigiVis custom graphics.

Several OPC gateways can be used in Freelance system, and OPC server redundancy can also be realized. Control Builder F engineering software supports redundant OPC server configuration.

The trend server option provides a special OPC gateway, which is used to use the user-defined trend display on the DigiVis operator station. The access method of the trend server is“ Read Only”, All trend variables can be automatically generated. Each Freelance system can be configured with a trend server.