MTL 8502-BI-DP Bus Interface Module (BIM)

MTL 8502-BI-DP Bus Interface Module (BIM)

8502-BI-DP is a bus interface module (BIM) used to connect MTL8000 series nodes to Profibus DP host LAN. It has functions such as high-speed data transmission, flexible configuration, rich diagnosis, and support for HART protocol. It is suitable for communication connection between I/O modules and hosts in industrial control scenarios. The following is a summary of the specific content:

Core functions and communication capabilities

Basic Connection and Expansion: As a communication bridge between MTL8000 series I/O modules and Profibus DP host, it supports up to 24 I/O module connections, providing support for the host to quickly respond to control conditions during the process.

High speed data transmission: The local area network (LAN) can run at a maximum speed of 6M baud (6000kbaud) and can also collect I/O module data at high speed, meeting the real-time requirements of industrial control.

Data and Protocol Support: Supports Profibus DP protocol, which can be used to transmit HART process variables and state variables; In addition to cyclic data exchange (used for reading and writing I/O data), it also supports Profibus extended diagnostic function, providing detailed information such as module and channel status to assist in high integrity operation and on-site maintenance of the system.

Configuration method

8502-BI-DP provides two main configuration methods to meet the setting requirements in different scenarios:

Configuration Method Tools/Dependency Core Features Applicable Scenarios

Parameterized configuration of Profibus configurator and GSD files is configured at the "module level", and all channel configurations under a single module are consistent; Configuration is based on "logical modules" (corresponding to physical modules), and modules need to be added one by one and parameters selected in the configurator; Support HART "email" function, collect HART variables as needed, and save telegram data space; When the session starts, the configuration is sent from the Profibus host to the BIM. After the system restarts, the configuration will be retransmitted to pursue configuration efficiency, and the channel requirements within the module will be unified

The software configuration 8455-SW-CF configuration software and 8510-MO-NS node service module support "channel level" independent configuration, and each channel and alarm can be set separately; Configuration can be stored in BIM or saved to the 8510-MO-NS module for quick recovery during BIM replacement; Using independent GSD files, data frames are constructed based on "data blocks", and the software automatically generates a telegram data mapping table for host programmers to identify data. It is necessary to flexibly set up a single channel or ensure that the configuration can be quickly restored in scenarios where data needs to be recognized

In addition, the address can be set through BIM software, the Profibus "Set Slave Address" command, or the switch settings of the 8510-NS-MO module; The 8510-NS-MO module also has automatic configuration function.

Data frames and diagnostics

1. Data frames occupy space

The input/output word occupancy of different data types in DP data frames is as follows:

Data Type Standards and Extended Diagnostic Input/Output Words

Analog data, 1 word per input channel, 1 word per output channel

Digital data, 1 word per input module, 1 word per output module

The two characters of each variable in HART are not applicable

HART status: 1 word per channel is not applicable

Meanwhile, the DP data frame size can be configured, with a maximum of 244 bytes; The maximum input data (including 2-byte status words) is 244 bytes, the maximum output data (including 2-byte control words) is 244 bytes, and the total input and output data is 296 bytes; The diagnostic telegram is fixed at 78 bytes.

2. Diagnostic function

Standard diagnosis: Provides routine Profibus status information to meet basic fault identification requirements.

Extended diagnosis: provides more detailed status data, including BIM's own status, I/O module health status, channel status (such as high and low alarms, open circuits, line faults, etc., depending on the type of I/O module); When anomalies occur and are cleared, extended diagnostic messages will be generated, and the host application needs to provide corresponding support to use them; If the host is unable to use diagnostic data in the control algorithm, the diagnostic data can be mapped to input data frames.

HART device maintenance

Support transparent communication with HART devices through local configuration ports and 8512 HART communication interface. Multiple BIMs can be connected to multiple stations on the RS485 bus and connected to PCs running various instrument management software, facilitating centralized maintenance and management of HART devices.

Hardware and electrical specifications

1. LAN interface parameters

Protocol and standards: Following Profibus DP (compliant with EN50170 standard), the transmission standard is RS485; The isolation between LAN, Railbus and power supply reaches 500V.