LC1200 IO Module I/O Coupler Bus Extended Analog Input Modbus-TCP

Coupler Wiring with MODBUS Master Station，Connect the coupler LC1200 to the MODBUS master station using an Ethernet cable. Set the dip switch on the coupler according to your needs. The Modbus TCP coupler module has a set of dip switches used to configure the last three digits of the coupler module’s IP address.

Set the IP address, subnet mask, and gateway address information for the computer running the configuration software. The computer’s IP address is 192.168.1.1, and the subnet mask is 255.255.255.0. Set the IP address for the LC1200 station. The factory default address for the LC1200 is 192.168.1.xxx, with the last three digits set via the dip switches, ranging from 1 to 254 (the slave IP address cannot be the same as the master station’s). The address configuration must be completed before powering on, with each dip switch corresponding to specific data.

Open the ModbusPoll software, then select “File -> New” from the menu bar. Click on Connection to configure the connection information:

Set the connection target to Modbus TCP/IP.

Set this IP address to 192.168.1.2 according to the dip switch values.

Set the Server Port to 502.

The LC1200 supports four types of communication and corresponding starting addresses. The channel address allocation rules for the LC1200 are based on the topology of LC1200 + LC1488 (LC1408) + LC1486 (LC1406) + LC2488 (LC2408) + LC2486 (LC2406) + LC1188 (LC1088) + LC3134 + LC4134 + LC3114 (LC4114) + LC3162 + LC3172 + LC3184, with each IO module channel corresponding to a Modbus TCP address.

Note 1: If there is a communication error with the IO module during operation, the error information will be stored in the holding register at address 999. For example, if the first card has a communication error, the error code will be 0x100; for the second module, it will be 0x101, and so on.

Note 2: The type values corresponding to each module are shown in the table. The holding register addresses from 1000 to 1015 (16 registers in total) are used to store the module types. Each 8 bits represent a module type value in the order of the modules connected to the LC1200, allowing for the storage of type values for up to 32 modules.

Note 3: The target subnet values are written to the holding registers at addresses 1016 to 1019. The subnet modification command 205 (0xCD) needs to be written to the holding register at address 1019 to complete the subnet modification. The default subnet for this module is 192.168.1.xxx. If it needs to be changed to 193.169.2.xxx, the register content must be written accordingly.

The LC1200 supports subnet modification. The factory default address for this module is 192.168.1.xxx, with the last three digits set via the dip switches. If the user needs to change the subnet to 193.169.2.xxx, operations on the holding registers at addresses 1016 to 1019 are required as shown in Table 3-4:

(1) First, establish a network connection between Modbus Poll and the LC1200 using the default factory subnet value.

(2) As shown in the figure, sequentially write values to registers 1016 to 1019, where registers 1016 to 1019 contain the new subnet values, and register 1019 contains the modification command. If the subnet value is written incorrectly, first set the value of register 1019 to “0,” then sequentially write the values starting from register 1016. After successfully modifying the subnet value, the user needs to restart the LC1200. The computer and Modbus Poll subnet must be changed to the user-defined subnet value, and the dip switch values can only be set between 2 and 253.

(3) If the user forgets the modified subnet value, they need to restore the LC1200’s subnet value to the factory setting of “192.168.1.xxx.” The user should set the dip switch value to “254” and power on the device. At this point, the LC1200’s IP will be “192.168.1.254,” allowing the user to reset the subnet value following steps (1) and (2).