ABB SCU200, Руководство пользователя

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SCU200
INSITE ENERGY MANAGEMENT SYSTEM
7.1.5.Modbus TCP/RTU readings
SCU200 offers read/write operations on added peripheral RTU devices via external Modbus TCP
connection.
Modbus TCP configuration page is available under System setup->Communication->Modbus. In order to
enable communication user should enable Modbus TCP Disabled/Enabled switch and adjust TCP port
number if necessary. Port 502 is used by default
SCU200 acts as Modbus RTU router and has neither static registers map nor its own modbus ID. In order
to query a device, user should use connection parameters, IDs, functions and addresses exactly as it
would be used in case of querying a device directly.
For example, in order to read configuration of IO module with modbus ID 3, user should send request
using function 03 (read holding registers), slave ID 3, address 40 and size 1.
Similarly, reading Voltages L1, L2 and L3 in EQ meter with modbus ID 35, user should send request using
function 03 (read holding registers), slave ID 35, address 23269 and size 6.
By analogy, in order to query any other RTU device user should look up registers map in queried device
manual.
There’s no possibility to query multiple device with one request.
SCU200 supports following Modbus function codes:
01 – Read coils
03 – Read holding registers
05 – write single coil
06 – Write single register
15 – Write multiple coils
16 - Write multiple registers
When connection is idle, meaning, Modbus client is connected to SCU200 but no requests are exchanged,
SCU200 will drop such a connection after 60s. The connection could be reestablished normal.