6.1.2 Modbus/TCP and Modbus/RTU
The device supports both Modbus/TCP and Modbus/RTU communication. Modbus/TCP uses the
Ethernet connection to communicate with Modbus/TCP clients. Modbus/RTU is a serial protocol that
can be selected for the available serial ports.
The following Modbus function types are supported:
• Read multiple holding registers (function code 3)
• Write single holding register (function code 6)
• Write multiple holding registers (function code 16)
• Read/Write multiple registers (function code 23)
The following data can be accessed using both Modbus/TCP and Modbus/RTU:
• Device measurements
• Device I/O
• Commands
• Events
• Time
Once the configuration file has been loaded, the user can access the Modbus map of the relay via the
AQtivate software (
Tools
→
Communication
→
Modbusmap). Please note that holding registers start
from 1. Some masters might begin numbering holding register from 0 instead of 1; this will cause an
offset of 1 between the relay and the master.
Table. 6.1.2 - 226. Modbus/TCP settings.
Parameter
Range
Description
Enable Modbus/
TCP
0: Disabled
1: Enabled
Enables and disables the Modbus/TCP on the Ethernet port.
IP port
0…65 535
Defines the IP port used by Modbus/TCP. The standard port (and the default
setting) is 502.
Event read mode
0: Get oldest available
1: Continue previous
connection
2: New events only
0: Get oldest event possible (Default and current implementation)
1: Continue with the event idx from previous connection
2: Get only new events from connection time and forward
Table. 6.1.2 - 227. Modbus/RTU settings.
Parameter
Range
Description
Slave address
1…247
Defines the Modbus/RTU slave address for the unit.
Additionally, the user can adjust the measurement update interval with the following parameters (found
at
Measurement
→
Measurement update). These parameters do not affect the operating times of
protection functions, only the frequency of measurement reporting to Modbus.
Table. 6.1.2 - 228. Settings for measurement update interval.
Name
Range
Step Default
Description
Current measurement update
interval
500…10
000ms
5ms
2
000ms
Defines the measurement update interval of all current-
related measurements.
Voltage measurement update
interval
500…10
000ms
5ms
2
000ms
Defines the measurement update interval of all voltage-
related measurements.
A
AQ
Q-T215
-T215
Instruction manual
Version: 2.04
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