ABB MRP31.0, Техническое описание

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Technical description MRP31.0
Issue: 09.2014
Electrical installation
Modbus Connection
Connect Modbus to X3.
General cabling instructions
– Arrange the bus cables as far away from the motor cables as possible.
– Avoid parallel runs
– Use bushings at cable entries
Connector X3
PIN Description
1 Bus cable shield. Connected internally to
GND via a capacitor.
2
3 GND. Isolated signal ground
4 Data A (inverting)
5 Data B (non inverting)
Bus termination
Bus termination is required to prevent signal refl ections from the bus cable ends. The MRP31 Modbus interface module is not
equipped with internal bus termination
Termination with an external termination resisotor of 120
액
between Data A and Data B should
be foreseen on devices located at bus ends.
Master supervision
It is possible to confi gure a maximal time without telegrams from the master before the UMC100.3 triggers the confi gured
busfault reaction. This time has to be set in the UMC100.3 using the UMC100.3 LCD panel. By default no timeout is set.
Setting the Communication Parameters
The Modbus interface module does not provide means to adjust the Modbus slave address and baud rate. The Modbus slave
address baud rate and communication timeout can be set in the UMC100.3 and are copied to the Modbus interface module
during initial connection between UMC and MRP31. When changing communication parameters later on perform a power cycle.
If the MRP31 is used with an old UMC100 (e.g. UMC100 R101/R201), then the baud rate is
automatically set depending on the bus address.
See the MRP21 manual for additional information.
Number of nodes in a Modbus network
Each bus segment can have a maximum of 32 active devices which includes the Modbus master and and the slaves.
Network length
The end-to-end length of the Modbus network is limited. The maximum recommended length is 1000 m. The use of passive bus
stub lines should be avoided. To bridge long distances between the Modbus master and the salves (e.g. between the control
room and the motor control center) it is recommended to use fi ber optic converters.
Recommended Types: ILPH RS 485 / FO from ABB
For integrating Modbus devices into a Modbus TCP network ABB offers a Serial/Ethernet gateway. Recommended Type
is eILPH. For the UMC100.3 a direct integration into a ModbusTCP network is available with the MTQ22 device.