Hitachi ABB RVT Installation Und Betriebsanleitung Seite 615

Contents
1. Introduction .................................................................................................................................................. 4
1.1. Intended audience ............................................................................................................................... 4
1.2. Before you start ................................................................................................................................... 4
1.3. How to use this manual ....................................................................................................................... 4
2. Overview ....................................................................................................................................................... 4
2.1. Introduction to Modbus ........................................................................................................................ 4
2.2. The Modbus adapter ........................................................................................................................... 4
2.3. Compatibility ........................................................................................................................................ 5
3. Serial interface considerations ................................................................................................................... 5
3.1. Communication mode .......................................................................................................................... 5
3.2. SINGLE ENDED versus DIFFERENTIAL data transmission ............................................................... 6
3.3. RS-232 interface .................................................................................................................................. 6
3.4. RS-422 interface .................................................................................................................................. 6
3.5. RS-485 interface .................................................................................................................................. 6
3.6. Bias resistors ....................................................................................................................................... 7
3.7. Termination resistors ........................................................................................................................... 7
3.8. Shielding and grounding considerations .............................................................................................. 7
3.9. Cable requirements ............................................................................................................................. 7
3.10. Network topology ................................................................................................................................. 8
4. RS485 Modbus adapter ................................................................................................................................ 8
4.1. Main features ....................................................................................................................................... 8
4.2. Physical dimensions ............................................................................................................................ 9
4.3. Mounting .............................................................................................................................................. 9
4.4. Technical data .................................................................................................................................... 10
4.5. Commissioning process .................................................................................................................... 10
4.6. To set the COMMUNICATION LOCK parameter ................................................................................ 11
4.7. To test the communication ................................................................................................................. 12
5. Modbus protocol overview ........................................................................................................................ 12
5.1. Overview ............................................................................................................................................ 12
5.1.1. Transactions on Modbus Networks ................................................................................... 12
5.1.2. Serial Transmission Mode ................................................................................................. 12
5.2. Data Addresses in Modbus Messages .............................................................................................. 12
5.3. Supported function codes .................................................................................................................. 13
6. Data access ................................................................................................................................................. 13
6.1. Access levels ..................................................................................................................................... 13
6.2. Minimum and maximum values ......................................................................................................... 14
6.3. Modbus Data table ............................................................................................................................ 14
7. Troubleshooting ......................................................................................................................................... 14
PREPARED
2022-09-29 Marie Pilliezt
APPROVED
TITLE
RS485 Adapter
OWNING ORGANIZATION
Capacitors and Filters
STATUS
Approved
DOCUMENT KIND
Manual
DOCUMENT ID
9AKK107045A9895
SECURITY LEVEL
Public
REV. LANG. PAGE
E en 2/21
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