FIELDBUS COMMUNICATION 3.3.2. Control word The control word register is used to control the motor. This registers can be used as an alter- native to using the digital output telegram (section 3.2). Read control word using Modbus function code 3 Read Holding Registers or 4 Read Input Registers Write control word using Modbus function code 6 Write Single Register or 16 (10h) Preset Multiple Registers. Protocol Address Bit Data Description 0400h 0 Reserved 1 Stop Commence a stop when this bit is set (this bit has higher priority than the start coil). The stop bit is only acknowledged if the Auto mode bit is set. 2 Start Commence a start when this bit is set.
The start is only acknowledged if the Auto mode bit is set. 3 Reserved 4 Reserved 5 Auto mode This bit must be set for controlling the motor. 6 Fault reset Reset an active fault or protection when this coil is set. 7 Reserved 8 Reserved 9 Reserved 10 Reserved 11 Reserved 12 Clear active diag- nostics Clear active diagnostics when this coil is set (regis- ter 2000h and 2003h will be cleared). See section 3.5.1 13 Reserved 14 Reserved It is recommended to give the start/stop commands to the Softstarter using bit 1, 2 in the control word or protocol address 0101h, 0102h. Which of these registers that will be acknowl- edged by the device depends on the auto mode configuration.
15 Reserved If auto mode is set using protocol address 0105h, then the start/stop commands can be given using protocol address 0101h, 0102h. But if bit 5 in the control word (protocol address 0400h) is set, then the start/stop commands can be given using bit 1, 2 in the control word. However if auto mode is set in both protocol address 0105h and bit 5 in the control word, then start/stop commands will not be acknowledged by the device due to incorrect configu- ration. © Copyright 2019 ABB. All rights reserved. STATUS Approved SECURITY LEVEL Public DOCUMENT ID. 1SFC132367M0201 REV. B LANG. en PAGE 8/22