ACS 400 User’s Manual 141
The Control Word and the Status Word
Holding registers: 40001 (Control Word), 40004 (Status Word)
The Control Word (CW) is the principal means for controlling the drive from a fieldbus system. It is
effective when
• The drive is in external (remote) control and the controlling commands are received through
serial communication channel (set by parameters 1001 EXT1 COMMANDS, 1002 EXT2 COM-
MANDS and 1102 EXT1/EXT2 SEL), and
• Serial communication channel that is used for the controlling is Standard Modbus (parameter
5006 COMM COMMANDS is set to 1 (
STD MODBUS).
The Control Word (detailed in Table 22) is sent by the fieldbus master station to the drive. The drive
switches between its states according to the bit-coded instructions of the Control Word. See also
state machine on CROSSREF.
The Status Word (SW) is a word containing status information, sent by the drive to the master
station. The composition of the Status Word is explained in Table 24.
Note! Operation of Control Word and Status Word conforms to ABB Drives Profile with the
exception of Control Word bit #10 (REMOTE_CMD), which is not used by the ACS 400.
Table 22 The Control Word. See also the state machine in Figure 58 on page 147.
Bit Value Description
01Enter
READY TO OPERATE
0 Emergency OFF. Ramp to stop according to parameter 2203 DECELER TIME 1. Enter OFF1
ACTIVE; proceed to READY TO SWITCH ON unless other interlocks (OFF2, OFF3) are active.
1 1 Continue operation (OFF2 inactive)
0 Emergency OFF, coast to stop.
Enter
OFF2 ACTIVE; proceed to SWITCH-ON INHIBITED.
2 1 Continue operation (OFF3 inactive)
0 Emergency stop. Drive ramps to stop according to parameter 2205
DECELER TIME 2. Enter
OFF3 ACTIVE; proceed to SWITCH-ON INHIBITED.
3 0 -1 Enter
OPERATION ENABLED (Note that also the Run enable signal must be present on a
digital input – see parameter 1601
RUN ENABLE).
0 Inhibit operation. Enter
OPERATION INHIBITED
4Unused.
5 1 Normal operation.
Enter
RAMP FUNCTION GENERATOR: ACCELERATOR ENABLED
0 Halt ramping (Ramp Function Generator output held)
6 1 Normal operation. Enter
OPERATING
0 Force Ramp Function Generator input to zero.
7 0 - 1 Fault reset (Enter
SWITCH-ON INHIBITED)
0 (Continue normal operation)
8 to 10 Unused
11 1 Select external control location 2 (
EXT2)
0 Select external control location 1 (
EXT1)
12 to 15 Unused
http://nicontrols.com
To Next Page
Loading...
