Siemens SIMATIC S7-200 - Drv_Ctrl

Using USS Protocol Instructions to Communicate with Drives
11-7
S7-200 Programmable Controller System Manual
A5E00066097-02
DRV_CTRL
The DRV_CTRL instruction is used to control an ACTIVE
MicroMaster Drive. The DRV_CTRL instruction places
the selected commands in a communication buffer.
Commands in the buffer are sent to the addressed drive
(DRIVE parameter), if that drive has been selected in the
ACTIVE parameter of the USS_INIT instruction. Each
drive should have only one DRV_CTRL instruction.
The EN bit must be on to enable the DRV_CTRL
instruction. Typically, this instruction is always enabled.
RUN (RUN/STOP) indicates whether the drive is on (1)
or off (0). When the RUN bit is on, the MicroMaster Drive
receives a command to start running at the specified
speed and direction. In order for the drive to run, the
following must be true:
 DRIVE must be selected as ACTIVE in USS_INIT.
 OFF1 and OFF2 must be set to 0.
 FAULT and INHIBIT must be 0.
When RUN is off, a command is sent to the MicroMaster
Drive to ramp the speed down until the motor comes to a
stop.
The OFF2 bit is used to allow the MicroMaster Drive to
coast to a stop. The OFF3 bit is used to command the
MicroMaster drive to stop quickly.
The F_ACK (Fault Acknowledge) bit is used to
acknowledge a fault in the drive. The drive clears the
fault (FAULT) when F_ACK goes from low to high.
The DIR (direction) bit indicates in which direction the
drive should move (0 - counterclockwise, 1 - clockwise).
The DRIVE (drive address) input is the address of the
MicroMaster Drive to which the DRV_CTRL command is
to be sent. Valid addresses are 0 to 31.
SPD_SP (speed setpoint) is drive speed as a percentage
of full speed (-200.0% to 200.0%). Negative values of
SPD_SP cause the drive to reverse its direction of
rotation.
Note
Only one DRV_CTRL instruction should be assigned to each drive.
L
A
D
S
T
L
F
B
D
CALL DRV_CTRL,RUN,
OFF2, OFF3,
F_ACK, DIR,
DRIVE,SPD_SP,
RSP_RCVD,ERR,
DRV_STAT,
DRV_SPD,
DRV_RUN,
DRV_DIR,
DRV_INH,
DRV_FLT
222 224
✓✓✓
221 226
✓
EN
RSP_R
ERR
STATUS
SPEED
RUN_EN
DIR_CW
INHIBIT
FAULT
DRV_CTRL
RUN
OFF2
OFF3
F_ACK
DIR
DRIVE
SPD_SP