Siemens Simatic S7 Series System Manual

Libraries
9.2 USS library instructions
S7-200 SMART
System Manual, 09/2015, A5E03822230-AC
419
9.2.2.3
USS_CTRL instruction
Table 9- 7 USS_CTRL instruction
LAD / FBD
STL
Description
CALL USS_CTRL, RUN, OFF2, OFF3,
F_ACK, DIR, Drive, Type,
Speed_SP, Resp_R, Error, Status,
Speed, Run_EN, D_Dir, Inhibit,
Fault
The USS_CTRL instruction is used to control an
active Siemens drive. The USS_CTRL instruction
places the selected commands in a communications
buffer, which is then sent to the addressed drive
("Drive" parameter), if that drive has been selected in
the "Active" parameter of the USS_INIT instruction.
Only one USS_CTRL instruction should be assigned to each drive.
Some drives report speed only as a positive value. If the speed is negative, the drive reports
the speed as positive, but reverses the "D_Dir" (direction) bit.
The "EN" bit must be on to enable the USS_CTRL instruction. This instruction should always
be enabled.
Table 9- 8 Parameters of the USS_CTRL instruction
Inputs/outputs
Data types
Operands
RUN, OFF 2, OFF 3, F_ACK, DIR
BOOL
I, Q, M, S, SM, T, C, V, L, Power Flow
Resp_R, Run_EN, D_Dir, Inhibit, Fault
BOOL
I, Q, M, S, SM, T, C, V, L
Drive, Type
BYTE
VB, IB, QB, MB, SB, SMB, LB, AC, *VD, *AC, *LD, Constant
Error
BYTE
VB, IB, QB, MB, SB, SMB, LB, AC, *VD, *AC, *LD
Status WORD VW, T, C, IW, QW, SW, MW, SMW, LW, AC, AQW, *VD, *AC,
*LD
Speed_SP
REAL
VD, ID, QD, MD, SD, SMD, LD, AC, *VD, *AC, *LD, Constant
Speed
REAL
VD, ID, QD, MD, SD, SMD, LD, AC, *VD, *AC, *LD

Siemens Simatic S7 Series Specifications

General

CPU	Varies by model (e.g., S7-300, S7-400, S7-1200, S7-1500)
Communication Interfaces	PROFIBUS, PROFINET, Ethernet, MPI
Programming	TIA Portal, STEP 7
Programming Languages	LAD, FBD, STL, SCL, GRAPH
I/O Modules	Digital, Analog, Specialty modules available
Operating Temperature	0°C to 60°C (standard models)
Mounting	DIN rail mounting
Operating Voltage	24V DC or 120/230V AC (varies by model)
Protection Class	IP20 (standard models)
Memory	Varies depending on the S7 model. Includes work memory (RAM) for program execution, load memory (EEPROM or Flash) for program storage, and system memory for operating system functions. Memory sizes range from kilobytes to megabytes.