Operation Principle - ABB Q957 User Manual

16 Option description
Note: ACS880-07/07LC drives, frames n×DXT + n×R8i with a main contactor/breaker (option
+F250/+F255), ACS880-17/17LC/37/37LC drives, frames n×R8i + n×R8i, and ACS880-17/37
drives, frames R8 and R11: When the inverter unit STO is activated, the main
contactor/breaker is opened after a user-defined delay (defined with parameter 94.11, the
default value is 600 s). See the hardware and firmware manuals for more information.
For a detailed description of the drive STO function, see the hardware manual.
The design principles of the option +Q957 comply with EN ISO 14118. The STO function
complies with IEC/EN 61800-5-2. For a complete list of related standards and European
directives, see section

Operation principle

The figure shows a simplified operation principle. For a more detailed description, refer to
the circuit diagrams delivered with the drive.
24 VDC+
-A65
-S
1
0
- - - The dashed line in the figure shows a user-defined installation.
A41 Inverter control unit
A65 POUS safety relay
S POUS switch (user-defined)
P POUS indicator lamp (user-defined)
T11.x Inverter module(s) under inverter unit T11 (only for R8i)
X969 STO terminal block
1) Reset (automatic)
2) To parallel inverter modules (if any)
3) Drive module
Step Operation
Initial status: The drive is in operation, but the motor is not running.
1 The user sets the POUS switch [S] to the open position. This activates the POUS function.
2 The POUS safety relay [A65] de-energizes the XSTO inputs IN1 and IN2 of the inverter control unit
[A41], which activates the drive STO function. The drive shows an indication.
3 The POUS indication lamp [P] comes on.
Related standards and directives (page
1)
-P
35).
-A41
-T11.x
XSTO
-X52 B
XSTO
.OUT
OUT OUT SGND SGND SGND SGND
SGND SGND IN2 IN2 IN2 IN2
IN1 IN1 SNGD SNGD SGND SGND
IN2 IN2 IN1 IN1 IN1 IN1
-X96 9 -X96 9
Main ci rcu it Main ci rcu it
3) 3)
~ ~
-X51 B
2)
SGND SGND
~ ~ ~
OUT2 OUT2
SGND SGND
OUT1 OUT1
M M M
3~ 3~ 3~