MSG11-5715-743/EN: AC20F Series - Hardware Installation Manual
MSG11-5715-743/EN 24.04.2023
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Input State Truth Table
STO Input
Channel A
STO Input
Channel B
STO Status
Description
0V
0V
STO ACTIVE
Inverter cannot start or supply power to the
connected motor.
STO trip reported by the inverter.
24V
0V
STO ACTIVE
(Abnormal one-
channel operation
detection)
Inverter cannot start or supply power to the
connected motor.
STO trip reported by the inverter.
If either of these conditions persists for more
than 1sec, the STO function
can
lock into a
Fault state.
If either of these conditions persists for more
than 5sec, the STO function
will
lock into a
Fault state.
Once in the Fault state, the inverter cannot
start until it has been power cycled (both
mains power and any auxiliary 24V supply).
0V
24V
24V
24V
STO INACTIVE
Inverter is enabled to run and supply power
to the connected motor under software
control.
X
X
INVERTER
UNPOWERED
Inverter cannot start or supply power to the
connected motor.
Example Applications
WARNING!
Diagrams are for Illustration only:
The wiring examples shown in this section are for illustration only. They
are not to be considered as ‘final’ designs, nor as an attempt to create a
design for specific solutions. The user / installer is responsible for
designing a suitable system to meet all requirements of the application
including assessing and validating it. Parker will not accept any liability for
failure to do this or any consequential loss or damage.
Applications NOT Requiring STO Functionality:
The example below shows the drives’ 24V output voltage used to permanently wire the STO inputs in the
‘High’ state, i.e., STO
DISABLED
(drive operational):