A1-User’s Manual
１９０
10.
Functional Safety
10.1
Functional Safety
10.1.1
Safety standard product
A1 offers safety option to reduce the risk of an emergency situation by off the VFD output
to protect the operator when using the machine. Performance level of safety features are
as follows
-
EN 61508: SIL 2
When using the safety function, make sure that the system of risk assessment need to be
carried out and if it meets the safety requirements
Operating wiring or maintenance, VFD must be turned off
Safety function is not electrically isolated or completely blocks the power of motor
10.1.2
Safety function description and wiring diagram
Safety function is STO function to cut off power supply from motor (Cutting off VFD output
current) by impeding gate with hard-wired and not to cause a torque
VFD cut off output when SA input closed or SB input open
STO function has 2 channels (SA, SB) the input signal is connected to independently. The
signal cut off the output of the VFD control circuit drive signal and power module. During
operation, safety function is activated, the VFD cut off the output and the status of motor
is
"
Free run
"
and message is displayed on the keypad (
"
Safety Opt Err
"
message) to turn off
the trip, when VFD of state is normal, press the reset key
