LS ELECTRIC SV-iS7 Series, User Manual

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Safety Funtion STO(Safe Torque Off)
Safet
y
Func
tio
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14 Safety Funtion STO(Safe Torque Off)
The iS7 Inverter series provides resilient safety features via optional safety expansion module.
When an emergency arises, it instantly blocks inverter output to protect the operator and
reduce the risk.
14.1 Safety Standard Product
The performance levels for the safety function are as follows.
EN ISO 13849-1: Category 3, PL Class d
EN 61508: SIL 2 (EN 60204-1, Stop Category 0)
When using the safety function, perform a risk assessment for the system and ensure that it meets
the safety requirements.
Note
When wiring the inverter or performing maintenance, the inverter must be turned off. The safety
function is not used to block the power supply to the motor or insulate the inverter electrically.
14.2 About the Safety Function
The safety function is a safety torque off (STO) function used to prevent a torque and to block
the power supply to the motor by interrupting the gate using hard wires.
STO (Safety Torque Off): IEC61800-5-2
The STO function is independently connected to each input signal for 2 channels (SE(SFT11) and
SP(SFT2)). The connected circuit cuts off the operation signal for the inverter output and turns
off the power modules.
If the safety function is activated during operation, the inverter blocks the output and the
motor enters Free Run mode. Also, the
“Safety Opt Err” message is displayed on the keypad.
To release the fault trip, short-circuit terminal block to return to the normal operation status
and press the [STOP/RESET] key.