Delta C2000 Series User Manual page 647

Chapter 17 Safety Torque Off Function
17-1 The drive safety function failure rate
Item
Safe Torque Off
SFF
HFT (Type A Hardware Fault Tolerance
subsystem)
Safety Integrity Level
SIL
Average frequency of dangerous
PFH
failure [h-1]
Probability of Dangerous Failure on
PFD
av
Demand
Category Category
PL Performance level
MTTF Mean time to dangerous failure
d
DC Diagnostic coverage
17-2 Safety Torque Off terminal function description
The safety Torque Off function is to cut off the power supply to motor through the
hardware,
thereby the motor couldn't produce torque.
The safety Torque Off function is respectively by two independent hardware to control the
motor current drive signal, and thus cut off the inverter power module output in order to
achieve the status of safety stop.
Operation principle Description as below table 1:
Table 1: Terminal operation description
Signal
Channel
STO1~SCM1
STO
signal
STO2~SCM2
Driver Output status
STO means Safe Torque Off
STL1~STL3 means Safety Torque Off hardware abnormal.
STL3 means STO1~SCM1 and STO2~SCM2 internal circuit detected abnormal.
STO1~SCM1 ON(High): means STO1~SCM1has connect to a +24VDC power supply.
STO2~SCM2 ON(High): means STO2~SCM2 has connect to a +24V power supply.
STO1~SCM1 OFF(Low): means STO1~SCM1hasn't connect to a +24VDC power supply.
STO2~SCM2 OFF(Low): means STO2~SCM2hasn't connect to a +24VDC power supply.
C2000 Series
Definition
Photo-coupler status
ON(High) ON(High)
ON(High) OFF(Low)
STL2 mode
Ready (Torque
output off)
17-2
Standard Performance
Channel 1: 80.08%
IEC61508
Channel 2: 68.91%
IEC61508 1
IEC61508 SIL 2
IEC62061 SILCL 2
IEC61508 9.56×10
IEC61508 4.18×10
ISO13849-1 Category 3
ISO13849-1 d
ISO13849-1 High
ISO13849-1 Low
OFF(Low)
ON(Low)
STL1 mode
(torque (Torque output
output off)
-10
-6
OFF(Low)
OFF(Low)
STO mode
off)