Delta MH300 Series - 17-1 Basic Function Description

Chapter 17 Safe Torque Off FunctionMH300
17-2
17-1 Basic Function Description
The MH300 series provides a Safe Torque Off (STO) function. The MH300 series uses dual-channel
S1 and S2 signal inputs to turn off IGBT switching, further preventing the generation of motor torque in
order to achieve a safe stop. Refer to Figure 1 for the Safe Torque Off function circuit diagram.
The MH300 Safe Torque Off function meets the following international standards:
 ISO 13849-1: 2015 Category 3 PL d
 IEC 61508 SIL2
 EN 62061 SIL CL 2
 EN 60204-1 Category 0
Line
Driver
GU
GV
GW
GX
GY
GZ
Gate
Driver
IGBT Power Section
Motor
STO Functional Block Of Subsystem 3
+3.3V
+3.3V
+3.3V
A
B
C D
G
F
FDBK
MO2
MCM
RC
RA
1
2
3
S1
DCM
S2
DCM
R1
R2
R3
MCU
AC power
Line
Driver
2
SU1
SV1
SW1
SX
SY
SZ
SU
SV
SW
R4
4
+3.3V
D EC
Reset
IC
+3.3V
Channel A (safety)
Channel B (safety)
Diagnostic path
Non-safety pat h
Safety PLC
Emergency
Stop button
+24VDC
Fig.17
-1 The circuit diagram for the Safe Torque Off function