SMAC CBC-EIP, User Manual, Page: 9 / 42

9
mode. The generated software fault cannot be reset until a power supply reset is performed.
Figure 2.4 illustrates the abnormal STO operation.
Table 2.2 summarizes the STO modes that are previously described.
Figure 2.3. Timing diagram of CBC-ECT STO.
Figure 2.4. Illustration of the abnormal STO operation.
Table 2.2. Summary of STO modes.
Mode Status STO1
input STO2
input Power
stage STO
FB Drive function
Normal
operation STO ACTIVE 0 0 Disabled 0 Drive cannot start or
provide power to motor
STO
INACTIVE 1 1 Enabled 1 Drive is enabled to run
under firmware control
Diagnostic STO ACTIVE
PULSE (1 ms
< t < 23 ms)
x 0 Enabled 0 A short STO ACTIVE (“0”)
pulse does not stop the
motor operation.
However, it activates STO
FB. It can be used for
performing system
diagnosis.
STO ACTIVE
PULSE (1 ms
< t < 23 ms) 0 x Enabled 0
Time
STOx
input
STO_FB
output
Power
stage state
0 800 ns
23 ms
Logic level
Time
STO1
input
STO2
input
Power
stage state
0 23 ms 0.6 s < T
latching
< 2.6 s
Logic level