3
Safety concept
Drive safety functions
Manual – MOVISAFE
®
CSB51A Safety Option
15
3.7.2
SS1(c) – Safe Stop 1 with time control
When the SS1(c) function is active, the inverter brings the motor to a standstill electri-
cally. The drive safety function STO is triggered after a specified, safety-related time.
This drive safety function corresponds to a controlled stop of the drive according to
EN 60204-1, stop category 1.
t
2
t
1
t
V
∆
t
9007201225618443
= Drive safety function monitoring
= STO drive safety function active
v
= Speed
t
= Time
t
1
= Point of time when SS1(c) is activated and motor deceleration is triggered.
t
2
= Point of time when STO is triggered.
Δt
= Safety-relevant period of time
INFORMATION
•
The SS1(c) function does not monitor the stopping of the drive.
•
The safety-related period of time Δt allows the drive to come to a stop. In the
event of a fault, the drive does not come to a stop and becomes de-energized at
the time t
2
(STO).
25931075/EN – 04/2019
