3
Safety concept
Drive safety functions according to EN 61800-5-2
Manual – MOVISAFE
®
CS..A Safety Card (Version 2)
23
3.7.6
SS2(b) – Safe Stop 2 with monitoring of the deceleration ramp
When the SS2(b) function is active, the drive inverter brings the motor to a standstill e-
lectrically. The deceleration is monitored. The position must be safely monitored after
standstill (SOS function according to EN 61800-5-2). The STO drive safety function
will be triggered if the deceleration value is exceeded while stopping or if movement
occurs during standstill. STO means that standstill has to be ensured by a mechanical
brake.
This drive safety function corresponds to a controlled stop of the drive according to
EN 60204-1, stop category 2.
t
V
t
1
t
2
9007201225698059
= Drive safety function monitoring
= STO drive safety function active
v
= Speed
t
= Time
t
1
= Point in time when SS2(b) is activated and motor deceleration is triggered.
t
2
= Time when SOS is triggered.
28482271/EN – 03/2019
