2 safe stop 1, ss1 – NORD Drivesystems BU0230 User Manual
Page 33
2 Description of function
BU 0230 GB-2712
33
2.3.2
Safe stop 1, SS1
With the SS1 function, the motor is first stopped by the inverter and after standstill the device switches to the
STO function. This method is the same as stop category 1 (controlled stop) as per IEC60204-1. Switching to
the STO function can be monitored after reaching standstill or can be carried out via a fail-safe timing relay
(delayed output of a protective switching device).
NOTE
Controlled braking is triggered via a digital input and only complies with low safety
requirements!
If controlled braking fails then the device switches over to STO.
If necessary, the braking process must be monitored.
NOTE
Control of a mechanical brake by means of the inverter is not fail-safe!
In case of failure of controlled braking, a mechanical brake connected to terminals 79 (MB+)
and MB-) may be overloaded, as this brake is applied when the STO function is triggered.
If necessary, slippage of lifting gear must be prevented by the use of suitable brakes.