Siemens SINAMICS S120 Manual page 34

3 DCC Blocks
goes away, and the load is not yet on the ground (suspended load), and the travel
command is cancelled, the brake will attempt to close. Once the brake closes, if the
brake continues to slip, then again, the inverter(s) switched on and the entire
process is repeated. Once the load is on the ground, the cause of the brake slip
should be investigated.
User takes all responsibility for configuration and use of
BrakeSlipDetection
An inverter holding a suspended load for too long will cause thermal stress and
WARNING
possibility of premature failure of IGBT which would cause the drive to fault out,
and material damage as well as injury to personnel can occur.
To avoid putting too much stress on the inverter(s) once the brake slip alarm
(A51061) is active, load must be lowered as soon as it is safe and possible.
Ensure proper encoder operation
If encoder fault occurs during a brake slip condition, drive will respond with
encoder fault response which may result in brakes attempting to close. If brake
WARNING
was already slipping, this may result in the load falling to the ground.
Ensure encoder is operating properly and well maintained.
Connections
Table 3-9-1 Brake Slip Detection connections
SINAMICS
parameter
number
p21960 boEnable
p21961 rActualSpeedH1 (r63.1)
p21962 rActualSpeedH2 (r63.1)
p21963 rBrakeSlipSpeedThreshold
(%)
p21964 rBrakeSlipDetectDelayTime
(ms)
p21965 rAlarmOffAfterTravelCommand
DelayTime (ms)
Extended Crane Drive-Based Technology AC
Extended Crane Drive-Based Technology SINAMICS S120
DCC Add-On Description 109767457,
Name Connection
type
V1.2, 09/2019
Default
assignment
IN 0
IN 0
IN 0
IN 1
IN 500
IN 2000
Data Meaning
type
BOOL Enables
BrakeSlipDetection
Connect r63[1] (CO:
REAL
Speed actual value,
Smoothed with p0045)
from hoist 1
REAL Connect r63[1] (CO:
Speed actual value,
Smoothed with p0045)
from hoist 2 if there is a
secondary hoist, if not
keep 0.
REAL Maximum allowable
speed
REAL Maximum allowable
time for which actual
speed can be larger
than the brake slip
speed threshold.
Time for which travel
REAL
command must be
present for to reset the
alarm A51061.
34