Operation Time Scheme - ABB ACS800 Firmware Manual

Operation time scheme

The time scheme below illustrates the operation of the brake control function. See
also State shifts
Start command
External speed
reference
Inverter modulating
Motor magnetised
Torque proved
Open brake
command
Internal speed
reference (actual
motor speed)
Torque reference
T Start torque at brake release (Parameters
s
or AI or as per selection of Par. 42.07)
t Motor magnetising delay (Par. 21.02, Constant DC Magn time)
md
t Brake open delay (Parameter 42.03, Speed reference delay and brake ackn DI
od
supervision delay)
n Brake close speed (Parameter 42.05, Absolute brake close speed level)
cs
t Brake close delay (Parameter 42.04, Torque ON time during closing of mechani-
cd
cal brake and brake ackn DI supervision time)
t Torque proving time period
trqpv
T Torque proving reference. Fixed as 30% positive torque reference.
pv
t Extended run time (Parameter 42.09, Magnetising ON after brake close)
extmt
on page 114.
1
t
md
t
trqpv
t
od
3
T T
s
pv
20ms
42.07
5
4
and 42.08 from torque memory
t
extmt
t
cd
6
n
cs
Program features
113
7
time