Lenze 8400 - Feedforward Control of the Motor before Release

Lenze · 8400 HighLine · Reference manual · DMS 12.0 EN · 06/2017 · TD23 621
8 Basic drive functions (MCK)
8.12 Holding brake control
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
8.12.6 Feedforward control of the motor before release
The motor is precontrolled by selecting the lower speed threshold for applying the brake (control
modes without feedback). When the upper speed threshold for brake release is reached, the motor
is precontrolled with the for the release time set in C02589
with the lower threshold value before
the brake switches to the release mode.
Here, the direction of the feedforward control depends on two conditions:
1. On the settings selected under C02582
:
• Bit 2 = feedforward control inverted (for vertical drives/hoists)
• Bit 3 = direction of the axis
2. On the sign of the setpoint.
Truth table for the direction of the feedforward control
Setpoint Direction Feedforward control Scheme Direction
Feedforward
control value
Start value
n ≥ 0 vertical/hoist
(C02582
: Bit 3 = 0)
not inverted
(C02582: Bit 2 = 0)
inverted
(C02582
: Bit 2 = 1)
n < 0 not inverted
(C02582
: Bit 2 = 0)
inverted
(C02582
: Bit 2 = 1)
n ≥ 0 horizontal/winding drive
(C02582
: Bit 3 = 1)
Inversion via bit 2 with
horizontal direction not
effective
n < 0
0
P
Q
0
P
Q
0
P
Q
0
P
Q
0
Q
0
Q