4 commissioning – Lenze SCF frequency inverter User Manual
Page 46

46
Lenze 13466146 EDBSF01 v24 EN
4 Commissioning
HP
DEFAULT
HP
DEFAULT
"Normal"
Linear V/Hz
Ratio
V/Hz Ratio
Affected By
Fixed Boost
1/2 Base
Frequency
Base
Frequency
Full
Output
Volts
0.25 - 1
5.3%
10
2.4%
1.5 - 2
4.4%
15
2.2%
3
3.6%
20
2.0%
5
3.0%
25
1.8%
7.5
2.7%
30
1.6%
P29
ACCELERATION BOOST
ACCELERATION BOOST helps accelerate high-inertia loads. During acceleration, the output voltage
is increased to increase motor torque. Once the motor reaches the new speed setpoint, the boost is
turned off and the output voltage returns to the normal value.
P30
SLIP COMPENSATION
SLIP COMPENSATION is used to counteract changes in motor speed (slip) caused by changes in
load. In a standard AC induction motor, the shaft speed decreases as load increases, and increases
as load decreases. By increasing or decreasing the output frequency in response to an increasing or
decreasing load, the slip is counteracted and speed is maintained. Most standard NEMA B motors
have a 3% slip rating.
P31-P37 PRESET SPEED #1 - #7
Preset speeds are activated by contact closures between TB-2 and TB-13A, 13B, and 13C. The TB-13
terminals must be programmed as preset speed selects using Parameters 10-12.
NOTE
• Preset speeds can operate below the frequency defined by the minimum frequency
parameter (Parameter 23). The range of adjustment for the preset speeds is from 0
Hz to the maximum frequency (Parameter 24).
• When a TB-13 terminal is programmed for a function other than a preset speed
select, it is considered OPEN for the table above.
Refer to the table below for activation of the preset speeds using the TB-13 terminals.
SPEED #
TB - 13A
TB - 13B
TB - 13C
1
CLOSED
OPEN
OPEN
2
OPEN
CLOSED
OPEN
3
OPEN
OPEN
CLOSED
4
CLOSED
CLOSED
OPEN
5
CLOSED
OPEN
CLOSED
6
OPEN
CLOSED
CLOSED
7
CLOSED
CLOSED
CLOSED
Preset Speed #6 and #7 can also be used as skip frequencies to restrict the drive from operating at
frequencies that cause vibration in the system as described in Parameter 38.