Danfoss vlt AQUA Instruction Manual page 87

®
VLT AQUA Drive
Instruction Manual
3-10 Preset Reference
Array [8]
Range:
0.00 %* [-100.00 - 100.00 %]
3-41 Ramp 1 Ramp-up Time
Range:
10.00 s* [1.00 - 3600.00 s]
3-42 Ramp 1 Ramp-down Time
Range:
20.00 s* [1.00 - 3600.00 s]
3-84 Initial Ramp Time
Range:
0 s* [0–60 s]
Function:
Enter up to eight different preset references (0-7) in this parameter using array programming. The
preset reference is stated as a percentage of the value Ref
as a percentage of the other external references. If a Ref
Reference) is programmed, the preset reference is calculated as a percentage of the full reference
range, i.e., on the basis of the difference between Ref
to Ref . When using preset references, select Preset ref. bit 0 / 1 / 2 [16], [17] or [18] for the
MIN
corresponding digital inputs in parameter group 5.1* Digital Inputs.
Function:
Enter the ramp-up time, i.e., the acceleration time from 0 RPM to par. 1-25. Choose a ramp-up time
such that the output current does not exceed the current limit in par. 4-18 during ramping. See
Ramp 1 Ramp-down Time
ramp-down time in par.3-42
tacc nnorm par
×
par .3 − 41 =
ref rpm
See drawing above!
Function:
Enter the ramp-down time, i.e., the deceleration time from par.1-25
Choose a ramp-down time such that no overvoltage arises in the inverter due to regenerative op-
eration of the motor, and such that the generated current does not exceed the current limit set in
par. 4-18 Current Limit . See ramp-up time in par.3-41
tdec × nnorm par
par
.3 − 42 =
ref rpm
Function:
Enter the initial ramp-up time from zero speed to Motor Speed Low Limit, par. 4-11 or 4-12. Sub-
mersible deep well pumps can be damaged by running below minimum speed. A fast ramp time
below minimum pump speed is recommended. This parameter may be applied as a fast ramp rate
from zero speed to Motor Speed Low Limit.
®
MG.20.M5.22 - VLT is a registered Danfoss trademark
8 How to program the adjustable frequency
(par. 3-03 Maximum Reference) or
MAX
different from 0 (Par. 3-02 Minimum
MIN
and Ref . Afterwards, the value is added
MAX MIN
.
.1 − 25
s
Motor Nominal Speed
Ramp 1 Ramp-up Time
.1 − 25
s
drive
8
to 0 RPM.
.
8-17