Danfoss VLT AQUA Drive FC 202, Operating Instructions Manual

Page: 78 / 173

3-10 Preset Reference
Array [8]
Range: Function:
0.00 %* [-100.00 - 100.00 %] 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
MAX
(par. 3-03 Maximum Reference) or
as a percentage of the other external references. If a Ref
MIN
different from 0 (Par. 3-02 Minimum
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
MAX
and Ref
MIN
. Afterwards, the value is added
to Ref
MIN
. When using preset references, select Preset ref. bit 0 / 1 / 2 [16], [17] or [18] for the
corresponding digital inputs in parameter group 5.1* Digital Inputs.
3-41 Ramp 1 Ramp Up Time
Range: Function:
10.00 s* [1.00 - 3600.00 s] 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-down time in par. 3-42
Ramp 1 Ramp Down Time
.
par .3 − 41 =
tacc
×
nnorm par
.1 − 25
ref rpm
s
See drawing above!
3-42 Ramp 1 Ramp Down Time
Range: Function:
20.00 s* [1.00 - 3600.00 s] Enter the ramp-down time, i.e. the deceleration time from par. 1-25 Motor Nominal Speed to 0 RPM.
Choose a ramp-down time such that no over-voltage arises in the inverter due to regenerative
operation 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 Ramp 1 Ramp Up Time .
par .3 − 42 =
tdec × nnorm
par
.1 − 25
ref rpm
s
3-84 Initial Ramp Time
Range: Function:
0 s* [0 – 60 s] 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.
8. How to programme the frequency converter
VLT
®
AQUA Drive
Operating Instructions
78
MG.20.M5.02 - VLT ® is a registered Danfoss trademark
8