GE Industrial Solutions DV-300 DC Drive Users Manual - Manual (Page 183)

DV-300 Adjustable Speed Drives
——— FUNCTION DESCRIPTION ———
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Face value num Numerator of the face value factor
Face value den Denominator of the face value factor
The reference value given multiplied with the dimension factor and the face value factor defines the motor speed in rpm
Dimension factor
User
defined variable
X
Face value factor
X
Control variable Dim factor num
1
Dim factor den
1
Dim factor text
rpm
Face value num
1
Face value den
1
Figure 6.11.6.1: Calculation using dimension and face value factors
Example 1 of the calculation of the dimension factor
The drive speed is given in m/s. The conversion ratio is 0.01 m per revolution of the motor (Note: face value
factor = 1).
The dimension factor is calculated from
Dimension factor =
output (rpm)
input (here: m/s)
for01
0.01 m corresponds to 1 revolution of hte motor shaft
0.01 m/min corresponds to 1/min
0.01 m/60s corresponds to 1/min
Dimension factor =
for02
1
=
min
60 s
0.01 m
6000
1
s
m
1
min
When calculating the dimension factor, units should not be shortened (1 min is not shortened as 60 s)
Dim factor num
6000
Dim factor den 1
Dim factor text m/s
Example 2 of the calculation of the dimension factor
The reference values for a bottling plant are given in bottles per minute. One revolution of the drive corresponds
to the filling of 0.75 bottles. This corresponds to a dimension factor of 4/3. The speed limitation and the ramp
function are also given in bottles per minute
Dimension factor =
for03
output (rpm)
input (here: bottles / min)
3/4 of a bottle corresponds to 1 revolution of the motor shaft
Dimension factor =
for04
1
=
min
4 min
3 bottles
4
3
min
bottles
1
min
Units should not be shortened when calculating the dimension factor.