Siemens LMV5 Quick Start Manual page 189

The goal of the standardization process is to find the pulses per minute,
and therefore blower RPM that corresponds to a 95% (19.5 mA) signal to the VSD.
Once the LMV52 detects the peak motor RPM associated with 19.5mA,
it linearly scales the motor RPM to the 4-19.5 mA signal.
More specifically for the standardization in Figure 7-2.1, it associates 4 mA with 0 RPM
and 19.5mA with 3544 RPM and performs a two-point linear interpolation.
If the standardization shown if Figure 7-2.1 were performed on a LMV52,
and parameter Num Puls per R is set to 3 for a three fingered speed wheel,
the LMV52 would automatically set parameter Standardized Sp to 3544 RPM.
Manual setting of the Standardized SP parameter is possible,but not recommended.
The useful result of standardization is a base line for LMV52 that is custom tailored to the
VSD / motor that is being used with the LMV52. This base line has three main components:
VSD Control %,
During normal operation, the LMV52 can increase or decrease the milliamp signal to the
VSD to maintain a certain RPM.
There are limits on how much correction the milliamp signal to the VSD can be altered,
off of the base line, in response to a RPM that is too low or too high.
Figure 7-2.2 illustrates the results of the typical standardization performed in Figure 7-2.1.
Figure 7-2.2 also shows the approximate corection limits of how much the VSD control's
output signal can be altered in response to a measured RPM that is too low or too high.
Figure 7-2.2 Results of Standardization, VSD Control Output Signal Variation
Results of Standardization
Standardized Standardized
VSD Control Blower Shaft
% RPM
10
15.0
20.0
25.0
30.0 1066
35.0 1244
40.0 1421
45.0 1599
50.0 1777
55.0 1954
60.0 2132
65.0 2310
70.0 2488
75.0 2665
80.0 2843
85.0 3021
90.0 3199
95.0 3376
100.0 3554
LMV5 QSG Rev 4
Blower Shaft RPM,
Standardized
Output mA
Signal to VSD
355 5.6
533 6.4
710 7.1
888 7.9
8.7
9.5
10.2
11.0
11.8
12.5
13.3
14.1
14.9
15.6
16.4
17.2
18.0
18.7
19.5
Sec 7 Pg 5
and Output mA signal to VSD.
Approximate Correction Limits
Maximum signal Minimum signal to
to correct for low correct for high
RPM (mA)
7.92
8.69
9.46
10.24
11.01
11.78
12.55
13.33
14.10
14.87
15.64
16.41
17.19
17.96
18.73
19.50
20.28
21.05
21.82
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RPM (mA)
4.05
4.82
5.59
6.37
7.14
7.91
8.68
9.46
10.23
11.00
11.77
12.54
13.32
14.09
14.86
15.63
16.41
17.18
17.95