Honeywell SMV 3000 - Manual (Page 69)

1/99 SMV 3000 Transmitter User’s Manual 57
6.6 DPConf Configuration - PV1,
Continued
About Square Root
Output, continued Example: If you have an application with a differential pressure range of
0 to 100 inches of water with an input of 49 inches of water,
substituting into the above formulas yields:
49
100
• 100 = 49%
49%
100
• 100 = 70% Flow, and
70% • 16 + 4 = 15.2 mA dc Output
Square Root Dropout To avoid unstable output at PV1 readings near zero, the SMV 3000
transmitter automatically drops square root conformity and changes to
linear conformity for low differential pressure readings. As shown in
Figure 21, the square root dropout point is between 0.4 and 0.5 % of
differential pressure input.
Figure 21 Square Root Dropout Points for PV1
0 0.2 0.4 0.8 1 0.6 1.2 1.4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
0
Differential Pressure (% Full Scale)
Flow
(% Full
Scale)
0utput
(mA dc)
4
4.8
5.6
6.4
Dropout Points
22508
Sq
ua
re
R
oo
t C
ur
ve
Continued on next page