Allen-Bradley 22C-B012N103, Руководство пользователя

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Rockwell Automation Publication 22C-UM001J-EN-E - January 2017 161
Application Notes Appendix D
Analog PID Reference Signals
Parameters T070 [Analog In 1 Lo], T071 [Analog In 1 Hi], T074 [Analog In 2
Lo], and T075 [Analog In 2 Hi] are used to scale or invert an analog PID
Reference.
Examples
Scale Function
For a 0...5 volt signal, the following parameter settings are used so that a 0 volt
signal = 0% PID Reference and a 5 volt signal = 100% PID Reference.
• T069 [Analog In 1 Sel] or T073 [Analog In 2 Sel] = 2 “Voltage Mode -
Unipolar”
• T070 [Analog In 1 Lo] or T074 [Analog In 2 Lo] = 0.0%
• T071 [Analog In 1 Hi] or T075 [Analog In 2 Hi] = 50.0%
• A152 [PID Ref Sel] = 0 “0-10V Input”
Invert Function
For a 4...20 mA signal, the following parameter settings are used so that a
20 mA signal = 0% PID Reference and a 4 mA signal = 100% PID Reference.
• T069 [Analog In 1 Sel] or T073 [Analog In 2 Sel] = 1 “Current Mode
4-20 mA”
• T070 [Analog In 1 Lo] or T074 [Analog In 2 Lo] = 100.0%
• T071 [Analog In 1 Hi] or T075 [Analog In 2 Hi] = 0.0%
• A152 [PID Ref Sel] = 2 “Analog In 1” or 3 “Analog In 2”
0 10 20 3 0 40 50 60 70 8 0 90 100
PID Reference (%)
Input V
olts
2
4
6
8
10
12
0 10 20 30 40 50 60 70 80 90 100
PID Reference (%)
4-20mA Input
4
8
12
16
20
24