Campbell CR800 Series, Руководство оператора

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Section 5. Overview
72
Pulse Input Terminals and Measurements
Pulse Input
Terminal Input Type Data Option
CRBasic
Instruction
P Terminal
•
Low-level ac
•
High-
frequency
•
Switch-closure
• Counts
•
Frequency
•
Run
average of
frequency
PulseCount()
C Terminal
• Low-level ac
with LLAC4
(p.
562)
module
•
High-
frequency
•
Switch-closure
•
Counts
•
Frequency
• Running
average of
frequency
•
Interval
• Period
• State
PulseCount()
TimerIO()
5.2.3.3 Pulse Sensor Wiring
Read More See
Pulse Measurement Tips
(p. 377).
An example of a pulse sensor connection is illustrated in figure
Pulse Input
Wiring Example — Anemometer Switch
(p. 72).
Pulse sensors have two active
wires, one of which is ground. Connect the ground wire to a (signal ground)
terminal. Connect the other wire to a P terminal. Sometimes the sensor will
require power from the CR800, so there may be two added wires — one of which
will be power ground. Connect power ground to a G terminal. Do not confuse
the pulse wire with the positive power wire, or damage to the sensor or CR800
may result. Some switch closure sensors may require a pull-up resistor.
FIGURE 23: Pulse Input Wiring
Example — Anemometer