Campbell CR310 User Manual

Terminals SE1 and SE2 or C1 and C2 can be configured as digital pairs to monitor the two
channels of an encoder. The Quadrature() instruction can return:
l
The accumulated number of counts from channel A and channel B. Count will increase if
channel A leads channel B. Count will decrease if channel B leads channel A.
l
The net direction.
l
Number of counts in the A-leading-B direction.
l
Number of counts in the B-leading-A direction.
Counting modes:
l
Counting the increase on rising edge of channel A when channel A leads channel B.
Counting the decrease on falling edge of channel A when channel B leads channel A.
l
Counting the increase at each rising and falling edge of channel A when channel A leads
channel B. Counting the decrease at each rising and falling edge of channel A when
channel A leads channel B.
l
Counting the increase at each rising and falling edge of both channels when channel A
leads channel B. Counting the decrease at each rising and falling edge of both channels
when channel B leads channel A.
For more information, see Digital input/output specifications(p. 248).
18.5.5 Pulse measurement tips
The PulseCount() instruction uses dedicated 32-bit counters to accumulate all counts over
the programmed scan interval. The resolution of pulse counters is one count. Counters are read
at the beginning of each scan and then cleared. Counters will overflow if accumulated counts
exceed 4,294,967,296 (2
32
), resulting in erroneous measurements. See the CRBasic Editor help for
detailed instruction information and program examples:
https://help.campbellsci.com/crbasic/cr300/ .
Counts are the preferred PulseCount() output option when measuring the number of tips
from a tipping-bucket rain gage or the number of times a door opens. Many pulse-output
sensors, such as anemometers and flow meters, are calibrated in terms of frequency (Hz) so are
usually measured using the PulseCount() frequency-output option.
Use the LLAC4 module to convert non-TTL-level signals, including low-level AC signals, to TTL
levels for input to C terminals
Understanding the signal to be measured and compatible input terminals and CRBasic
instructions is helpful. See Pulse input terminals and the input types they can measure(p. 102).
18. Measurements106

Campbell CR310 Specifications

General

Brand	Campbell
Model	CR310
Category	Data Loggers
Language	English