Campbell CR10 PROM, Руководство оператора

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SECTION 9. INPUT/OUTPUT INSTRUCTIONS
9-3
is dependent upon the sampling interval (e.g.,
speed, RPM), the value from the excessive
interval should be discarded. If the value is
discarded the value in the RAM buffer from the
previous measurement will be used.
There is also an option to output the count as a
frequency (i.e., counts/execution interval in
seconds = Hz) as well as discard the result
from an excessive interval. This allows the use
of a conversion factor that is independent of the
execution interval.
The options of discarding counts from long
intervals, pulse input type, and using a 16 bit
counter are selected by the code entered for
the 4th parameter (Table 9-2).
NOTE: All pulse count instructions must be
kept in the same table. If the Pulse Count
Instruction is contained within a subroutine,
that subroutine must be called from Table 2.
TABLE 9-2. Pulse Count Configuration
Codes
Code Configuration
0 High frequency pulse
1 Low level AC
2 Switch closure
3 High frequency pulse, sixteen
bit counter
4 Low level AC, sixteen bit
counter
1X Long interval data discarded
2X Long interval data discarded,
frequency (Hz) output
PARAM. DATA
NUMBER TYPE DESCRIPTION
01: 2 Repetitions
02: 2 Pulse channel number
for first measurement
03: 2 Configuration code
(from above table)
04: 4 Input location for first
measurement
05: FP Multiplier
06: FP Offset
Input locations altered: 1 per measurement
Intermediate storage locations altered: 1 for
each repetition
*** 4 EXCITE, DELAY, AND MEASURE ***
FUNCTION
This instruction is used to apply an excitation
voltage, delay a specified time, and then make
a single-ended voltage measurement. A 1
before the excitation channel number (1X)
causes the channel to be incremented with
each repetition.
PARAM. DATA
NUMBER TYPE DESCRIPTION
01: 2 Repetitions
02: 2 Range code (Table 9-1)
03: 2 Single-ended channel
number for first
measurement
04: 2 Excitation channel
number
05: 4 Delay in hundredths of
a second
06: 4 Excitation voltage
(millivolts)
07: 4 Input location number
for first measurement
08: FP Multiplier
09: FP Offset
Input locations altered: 1 per measurement
*** 5 AC HALF BRIDGE ***
FUNCTION
This instruction is used to apply an excitation
voltage to a half bridge (Figure 13.5-1), make a
single-ended voltage measurement of the
bridge output, reverse the excitation voltage,
then repeat the measurement. The difference
between the two measurements is used to
calculate the resulting value which is the ratio of
the measurement to the excitation voltage. A 1
before the excitation channel number (1X)
causes the channel to be incremented with
each repetition.
The excitation "on time" for each polarity is
exactly the same to insure that ionic sensors do
not polarize with repetitive measurements. The
range should be selected to be a fast
measurement (range 11-15), limiting the
excitation on time to less than 800
microseconds at each polarity. A slow
integration time should not be used with ionic
sensors because of polarization error.