Measurement and Control Module Operators Manual

SECTION 7. MEASUREMENT PROGRAMMING EXAMPLES
7-19
10: 0 Offset
04: P34 Z=X+F
01: 1 X Loc TEMP
02: -24 F
03: 3 Z Loc [:TEMP COMP]
05: P37 Z=X*F
01: 3 X Loc TEMP COMP
02: -.0698 F
03: 3 Z Loc [:TEMP COMP]
06: P33 Z=X+Y
01: 3 X Loc TEMP COMP
02: 2 Y Loc PRESSURE
03: 2 Z Loc [:PRESSURE ]
07: P89 If X<=>F
01: 5 X Loc CMPILE CK
02: 1 =
03: 0 F
04: 30 Then Do
08: P34 Z=X+F
01: 2 X Loc PRESSURE
02: 47.23 F
03: 4 Z Loc [:OFFSET ]
09: P30 Z=F
01: 1 F
02: 0 Exponent of 10
03: 5 Z Loc [:CMPILE CK]
10: P95 End
11: P35 Z=X-Y
01: 4 X Loc OFFSET
02: 2 Y Loc PRESSURE
03: 6 Z Loc [:DISTANCE ]
12: P End Table 1
7.17 PAROSCIENTIFIC "T" SERIES
PRESSURE TRANSDUCER
The Paroscientific "T" series transducer has
two resonating quartz crystals that output
frequency signals for temperature and
pressure. The pressure output requires
temperature compensation. Instruction 27
measures the outputs and returns period in
microseconds (refer to Table 7.17-1).
TABLE 7.17-1 Period Averaging Inst. 27
PARAM. DATA
NUMBER TYPE DESCRIPTION
01: 2 Repetitions
02: 2 Gain/output option
03: 2 Single Ended Input
Channel
04: 4 # Cycles to measure
05: 4 Time out (0.01 sec, at
least the maximum
duration of the # of cycles
specified + 1 1/2 cycles.)
06: 4 Destination input location
07: FP Multiplier
08: FP Offset
GAIN/OUTPUT OPTION, PARAMETER 2
The nominal pressure frequency range is 32 to
42 kHz over the stated pressure range (period
of 3.1*10
-5
to 2.4*10
-5
). The nominal
temperature frequency is 172 kHz, ±50 ppm/°C
(period of 5.8*10
-6
). The gain/output option
(Parameter 2) is based on the maximum input
frequency. For the stated temperature and
pressure frequency ranges, the gain codes are
3 and 4 (refer to Table 7.17-2). Codes 1 and 2
are not used with Paroscientific transducers.
For period, the output option is 0.
TABLE 7.17-2 Input Frequency Gain Codes
Range Peak to Peak Volts Maximum
Code Required @ Max. Freq.
* Frequency
12mV8kHz
23mV20kHz
3 12mV 50kHz
4 2 V 200 kHz
0x Output period in microseconds
1x
Output frequency in kHz
where x is range code
* AC voltage; must be centered around CR10
ground.
TIME OUT, PARAMETER 5
The "time out", Parameter 5, specifies the
maximum length of time the instruction waits on
each repetition to receive the number of cycles
specified in Parameter 4. The time out units
are 0.01 seconds. The minimum time out is the
time required to receive the specified number of
cycles at the maximum expected frequency.