Campbell Scientific CR10 CR10 Measurement and Control - Page 104

Coeff. Value, Y3 102779.1

Get Campbell Scientific CR10 PDF manuals and user guides View all Campbell Scientific CR10 manuals
Add to My Manuals
Save this manual to your list of manuals

Page 104 highlights

SECTION 7. MEASUREMENT PROGRAMMING EXAMPLES Time out calculations using a recommended 9000 and 5000 cycles for temperature and pressure at the maximum frequency are shown below. Time out for temperature: 6, 5.22 = (5.8.1 0-q(9000/0.01 ) Time out for pressure: 16, 1 5.5 = (3.1.1 0-sX5000/0.01 ) lf the time out expires before the requested number of cycles are read, -99999" is stored in the input location (Parameter 6). After reading the correct number of cycles, program execution advances to the next instruction;the time out may be over estimated without losing execution speed. CONVERTING MICROSECONDS TO'C AND PSI The temperature and pressure in microseconds are converted to'C and psi according to the following relationships provided by Paroscientific. CPr*es(s'lurTeo(zpnsai)u=2). (1 (D. (1 - tozffaul;; Temperature ("C) - Y.,U + Y2U2 + Y3U3 where, C = Cr + C2U + C3U2 (psi), To = Tr + T2U + T3U2 + TaU3 + T5Ua (microsecond), D = Dr + D2U (microsecond), U = U(t) Us (microsecond), Tau = measured pressure (microsecond), U(t) = n'1g..ured temperature (microsecond). Values for the calibration coefficients (Uo, Yt, Y2, Y3, C1,C2, C3, D1, D2,T1,T2,Tg, Ta, T5) are provided by Paroscientific. ENTERING THE COEFFICIENTS Coetficients are entered using CR10 Instruction 30 or 64. A calibration sheet from Paroscientific which accompanies the transducer lists the 14 coefficients. TableT.'17-3 shows the correct format for entering the coefficients. The coetficients shown are for transducer Serial Number 30135. Your coefficients will be ditferent. TABLE 7.17-g Goefficient Entry Format for Paroscientilic "T" Series Pressure Transducer Instruction 30 Coeff. Value Param.l uo Y1 -3957.08.6340825-339705..38603 Y2' -7114.265 -7114.3 Y3 102779.1 ',t02.78 0.0 0.0 0.0 3.0* c1 70.29398 70.294 0.0 c2 ca -1169.6.21806174-11196..261901 Dl D2 TT12 0.0308837 0.0 30.884 0.0 26.33703 26.337 0.8516985 0.85170 0.0 0.0 -3.0* 0.0 0.0 0.0 T3 21.80118 21.801 0.0 T4 0.0 T5 0.0 0.0 0.0 0.0 0.0 "Ysand D1 are the only coefficients with a nonzero Only the first 5 digits of each 7 digit coefficient are entered in the datalogger. The maximum error that occurs due to using five digit coefficients is 0.001 psi throughout a 15 psi range at any temperature between -30 and +60"C. The maximum error in temperature calculations is 0.2oC over the same range. CONNECTIONS Figure 7.17-l details the components required for connecting the transducer to the CR10. The user supplied components are commonly available at commercial electronic stores. PROGRAM EXAMPLE The program may be divided into the following 7 steps. 1. Load the coefficients into input locations (Subroutine 1). 2. Measure the temperature and pressure. 3. Compute U. 4. Compute temperature, oC. 5. Compute Ts, T92, Tau2, and 1-Tozn^uz. 6. Compute D. 7. Compute C. 8. Compute pressure (psi.) 7-20

  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10
  • 11
  • 12
  • 13
  • 14
  • 15
  • 16
  • 17
  • 18
  • 19
  • 20
  • 21
  • 22
  • 23
  • 24
  • 25
  • 26
  • 27
  • 28
  • 29
  • 30
  • 31
  • 32
  • 33
  • 34
  • 35
  • 36
  • 37
  • 38
  • 39
  • 40
  • 41
  • 42
  • 43
  • 44
  • 45
  • 46
  • 47
  • 48
  • 49
  • 50
  • 51
  • 52
  • 53
  • 54
  • 55
  • 56
  • 57
  • 58
  • 59
  • 60
  • 61
  • 62
  • 63
  • 64
  • 65
  • 66
  • 67
  • 68
  • 69
  • 70
  • 71
  • 72
  • 73
  • 74
  • 75
  • 76
  • 77
  • 78
  • 79
  • 80
  • 81
  • 82
  • 83
  • 84
  • 85
  • 86
  • 87
  • 88
  • 89
  • 90
  • 91
  • 92
  • 93
  • 94
  • 95
  • 96
  • 97
  • 98
  • 99
  • 100
  • 101
  • 102
  • 103
  • 104
  • 105
  • 106
  • 107
  • 108
  • 109
  • 110
  • 111
  • 112
  • 113
  • 114
  • 115
  • 116
  • 117
  • 118
  • 119
  • 120
  • 121
  • 122
  • 123
  • 124
  • 125
  • 126
  • 127
  • 128
  • 129
  • 130
  • 131
  • 132
  • 133
  • 134
  • 135
  • 136
  • 137
  • 138
  • 139
  • 140
  • 141
  • 142
  • 143
  • 144
  • 145
  • 146
  • 147
  • 148
  • 149
  • 150
  • 151
  • 152
  • 153
  • 154
  • 155
  • 156
  • 157
  • 158
  • 159
  • 160
  • 161
  • 162
  • 163
  • 164
  • 165
  • 166
  • 167
  • 168
  • 169
  • 170
  • 171
  • 172
  • 173
  • 174
  • 175
  • 176
  • 177
  • 178
  • 179
  • 180
  • 181
  • 182
  • 183
  • 184
  • 185
  • 186
  • 187
  • 188
  • 189
  • 190
  • 191
  • 192
  • 193
  • 194
  • 195
  • 196
  • 197
  • 198
  • 199
  • 200
  • 201
  • 202
  • 203
  • 204
  • 205
  • 206
  • 207
  • 208
  • 209
  • 210
  • 211
  • 212
  • 213
  • 214
  • 215
  • 216
  • 217
  • 218
  • 219
  • 220
  • 221
  • 222
  • 223
  • 224
  • 225
  • 226
  • 227
  • 228
  • 229
  • 230
  • 231
  • 232
  • 233
  • 234
  • 235
  • 236
  • 237
  • 238
SECTION
7.
MEASUREMENT
PROGRAMMING
EXAMPLES
Time out
calculations
using
a
recommended
9000 and 5000 cycles for temperature and
pressure at
the
maximum frequency are shown
below.
Time
out for
temperature:
6,
5.22
=
(5.8.1
0-q(9000/0.01
)
Time out
for
pressure:
16,
1
5.5
=
(3.1.1 0-sX5000/0.01
)
lf
the time out
expires
before
the
requested
number
of
cycles
are
read,
-99999" is
stored
in
the
input location (Parameter
6).
After
reading
the
correct
number of
cycles,
program
execution advances to
the
next
instruction;the
time
out
may be over estimated
without
losing
execution speed.
CONVERTING MICROSECONDS
TO'C
AND
PSI
The
temperature
and pressure
in
microseconds
are converted
to'C
and
psi according to
the
following
relationships provided by
Paroscientific.
Pressure (psi)
=
C*
('l
Toznau2).
(1 (D.
(1
-
tozffaul;;
Temperature
("C)
-
Y.,U + Y2U2 + Y3U3
where, C
=
Cr +
C2U
+
C3U2
(psi),
To
=
Tr
+
T2U
+ T3U2 + TaU3 + T5Ua
(microsecond),
D
=
Dr +
D2U
(microsecond),
U
=
U(t)
Us
(microsecond),
Tau
=
measured pressure (microsecond),
U(t)
=
n'1g..ured
temperature
(microsecond).
Values for the calibration coefficients
(Uo,
Yt,
Y2,
Y3, C1,C2, C3,
D1,
D2,T1,T2,Tg,
Ta,
T5)
are provided by Paroscientific.
ENTERING
THE
COEFFICIENTS
Coetficients are
entered
using
CR10
Instruction
30 or
64.
A calibration sheet
from
Paroscientific
which accompanies the
transducer
lists
the
14
coefficients. TableT.'17-3
shows the correct
format for entering the
coefficients. The
coetficients shown are for transducer Serial
Number
30135.
Your coefficients
will
be
ditferent.
TABLE
7.17-g Goefficient Entry
Format
for
Paroscientilic "T" Series Pressure
Transducer Instruction
30
Coeff. Value
Param.l
uo
5.860253
5.8603
Y1
-3970.348
-3970.3
Y2'
-7114.265
-7114.3
Y3 102779.1
',t02.78
c1
70.29398
70.294
c2
6.610141
6.6101
ca
-119.2867
-119.29
Dl
0.0308837
30.884
D2
0.0
0.0
T1
26.33703
26.337
T2
0.8516985
0.85170
T3
21.80118
21.801
T4
0.0
0.0
T5
0.0
0.0
0.0
0.0
0.0
3.0*
0.0
0.0
0.0
-3.0*
0.0
0.0
0.0
0.0
0.0
0.0
"Ysand
D1
are
the only coefficients with a non-
zero
Only the
first
5
digits of each 7 digit coefficient
are
entered
in
the datalogger. The
maximum
error that occurs due
to
using five digit
coefficients is 0.001 psi
throughout a
15 psi
range at any temperature between -30 and
+60"C.
The
maximum
error
in
temperature
calculations
is 0.2oC
over
the
same
range.
CONNECTIONS
Figure
7.17-l
details the
components
required
for connecting the transducer to
the
CR10.
The
user supplied components are commonly
available
at
commercial electronic stores.
PROGRAM EXAMPLE
The
program may be divided
into
the following
7
steps.
1.
Load the coefficients into input locations
(Subroutine
1).
2.
Measure the temperature and pressure.
3.
Compute
U.
4.
Compute
temperature,
oC.
5.
Compute Ts,
T92,
Tau2,
and 1-Tozn^uz.
6.
Compute
D.
7.
Compute
C.
8.
Compute pressure (psi.)
7-20