Campbell Scientific CR10 CR10 Measurement and Control - Page 103

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

T

able

7

.17

-1).

SECTION

7.

MEASUREMENT PROGRAMMING EXAMPLES

TABLE 7.17-1 Period

Averaging

Inst.

27

PARAM.

DATA

NUMBER ryPE

DESCRIPTION

Repetitions

Gain/output option

Single Ended lnput

Channel

# Cycles

to

measure

Time out

(0.01 sec,

at

least

the

maximum

duration of the # of cycles

specified

+

1'll2cycles.)

Destination input location

Multiplier

Offset

GAIN/OUTPUT

OPTION,

PARAMETER

2

The

nominal pressure

frequency

range

is

32 to

42kHz overthe

stated

pressure range (period

of 3.1.10-5 to

2.4*10-s). The

nominal

temperature

frequency

is 172

kHz,

t50

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

Table7.17-2).

Codes

1

and

2

are

not used

with

Paroscientific transducers.

For period,

the

output option is

0.

TABLE 7.17-2

lnput

Frequency

Gain Codes

Range

Peak

to

Peak

Volts

Maximum

Code

Required

@

Max.

Freq.*

Frequency

0x

Output period

in

microseconds

1x

Output

frequency

in kHz

where x

is

range code

'AC

voltage;

must be centered around CR10

qround.

T]ME

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.

P34

1

-24

3

P37

3

o4:

01:

02:

03:

05:

01:

02:

03:

01:

02:

03:

o4:

05:

06:

07:

08:

4

FP

FP

06:

P33

01:

3

02:

2

03:

2

07:

P89

01:

5

02:.

1

03:

0

04:

30

11:

P35

01:

4

02:

2

03:

6

12:

P

Z=X+F

X Loc TEMP

F

Z

Loc

[:TEMP

COMP]

Z=X*F

X Loc

TEMP

COMP

F

Z

Loc

[:TEMP

COMP]

Z=X+Y

X Loc

TEMP

COMP

Y

LoC

PRESSURE

Z Loc

[:PRESSURE

]

lf X<=>F

X

Loc CMPILE CK

F

Then

Do

Z=X+F

X

Loc PRESSURE

F

Z

Loc

[:OFFSET

]

Z=F

F

Exponent

of

10

Z

Loc

[:CMPILE

CKI

End

Z=X'Y

X

Loc

OFFSET

Y

Loc PRESSURE

Z

Loc

[:DISTANCE ]

End

Table

1

-.0698

3

2

2

2

4

4

08:

01:

02:-

03:

09:

01:

02:

03:

10:

P34

2

47.23

4

P30

1

0

5

P95

1

2

3

4

8

kHz

20

kHz

50

kHz

200

kHz

2mV

3mV

12

mV

2V

7-19

Campbell Scientific CR10 CR10 Measurement and Control - Page 103

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