Campbell CR7 User manual

CR7 MEASUREMENT AND CONTROL SYSTEM
INSTRUCTION MANUAL
REVISION: 7/97
COPYRIGHT (c) 1991-1997 CAMPBELL SCIENTIFIC, INC.

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WARRANTY AND ASSISTANCE
The CR7 MEASUREMENT AND CONTROL SYSTEM is warranted by CAMPBELL SCIENTIFIC, INC. to
be free from defects in materials and workmanship under normal use and service for thirty-six (36)
months from date of shipment unless specified otherwise. Batteries have no warranty. CAMPBELL
SCIENTIFIC, INC.'s obligation under this warranty is limited to repairing or replacing (at CAMPBELL
SCIENTIFIC, INC.'s option) defective products. The customer shall assume all costs of removing,
reinstalling, and shipping defective products to CAMPBELL SCIENTIFIC, INC. CAMPBELL SCIENTIFIC,
INC. will return such products by surface carrier prepaid. This warranty shall not apply to any CAMPBELL
SCIENTIFIC, INC. products which have been subjected to modification, misuse, neglect, accidents of
nature, or shipping damage. This warranty is in lieu of all other warranties, expressed or implied, including
warranties of merchantability or fitness for a particular purpose. CAMPBELL SCIENTIFIC, INC. is not
liable for special, indirect, incidental, or consequential damages.
Products may not be returned without prior authorization. To obtain a Returned Materials Authorization
(RMA), contact CAMPBELL SCIENTIFIC, INC., phone [phone]. After an applications engineer
determines the nature of the problem, an RMA number will be issued. Please write this number clearly on
the outside of the shipping container. CAMPBELL SCIENTIFIC's shipping address is:
CAMPBELL SCIENTIFIC, INC.
RMA#_____
815 West 1800 North
Logan, Utah 84321-1784
CAMPBELL SCIENTIFIC, INC. does not accept collect calls.
Non-warranty products returned for repair should be accompanied by a purchase order to cover the repair.
815 W. 1800 N.
Logan, UT 84321-1784
USA
Phone [phone]
FAX [phone]
www.campbellsci.com
Campbell Scientific Canada Corp.
11564 -149th Street
Edmonton, Alberta T5M 1W7
CANADA
Phone [phone]
FAX [phone]
Campbell Scientific Ltd.
Campbell Park
80 Hathern Road
Shepshed, Loughborough
LE12 9GX, U.K.
Phone [phone]
FAX [phone]

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i
CR7 OPERATOR'S MANUAL
TABLE OF CONTENTS
PAGE
WARRANTY AND ASSISTANCE
SELECTED OPERATING DETAILS..............................................................................................v
CAUTIONARY NOTES......................................................................................................................vi
OVERVIEW
OV1. PHYSICAL DESCRIPTION
OV1.1 700X Control Module .......................................................................................................... OV-1
OV1.2 720 I/O Module.................................................................................................................... OV-2
OV1.3 Enclosures and Connector Options .................................................................................... OV-2
OV2. MEMORY AND PROGRAMMING CONCEPTS
OV2.1 Internal Memory.................................................................................................................. OV-3
OV2.2 CR7 Instruction Types......................................................................................................... OV-6
OV2.3 Program Tables and the Execution and Output Intervals ................................................... OV-6
OV3. PROGRAMMING THE CR7
OV3.1 Functional Modes................................................................................................................ OV-8
OV3.2 Key Definition...................................................................................................................... OV-8
OV3.3 Programming Sequence ..................................................................................................... OV-8
OV3.4 Instruction Format............................................................................................................... OV-9
OV3.5 Entering a Program............................................................................................................. OV-9
OV4. PROGRAMMING EXAMPLE
OV4.1 Measurement.................................................................................................................... OV-10
OV4.2 Output ............................................................................................................................... OV-12
OV4.3 Editing an Existing Program.............................................................................................. OV-14
OV4.4 EDLOG Program Listing ................................................................................................... OV-14
OV5. DATA RETRIEVAL OPTIONS................................................................................ OV-15
OV6. SPECIFICATIONS...................................................................................................... OV-17

TABLE OF CONTENTS
ii
PROGRAMMING
1. FUNCTIONAL MODES
1.1 Program Tables - *1, *2, and *3 Modes ................................................................................. 1-1
1.2 Setting and Displaying the Clock - *5 Mode........................................................................... 1-2
1.3 Displaying and Altering Input Memory or Flags - *6 Mode..................................................... 1-2
1.4 Compiling and Logging Data - *0 Mode ................................................................................. 1-3
1.5 Memory Allocation - *A........................................................................................................... 1-4
1.6 Memory Testing and System Status - *B Mode ..................................................................... 1-5
1.7 *C Mode - Security................................................................................................................. 1-6
1.8 *D Mode - Save or Load Program.......................................................................................... 1-7
2. INTERNAL DATA STORAGE
2.1 Final Storage Areas, Output Arrays, and Memory Pointers................................................... 2-1
2.2 Data Output Format and Range Limits .................................................................................. 2-2
2.3 Displaying Stored Data on Keyboard/Display - *7 Mode........................................................ 2-3
3. INSTRUCTION SET BASICS
3.1 Parameter Data Types........................................................................................................... 3-1
3.2 Repetitions/Card Number....................................................................................................... 3-1
3.3 Entering Negative Numbers................................................................................................... 3-1
3.4 Indexing Input Locations ........................................................................................................ 3-2
3.5 Voltage Range and Overrange Detection .............................................................................. 3-2
3.6 Output Processing.................................................................................................................. 3-2
3.7 Use of Flags: Output and Program Control........................................................................... 3-3
3.8 Program Control Logical Constructions ................................................................................. 3-4
3.9 Instruction Memory and Execution Time................................................................................ 3-6
3.10 Error Codes............................................................................................................................ 3-9
DATA RETRIEVAL/COMMUNICATION
4. EXTERNAL STORAGE PERIPHERALS
4.1 On-Line Data Transfer - Instruction 96, *4 Mode................................................................... 4-1
4.2 Manually Initiated Data Output - *9 Modes............................................................................. 4-2
4.3 Storage Module...................................................................................................................... 4-3
4.4 Printer Output Formats........................................................................................................... 4-4
5. TELECOMMUNICATIONS
5.1 Telecommunications Commands .......................................................................................... 5-1
5.2 Remote Programming of the CR7.......................................................................................... 5-3
6. 9 PIN SERIAL INPUT/OUTPUT
6.1 Pin Description....................................................................................................................... 6-1
6.2 Enabling Peripherals.............................................................................................................. 6-2
6.3 Interrupting Data Transfer to Storage Peripherals................................................................. 6-2
6.4 Telecommunications - Modem Peripherals............................................................................ 6-2
6.5 Interfacing with Computers, Terminals, and Printers............................................................. 6-2

TABLE OF CONTENTS
iii
PROGRAMMING EXAMPLES
7. MEASUREMENT PROGRAMMING EXAMPLES
7.1 Single Ended Voltage-LI200S Silicon Pyranometer................................................................7-1
7.2 Differential Voltage Measurement...........................................................................................7-1
7.3 Thermocouple Temperatures Using 723-T Reference...........................................................7-2
7.4 Thermocouple Temperatures Using an External Reference Junction....................................7-2
7.5 Thermocouples for Differential Temperature Measurement...................................................7-3
7.6 Temperature with Calibrated Thermocouples.........................................................................7-4
7.7 107 Temperature Probe..........................................................................................................7-5
7.8 207 Temperature and RH Probe.............................................................................................7-5
7.9 Anemometer with Photochopper Output.................................................................................7-6
7.10 Tipping Bucket Raingage with Long Leads.............................................................................7-6
7.11 100 ohm PRT in 4 Wire Half-Bridge........................................................................................7-7
7.12 100 ohm PRT in 3 Wire Half-Bridge........................................................................................7-8
7.13 100 ohm PRT in 4 Wire Full-Bridge........................................................................................7-9
7.14 Pressure Transducer-4 Wire Full-Bridge ..............................................................................7-10
7.15 Lysimeter-6 Wire Load Cell...................................................................................................7-11
7.16 227 Gypsum Soil Moisture Block ..........................................................................................7-13
7.17 Nonlinear Thermistor in Half Bridge (CSI Model 101)...........................................................7-14
8. PROCESSING AND PROGRAM CONTROL EXAMPLES
8.1 Computation of Running Average...........................................................................................8-1
8.2 Rainfall Intensity......................................................................................................................8-2
8.3 SUB 1 Minute Output Interval Synched to Real Time.............................................................8-3
8.4 Analog Output to Strip Chart...................................................................................................8-4
8.5 Converting 0-360 Wind Direction Output to 0-540 for Strip Chart...........................................8-5
8.6 Covariance Correlation Programming Example......................................................................8-6
INSTRUCTIONS
9. INPUT/OUTPUT INSTRUCTIONS.....................................................................................9-1
10. PROCESSING INSTRUCTIONS......................................................................................10-1
11. OUTPUT PROCESSING INSTRUCTIONS...................................................................11-1
12. PROGRAM CONTROL INSTRUCTIONS......................................................................12-1
MEASUREMENTS
13. CR7 MEASUREMENTS
13.1 Fast and Slow Measurement Sequence...............................................................................13-1
13.2 Single-Ended and Differential Voltage Measurements .........................................................13-1
13.3 The Effect of Sensor Lead Length on the Signal Settling Time............................................13-3
13.4 Thermocouple Measurements............................................................................................13-11
13.5 Bridge Resistance Measurements......................................................................................13-15
13.6 Resistance Measurements Requiring AC Excitation ..........................................................13-19
13.7 Pulse Count Measurements................................................................................................13-20

TABLE OF CONTENTS
iv
INSTALLATION
14. INSTALLATION
14.1 Environmental Enclosure, Connectors and Junction Boxes ................................................ 14-1
14.2 System Power Requirements and Options.......................................................................... 14-2
14.3 Humidity Effects and Control................................................................................................ 14-5
14.4 Recommended Grounding Practices................................................................................... 14-5
14.5 Use of Digital Control Ports for Switching Relays ................................................................ 14-6
15. I/O CARD ADDRESSING AND MULTIPLE I/0 MODULES
15.1 I/O Card Identification Number Decoding ............................................................................ 15-1
15.2 Use of Multiple I/O Modules................................................................................................. 15-4
APPENDICES
A. GLOSSARY..............................................................................................................................A-1
B. CR7 PROM SIGNATURES FOR SYSTEMS EQUIPPED WITH
STANDARD SOFTWARE....................................................................................................B-1
C. BINARY TELECOMMUNICATIONS
C.1 Telecommunications Command With Binary Responses......................................................C-1
C.2 Final Storage Format .............................................................................................................C-3
C.3 Generation of Signature.........................................................................................................C-4
D. CALIBRATION PROCEDURES
D.1 Voltage Reference Calibration Procedure..............................................................................D-1
D.2 Clock Calibration Procedure ..................................................................................................D-2
LIST OF TABLES ..........................................................................................................................LT-1
LIST OF FIGURES........................................................................................................................LF-1
INDEX ................................................................................................................................................... I-1

v
SELECTED OPERATING DETAILS
The channel numbering on the Analog Input
Card refers to differential measurements. Single
ended measurements assume the HI and LO
side of each differential channel are two
independent single ended channels, e.g., the HI
and LO side of differential channel 2 are single
ended channels 3 and 4 respectively.
When multiple measurements are specified in
one measurement instruction (through use of
the "Repetitions Parameter") the CR7 I/O
Module is capable of sequencing through 500
fast, single-ended measurements per second.
This specification is the MEASUREMENT
SPEED and should not be confused with
throughput which is the rate at which
measurements are made, converted to
engineering units and stored in Final memory.
With the 700X Control Module (6303 CPU
board), the maximum throughput rate for fast,
single-ended measurements is approximately
310 measurements per second (1 second
execution: Instruction 1 entered 4 times, 3 times
with 99 repetitions, once with 11 repetitions).
Data is stored in Final Memory only by Output
Processing Instructions and only when the
Output Flag is set.
The default case for data stored in Final
Memory is low resolution (4 characters). High
resolution values (5 characters) must be
specified through use of Instruction 78. All data
contained in Input Memory is displayed (*6) as
HIGH RESOLUTION (5 characters) but the
default case for all data stored in Final Memory
is LOW RESOLUTION unless high resolution is
specified through use of Instruction 78.
Floating Point Format - The computations
performed in the CR7 use floating point
arithmetic. CSI's 4 byte floating point numbers
contain a 23 bit binary mantissa and a 6 bit
binary exponent. The largest and smallest
numbers that can be stored and processed are
9 x 1018 and 1 x 10-19, respectively.
The computations performed in the CR7 are
done in floating point arithmetic. Internally, the
number is stored and processed as a binary
number with a 23 bit binary mantissa and a 6 bit
binary exponent. The largest and smallest
numbers that can be stored and processed are
9 x 1018 and 1 x 10-19 respectively. The size
of the mantissa limits the resolution of the
arithmetic to 1 part in 223 binary (1.3 x 109
decimal).
Time is stored with data in Final Memory only if
specifically requested through use of the Real
Time Instruction 77.
Data in Final Storage can be erased without
altering the program by using the *A Mode to
repartition memory. The simplest method is to
re-enter the current allocation for Input Storage
(32 locations is the default allocation). All
memory can be erased and the CR7 completely
reset by entering 1744 for the number of bytes
left in Program Memory.
On-line (as opposed to a manually initiated
dump) data transfer to peripherals (printer,
storage module, etc.) occurs only if enabled
through use of the *4 Mode or Instruction 96.
Data transfer to cassette tape is no longer
supported.

vi
CAUTIONARY NOTES
The typical current drain for the CR7 is
approximately 100 mA while executing and 8-10
mA quiescent. Do not allow the lead-acid
batteries (2.5 Ahr) to drop below 11.76 V as
irreversible battery damage may result.
An external battery connected to the I/O Module
+12V and ground terminals continues to power
the CR7 system even though the CR7 power
switch is off. Reverse polarity protection is NOT
provided on this connection so exercise
extreme care if connecting external power
supplies.
Damage will occur to the analog input channel
circuitry if voltages in excess of +16V are
applied for a sustained period.
A POTENTIALLY DANGEROUS situation can
result due to hydrogen gas build up if the CR7 is
housed in a gas tight enclosure and the internal
lead acid batteries are shorted or overcharged.
Hydrogen concentration levels may occur which
are capable of causing injury or equipment
damage if ignited.