Campbell 109 User Guide

Model 109 Temperature Probe

Revision: 12/10

Copyright © 1983-2010

Campbell Scientific, Inc.

Warranty and Assistance

The MODEL 109 TEMPERATURE PROBE is warranted by Campbell
Scientific, Inc. to be free from defects in materials and workmanship under
normal use and service for twelve (12) 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. The following
contact information is for US and International customers residing in countries
served by Campbell Scientific, Inc. directly. Affiliate companies handle
repairs for customers within their territories. Please visit
www.campbellsci.com to determine which Campbell Scientific company
serves your country.

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

For all returns, the customer must fill out a “Declaration of Hazardous Material
and Decontamination” form and comply with the requirements specified in it.
The form is available from our website at
completed form must be either emailed to [e-mail]
435-750-9579. Campbell Scientific will not process any returns until we
receive this form. If the form is not received within three days of product
receipt or is incomplete, the product will be returned to the customer at the
customer’s expense. Campbell Scientific reserves the right to refuse service on
products that were exposed to contaminants that may cause health or safety
concerns for our employees.

www.campbellsci.com/repair

. A

or faxed to

109 Table of Contents

PDF viewers note: These page numbers refer to the printed version of this document. Use
the Adobe Acrobat® bookmarks tab for links to specific sections.

1. General .........................................................................1

1.1 Specifications............................................................................................1

2. Accuracy.......................................................................2

3. Installation....................................................................3

3.1 Air Temperature........................................................................................3

3.1.1 Siting...............................................................................................3

3.1.2 Assembly and Mounting.................................................................3

3.2 Soil Temperature ......................................................................................5

3.3 Water Temperature...................................................................................5

4. Wiring............................................................................5

5. Programming ...............................................................6

5.1 CRBasic....................................................................................................6

5.1.1 CRBasic Examples..........................................................................6

5.1.1.1 Sample Program for CR200(X) Series Datalogger...............7

5.1.1.2 Sample Program for CR1000 Datalogger..............................7

5.2 Edlog.........................................................................................................8

5.2.1 Example Edlog Programs................................................................8

5.2.1.1 Example Program for CR10X...............................................8

5.3 Electrical Noisy Environments...............................................................10

5.4 Long Lead Lengths.................................................................................10

6. Measurement Details.................................................10

7. Maintenance and Calibration....................................11

8. Troubleshooting ........................................................12

Figures

2-1. Steinhart and Hart....................................................................................2

2-2. Possible Errors.........................................................................................3

3-1. 109 and 41303-5A Radiation Shield on a Tripod Mast...........................4

3-2. 109 and 41303-5A Radiation Shield on a CM200 Series Crossarm .......4

6-1. 109 Thermistor Probe Schematic............................................................9

i

109 Table of Contents

Tables

1-1. Recommended Cable Lengths................................................................ 1

4-1. Connections to Campbell Scientific Dataloggers................................... 5

5-1. Wiring for Example Programs................................................................ 6

5-2. Wiring for Example Programs................................................................ 8

ii

Model 109 Temperature Probe

1. General

The 109 probe uses a thermistor to measure temperature. It is designed for use
with the CR200(X) series datalogger, which has a special instruction, the
Therm109, for measuring it. The Therm109 instruction is also available for
the CR800, CR850, CR1000, and CR3000 dataloggers. The probe can be
measured with other Campbell Scientific dataloggers using generic
measurement instructions.

The 109 Temperature Probe can measure air/soil/water temperatures. For air
temperature, a 41303-5A radiation shield is used to mount the 109 probe and
limit solar radiation loading. The probe can be buried in soil or submerged in
water to 50 ft (21 psi).

The -L portion of the probe’s model number indicates that the cable length is
user specified. This manual refers to the sensor as the 109.

Cable length for the 109 is specified when the sensor is ordered. Table 1-1
gives the recommended cable length for mounting the sensor on a tripod or
tower.

TABLE 1-1. Recommended Cable Lengths

2 m Height Atop a tripod or tower via a 2 ft crossarm such as the CM202

Mast/Leg CM202 CM6 CM10 CM110 CM115 CM120 UT10 UT20 UT30

9 ft 11 ft 11 ft 14 ft 14 ft 19 ft 24 ft 14 ft 24 ft 37 ft

Note: Add two feet to the cable length if you are mounting the enclosure on the leg base of a light-weight tripod.

The 109 ships with:
(1) Resource CD

1.1 Specifications

Sensor: BetaTherm 10K3A1 Thermistor
Temperature

Measurement Range: -50° to +70°C
Thermistor Inter-

changeability Error: Typically <±0.2°C over 0° to 70°C; ±0.5 @ -50°C
Temperature

Survival Range: -50° to +100°C
Linearization Error: The Steinhart and Hart equation used to calculate

temperature is fit to the range of 0 to 70°C; maximum
error is 0.03°C at -50°C.

1

Model 109 Temperature Probe

NOTE

2. Accuracy

Time Constant
In Air: Between 30 and 60 seconds in a wind speed of 5 m s

-1

Maximum Lead Length: 1000 ft.

®

The black outer jacket of the cable is Santoprene

rubber. This
compound was chosen for its resistance to temperature extremes,
moisture, and UV degradation. However, this jacket will
support combustion in air. It is rated as slow burning when
tested according to U.L. 94 H.B. and will pass FMVSS302.
Local fire codes may preclude its use inside buildings.

The overall probe accuracy is a combination of the thermistor's interchangeability
specification and the accuracy of the bridge resistor. The Steinhart and Hart
equation used to calculate temperature has a negligible error (Figure 2-1). In a
"worst case" the errors add to an accuracy of ±0.6°C over the range of -50° to 70°C
and ±0.25°C over the range of -10°C to 70°C. The major error component is the
interchangeability specification of the thermistor. The bridge resistor has a 0.1%
tolerance with a 10 ppm temperature coefficient. Figure 2-2 shows the possible
worst case probe and measurement errors. Note that at temperature extremes the
possible error in the CR200(X) measurement may be greater than the error that
may exist in the probe.

Steinhart & Hart - Tabulated values

0.03

0.025

0.02

0.015

0.01

Error Degrees C

0.005

0

-50 -40 -30 -20 -10 0 10 20 30 40 50 60 70

-0.005

Temperature Degrees C

FIGURE 2-1. Steinhart and Hart

2

Model 109 Temperature Probe

Worst Case Errors in 109 Temperature Measurement

0.7

0.6

0.5

0.4

0.3

0.2

Possible Error Degrees C

0.1

0

-50 -40 -30 -20 -10 0 10 20 30 40 50 60 70

Thermistor Tolerance
CR200 Bridge Measurement Error (0.06% of reading+2.4 mV)
CR10X Bridge Measurement Error, CR200 Resolution (0.5 mV, 0.6 mV)

24.9 k Ohm Fixed Resistor Tolerance (0.1% + 10ppm/degC away from 25deg)

Temperature Degrees C

FIGURE 2-2. Possible Errors

3. Installation

3.1 Air Temperature

3.1.1 Siting

3.1.2 Assembly and Mounting

Sensors should be located over an open level area at least 9 m (EPA) in
diameter. The surface should be covered by short grass, or where grass does
not grow, the natural earth surface. Sensors should be located at a distance of
at least four times the height of any nearby obstruction, and at least 30 m
(EPA) from large paved areas. Sensors should be protected from thermal
radiation, and adequately ventilated.

Standard measurement heights:

1.5 m +/- 1.0 m (AASC)

1.25 – 2.0 m (WMO)

2.0 m (EPA)

2.0 m and 10.0 m temperature difference (EPA)

Tools Required:

• 1/2” open end wrench

• small screw driver provided with datalogger

• small Phillips screw driver

• UV resistant cable ties

• small pair of diagonal-cutting pliers

3

Model 109 Temperature Probe

The 109 must be housed inside a radiation shield when used in the field. The
41303-5A Radiation shield has a U-bolt for attaching the shield to tripod mast /
tower leg (Figure 3-1), or CM200 series crossarm (Figure 3-2). The radiation
shield ships with the U-bolt configured for attaching the shield to a vertical
pipe. Move the U-bolt to the other set of holes to attach the shield to a
crossarm.

41303-5A

109

Tripod Mast
or Tower Leg

41303-5A

FIGURE 3-1. 109 and 41303-5A Radiation Shield on a Tripod Mast

Tripod Mast
or Tower Leg

109

CM200 Series Crossarm

FIGURE 3-2. 109 and 41303-5A Radiation Shield on a

CM200 Series Crossarm

4

The 109 is held within the 41303-5A by a mounting clamp on the bottom plate
of the 41303-5A (Figure 3-2). Loosen the two mounting clamp screws, and
insert the sensor through the clamp and into the shield. Tighten the screws to
secure the sensor in the shield, and route the sensor cable to the instrument
enclosure. Secure the cable to the tripod/tower using cable ties.

3.2 Soil Temperature

The 109 is suitable for shallow burial only. It should be placed horizontally at
the desired depth to avoid thermal conduction from the surface to the
thermistor. Placement of the cable inside a rugged conduit may be advisable
for long cable runs, especially in locations subject to digging, mowing, traffic,
use of power tools, or lightning strikes.

3.3 Water Temperature

The 109 can be submerged to 50 feet. Please note that the 109 is not weighted.
Therefore, the installer should either add a weighting system or secure the
probe to a fixed or submerged object.

Model 109 Temperature Probe

4. Wiring

Connections to Campbell Scientific dataloggers are given in Table 4-1.
Temperature is measured with one Single-Ended input channel and a Voltage
Excitation channel. Multiple probes can be connected to the same excitation
channel (the number of probes per excitation channel is physically limited by
the number of lead wires that can be inserted into a single voltage excitation
terminal, approximately six).

TABLE 4-1. Connections to Campbell Scientific Dataloggers

Color

Black Volt Excite Switched

Red Signal Single-Ended

Purple Signal

Heat Shrink
Label

CR200(X)
CR800
CR3000
CR1000

Voltage
Excitation
(VX)

Input

CR510
CR500
CR10(X)

Switched
Voltage
Excitation

Single-Ended
Input

AG

CR5000
21X
CR7
CR23X

Switched
Voltage
Excitation
(VX)

Single-Ended
Input

Reference

Clear Shield

G

5

Model 109 Temperature Probe

5. Programming

NOTE

5.1 CRBasic

This section is for users who write their own datalogger
programs. A datalogger program to measure this sensor can be
generated using Campbell Scientific’s Short Cut Program
Builder software. You do not need to read this section to use
Short Cut.

The datalogger is programmed using either CRBasic or Edlog. Dataloggers
that use CRBasic include our CR200(X)-series, CR800, CR850, CR1000,
CR3000, CR5000, and CR9000(X); see Section 5.1. Dataloggers that use
Edlog include our CR510, CR10(X), CR23X, and CR7; refer to Section 5.2.
Short Cut, CRBasic, and Edlog are included in our LoggerNet, PC400, and
RTDAQ software.

If applicable, please read “Section 5.3—Electrical Noisy Environments” and
“Section 5.4—Long Lead Lengths” prior to programming your datalogger.
Measurement details are provided in Section 6.

In the CR200(X)-series, CR800, CR850, CR1000, and CR3000 dataloggers,
Instruction Therm109 is used to measure temperature. Therm109 provides
excitation, makes a single ended voltage measurement, and calculates
temperature.

The Therm109 instruction has the following form:

Therm109 (Dest, Repetitions, SE Chan, Ex Chan, Multiplier, Offset)

A multiplier of 1.0 and an offset of 0.0 yields temperature in Celsius. For
Fahrenheit, use a multiplier of 1.8 and an offset of 32. See Section 5.1.1 fo r
example programs.

The CR5000 and CR9000(X) use the BrHalf instruction to read the 109’s
resistance. The Steinhart-Hart equation is entered as an expression to convert
the resistance to degrees Celsius.

5.1.1 CRBasic Examples

TABLE 5-1. Wiring for Example Programs

Color

Black Excitation EX1 or VX1
Red Signal SE1
Purple Signal Ground
Clear Shield

Description

CR200(X)
CR1000

6

5.1.1.1 Sample Program for CR200(X) Series Datalogger

'CR200(X) Series Datalogger

‘This example program measures a single 109 Thermistor probe
‘once a second and stores the average temperature every 10 minutes.

‘Declare the variable for the temperature measurement

Public Air_Temp

‘Define a data table for 10 minute averages:

DataTable (AvgTemp,1,1000)
DataInterval (0,10,min)
Average (1,Air_Temp,0)
EndTable

BeginProg
Scan (1 ,sec)
‘Measure the temperature:
Therm109 (Air_Temp,1,1,Ex1,1.0,0)
Call the data table:
CallTable AvgTemp
NextScan
EndProg

Model 109 Temperature Probe

5.1.1.2 Sample Program for CR1000 Datalogger

'CR1000

'Declare Variables and Units

Public T109_C

Units T109_C=Deg C

'Define Data Tables

DataTable(Table1,True,-1)
DataInterval(0,10,Min,10)
Average(1,T109_C,FP2,False)
EndTable

'Main Program

BeginProg
Scan(1,Sec,1,0)

'Default Datalogger Battery Voltage measurement Batt_Volt:
'109 Temperature Probe measurement T109_C:

Therm109(T109_C,1,1,1,0,_60Hz,1.0,0.0)

'Call Data Tables and Store Data

CallTable(Table1)
NextScan
EndProg

7

Model 109 Temperature Probe

5.2 Edlog

5.2.1 Example Edlog Programs

In Edlog, Instruction 5 is typically used to measure the 109’s resistance.
Instruction 55 is used to apply the Steinhart and Hart equation. Instruction 55
does not allow entering the coefficients with scientific notation. In order to u se
this instruction with as much resolution as possible, the ln resistance term is
pre scaled by 10

3

, and the 3rd order coefficient (C) to be multiplied by 109 (see Section

by 10

5.2.1).

TABLE 5-2. Wiring for Example Programs

Color Description CR10X

Black Excitation E1
Red Signal SE1
Purple Signal Ground AG
Clear Shield G

-3

. This allows the first order coefficient (B) to be multiplied

5.2.1.1 Example Program for CR10X

;{CR10X}
;
*Table 1 Program
01: 1 Execution Interval (seconds)

1: AC Half Bridge (P5)
1: 1 Reps
2: 25 2500 mV 60 Hz Rejection Range
3: 1 SE Channel
4: 1 Excite all reps w/Exchan 1
5: 2500 mV Excitation
6: 1 Loc [ V_Vx ]
7: 1.0 Mult
8: 0.0 Offset

2: Z=1/X (P42)
1: 1 X Loc [ V_Vx ]
2: 2 Z Loc [ Vx_V ]

3: Z=X+F (P34)
1: 2 X Loc [ Vx_V ]
2: -1 F
3: 3 Z Loc [ Vx_V_1 ]

4: Z=X*F (P37)
1: 3 X Loc [ Vx_V_1 ]
2: 24900 F
3: 4 Z Loc [ Rtherm ]

8

5: Z=LN(X) (P40)
1: 4 X Loc [ Rtherm ]
2: 5 Z Loc [ lnRt ]

6: Z=X*F (P37)
1: 5 X Loc [ lnRt ]
2: .001 F
3: 6 Z Loc [ Scal_lnRt ]

7: Polynomial (P55)
1: 1 Reps
2: 6 X Loc [ Scal_lnRt ]
3: 7 F(X) Loc [ 1_Tk ]
4: .001129 C0
5: .234108 C1
6: 0.0 C2
7: 87.7547 C3
8: 0.0 C4
9: 0.0 C5

8: Z=1/X (P42)
1: 7 X Loc [ 1_Tk ]
2: 8 Z Loc [ Tk ]

9: Z=X+F (P34)
1: 8 X Loc [ Tk ]
2: -273.15 F
3: 9 Z Loc [ Air_Temp ]

10: If time is (P92)
1: 0 Minutes (Seconds --) into a
2: 10 Interval (same units as above)
3: 10 Set Output Flag High (Flag 0)

11: Real Time (P77)
1: 110 Day,Hour/Minute (midnight = 0000)

12: Average (P71)
1: 1 Reps
2: 9 Loc [ Air_Temp ]

*Table 2 Program
02: 0.0000 Execution Interval (seconds)

*Table 3 Subroutines

End Program

Model 109 Temperature Probe

9

Model 109 Temperature Probe

5.3 Electrical Noisy Environments

5.4 Long Lead Lengths

‘Therm109 ( Dest, Reps, SEChan, ExChan, SettlingTime, Integ, Mult, Offset )

Therm109(T109_C,1,1,1,20000,_60Hz,1.0,0.0)

AC power lines, pumps, and motors, can be the source of electrical noise. If
the 109 probe or datalogger is located in an electrically noisy environment, the
109 probe should be measured with the 60 Hz or 50 Hz integration option as
shown in Examples 2 and 3. The 60 Hz and 50 Hz integration options are not
available for the CR200(X).

Additional settling time may be required for lead lengths longer than 300 feet,
where settling time is the delay before the measurement is made.

For the CR800, CR850, CR1000, and CR3000, the 60 Hz and 50 Hz
integration options include a 3 ms settling time; longer settling times can be
entered into the Settling Time parameter. The 60 Hz and 50 Hz integration
options as well as the Settling Time parameter are not available for the
CR200(X). The example Therm109 instruction listed below has a 20 mSec
(20000 µSec) delay:

In Edlog, use the DC Half Bridge instruction (P4) with a 20 millisecond delay
as shown below. Use P4 in place of P5 in Example 3 (the instructions that
follow P5 to convert the measurement result to temperature are still required).

1: Excite-Delay (SE) (P4)
1: 1 Reps
2: 25 2500 mV 60 Hz Rejection Range (Delay must be zero)
3: 1 SE Channel
4: 1 Excite all reps w/Exchan 1
5: 2 Delay (0.01 sec units)
6: 2500 mV Excitation
7: 3 Loc [V_Vx ]
8: .0004 Multiplier
9: 0.0 Offset

6. Measurement Details

Understanding the details in this section are not necessary for general
operation of the 109 Probe with CSI's dataloggers.

The Therm109 Instruction outputs a 2500 mV excitation and measures the
voltage across the 24.9 K resistor (Figure 6-1). The thermistor resistance
changes with temperature.

10

EX

Ω

HI

Model 109 Temperature Probe

BLACK

10K3AI

THERMISTOR

RED

AG

G

PURPLE
CLEAR

24.9K

FIGURE 6-1. 109 Thermistor Probe Schematic

The measured voltage, V, is:

=

EX

900,24

Where V
resistor and R

The resistance of the thermistor is:

R

t

is the excitation voltage, 24,900 ohms is the resistance of the fixed

EX

is the resistance of the thermistor

t

⎛
⎜

⎝

The Steinhart and Hart equation is used to calculate temperature from
Resistance:

, 0.1%

900,24

V

V

EX

RVV+

t

⎞

−= 1900,24

⎟
⎠

-3

-4

-8

1

RCRBA

TT

T++=

K

Where T
used in the Therm109 instruction are:

A = 1.129241x10
B = 2.341077x10
C = 8.775468x10

is the temperature in Kelvin. The Steinhart and Hart coefficients

K

7. Maintenance and Calibration

The 109 Probe requires minimal maintenance. Check monthly to make sure
the radiation shield is free from debris. Periodically check cabling for signs of
damage and possible moisture intrusion. For all factory repairs and
recalibrations, customers must get a returned material authorization (RMA).
Customers must also properly fill out a “Declaration of Hazardous Material

3

))(ln()ln(

11

Model 109 Temperature Probe

and Decontamination” form and comply with the requirements specified in it.
Refer to the “Warranty and Assistance” page for more information.

8. Troubleshooting

Symptom: Temperature is NAN, -INF, -9999, -273

Verify the red wire is connected to the correct Single-Ended analog input
channel as specified by the measurement instruction, the black wire is
connected to the switched excitation channel as specified by the measurement
instruction, and the purple wire is connected to datalogger ground.

Symptom: Incorrect Temperature

Verify the multiplier and offset parameters are correct for the desired units
(Section 5). Check the cable for signs of damage and possible moisture
intrusion.

NOTE

For all factory repairs, customers must get an RMA. Customers
must also properly fill out a “Declaration of Hazardous Material
and Decontamination” form and comply with the requirements
specified in it. Refer to the “Warranty and Assistance” page for
more information.

Symptom: Unstable Temperature

Try using the 60 Hz or 50 Hz integration op tions, and/or increasing the settling
time as described in Sections 5.3 and 5.4. Make sure the clear shield wire is
connected to datalogger ground, and the datalogger is properly grounded.

12

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UNITED STATES

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PO Box 444

Thuringowa Central

QLD 4812 AUSTRALIA

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Rua Luisa Crapsi Orsi, 15 Butantã

CEP: 005543-000 São Paulo SP BRAZIL

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11564 - 149th Street NW

Edmonton, Alberta T5M 1W7

CANADA

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300 N Cementerio, Edificio Breller

Santo Domingo, Heredia 40305

COSTA RICA

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UNITED KINGDOM

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Miniparc du Verger - Bat. H

1, rue de Terre Neuve - Les Ulis

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08024 Barcelona

SPAIN

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Please visit www.campbellsci.com to obtain contact information for your local US or International representative.