TheCS100 BAROMETRIC PRESSURE SENSOR 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 (435) 753-2342. 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 repair@campbellsci.com
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
CS100 Table of Contents
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2. CS100 as removed from the box and closeup of yellow warning label......4
3. Connector Key Attached to 5-pin Screw Terminal Plug Connector...........5
Tables
1. Signal and Ground Connectors for CS100 .................................................4
2. Conversion Factors for Alternative Pressure Units ....................................6
3. Multipliers and Offsets...............................................................................6
4. Wiring for Example Programs....................................................................7
i
CS100 Barometric Pressure Sensor
1. Introduction
The CS100 is a capacitive pressure transducer that uses the Setra's electrical
capacitor technology for barometric pressure measurements over the 600 to
1100 millibar range. The transducer’s compact and rugged polyester housing
with stainless blackplate contains two closely-spaced, parallel, electricallyisolated metallic surfaces. One of the surfaces is essentially a diaphragm
constructed of a Setra’s proprietary compound of fused glass and ceramic
(Setraceram™) or a low-hysteresis material, such as 17-4 PH SS. The
diaphragm is capable of detecting a slight change in the applied pressure,
which is then converted to an analog voltage signal by Setra’s custom
Application Specific Integrated Circuit (ASIC). The analog signal generated
by the barometer can be directly measured by a Campbell Scientific datalogger,
such as 21X, CR7, CR500, CR510, CR10(X), CR23X, CR200(X) series,
CR1000, CR3000, CR800, CR850, CR5000, and CR9000(X).
The CS100 is supplied in the triggered mode, in which the datalogger switches
12 VDC power to the barometer before the measurement. The datalogger then
powers down the barometer after the measurements to conserve power.
Other measurement range options such as 500 to 1100 millibar, an d 800 to
1100 millibar are also available. Please contact Campbell Scientific, Inc. for
ordering these special versions.
FIGURE 1. CS100 Barometric Pressure Sensor
1
CS100 Barometric Pressure Sensor
2. Specifications
2.1 Performance
2.1.1 Performance for “Standard” Range Option
Measurement Range: 600 mb to 1100 mb (hPa)
Operating Temperature Range: -40°C to +60°C (-40°F to +140°F)
Storage Temperature Range: -60°C to +120°C (-76°F to +248°F)
Proof Pressure: 1500 mb
Burst Pressure: 2000 mb
Humidity Range: non-condensing (up to 95% RH)
Media Compatibility: non-corrosive, non-condensing air or gas
Resolution: 0.01 mb
Total Accuracy
±1.0 mb @ 0°C to +40°C
±1.5 mb @ -20°C to +50°C
±2.0 mb @ -40°C to +60°C
Linearity: ±0.4 mb
Hysteresis: ±0.05 mb
Repeatability: ±0.03 mb
Long-term Stability: ±0.1 mb per year
1
: ±0.5 mb @ 20°C
2.1.2 Performance for “500 to 1100 mb” Range Option
Measurement Range: 500 to 1100 mb
Total Accuracy
±1.2 mb @ 0°C to +40°C
±2.0 mb @ -20°C to +50°C
±2.5 mb @ -40°C to +60°C
Linearity: ±0.5 mb
Hysteresis: ±0.06 mb
Repeatability: ±0.04 mb
2
: ±0.6 mb @ 20°C
2.1.3 Performance for “800 to 1100 mb” Range Option
Measurement Range: 800 to 1100 mb
Total Accuracy
±0.6 mb @ 0°C to +40°C
±1.0 mb @ -20°C to +50°C
±1.5 mb @ -40°C to +60°C
Linearity: ±0.25 mb
Hysteresis: ±0.03 mb
Repeatability: ±0.02 mb
1
The root sum squared (RSS) of end point non-l inearity, hysteresis, non-
repeatability and calibration uncertainty.
2
The root sum squared (RSS) of end point non-linearity, hysteresis, non-
repeatability and calibration uncertainty.
3
The root sum squared (RSS) of end point non-l inearity, hysteresis, non-
repeatability and calibration uncertainty.
3
: ±0.3 mb @ 20°C
2
2.2 Electrical
2.3 Physical
NOTE
CS100 Barometric Pressure Sensor
Supply Voltage: 9.5 V to 28 Vdc
Current Consumption: 3 mA nominal (operating mode)
1 µA quiescent (sleep mode)
Signal Output 0 to 2.5 Vdc
Warm-up Time: <1 second from shutdown mode
Response Time: <100 msec
Benefits: Calibration NIST traceable
Meets CE conformance standards
Dimensions (Main Box): 3.6” x 2.4” x 1.0” (9.1 x 6.1 x 2.5 cm)
Weight: 4.8 oz (135 g)
Mounting Hole Centers: 3 inches (7.62 cm)
Pressure Connector: 1/8” ID barbed fitting
®
The black outer jacket of the cable is Santoprene
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 building.
rubber. This
3. Installation
3.1 Venting and Condensation
CAUTION
NOTE
3.2 Mounting
To prevent condensation, install the sensor in an environmentally protected
enclosure, complete with desiccant, which should be changed at regular
intervals. As the sensor must detect the external ambient pressure the
enclosure must not be ‘hermetically sealed’.
Failure to protect the sensor from condensation may result
in permanent damage.
If it is necessary to make a vent hole on the outer wall of an
enclosure, do not make the hole on one of the vertical side walls,
as wind blowing around it can cause transient changes in
pressure.
The mounting holes for the sensor are one-inch-centered (three inches apart),
and will mount directly onto the holes on the backplates of the Campbell
Scientific enclosures. Mount the sensor with the pneumatic connector pointing
vertically downwards to prevent condensation collecting in the pressure cavity,
and also to ensure that water cannot enter the sensor.
3
CS100 Barometric Pressure Sensor
4. Wiring
4.1 Datalogger Connection
Before connecting the barometer to the datalogger, a yellow warning label
must be removed from the pigtails (see Figure 2). The warning label reminds
the user of the importance of properly connecting the barometer to the
datalogger. Proper wiring is shown in Table 1.
Yellow Warning Label
FIGURE 2. CS100 as Removed from the Box
TABLE 1. Signal and Ground Connectors for CS100
Wire
Blue VOUT S.E. Input High Side of Diff Input
Yellow AGND
Black GND
Green EXT TRIG
Red SUPPLY 12 VDC 12 VDC
Shield Shield
4
CS100 Terminal
Single-Ended Measurement
AG (CR10(X), CR500, CR510)
(Other Dataloggers)
(21X, CR7, CR9000(X))
G (Other Dataloggers)
Control port (use to turn power
on/off)
G (CR10(X), CR500, CR510)
(Other Dataloggers)
Datalogger
Datalogger
Differential Measurement
Low Side of Diff. Input
(21X, CR7, CR9000(X))
G (Other Dataloggers)
Control port (use to turn power
on/off)
G (CR10(X), CR500, CR510)
(Other Dataloggers)
CS100 Barometric Pressure Sensor
WARNING
Improper wiring may damage the CS100 beyond repair.
4.2 5-pin Screw Terminal Plug Connector
The datalogger connects to the CS100 via a 5-pin screw terminal plug
connector. This connector is removable and may be replaced. The
replacement connector may come with a connector key attached to it to ensure
that the connector is plugged into the CS100 right side up (see Figure 3).
When the connector is right side up, it will easily plug into the barometer.
WARNING
5. Programming
FIGURE 3. Connector Key Attached to
5-pin Screw Terminal Plug Connector
A 5-pin screw terminal that is plugged in upside down
will damage the sensor—perhaps beyond repair.
The CS100 sensor is measured using the singled-ended voltage measurement
instruction.
Atmospheric pressure changes little with time. In most weather station
applications measuring pressure once an hour is adequate.
Program Example 1 is for the dataloggers that use the CRBasic language, such
as CR200(X), CR800, CR850, CR1000, CR3000, CR5000, and CR9000(X).
In the example, the CR1000 measures the CS100 once an hour in a program
that runs at 1 Hz. In order to keep the CR1000 running in a pipeline mode, the
measurement instruction is placed outside the “If” statement. The
measurement is made every scan, and the measured value is first written into a
temporary variable called "CS100_temp". Once the CS100 is turned on one
minute before the hour, the CS100 starts to make the correct pressure
measurements. At the top of the hour, the correct value is copied into the
current variable called "pressure", and the sensor is turned off immediately.
5
CS100 Barometric Pressure Sensor
In Program Example 2, the CR10X datalogger (Edlog datalogger) turns on the
CS100 one minute before the top of the hour using a control port. On the hour
the datalogger measures the CS100, and then it turns the CS100 off.
5.1 Conversion Factors
In the example programs, the pressure is reported in millibars (mb). To report
pressure in different units, multiply the measured pressure by the appropriate
conversion factor using the P37 (Z=X*F) instruction for CR500, CR510,
CR10(X), CR23X, 21X, and CR7, or by adding an expression for CR200(X),
C800, CR850, CR1000, CR3000, CR5000, and CR9000(X) dataloggers. See
Table 2 below for conversion factors.
To Find Multiply by
hPa 1.0
kPa 0.1
mm of Hg 0.75006
in of Hg 0.02953
Psi 0.0145
Atm 0.00099
Torr 0.75006
TABLE 2. Conversion Factors for
Alternative Pressure Units
5.2 Multipliers and Offsets for Different Measurement Range
Options
For CS100 barometric pressure transducers with measurement range options
other than the standard 600 to 1100 mb option, please refer to the table below
for proper multipliers and offsets.
TABLE 3. Multipliers and Offsets
Range Options Multiplier Offset
600 to 1100 mb
(Standard range)
500 to 1100 mb 0.24 500
800 to 1100 mb 0.12 800
0.2 600
6
CS100 Barometric Pressure Sensor
5.3 Program Examples
The CS100 wiring instructions for the example programs are shown in Table 4
below.
TABLE 4. Wiring for Example Programs
Wire Color Description CR10(X) CR1000
Blue VOUT – Pressure Signal Out SE6 SE15
Red SUPPLY – 12 Vdc Power In 12V 12V
Black GND – Power Ground G G
Yellow AGND – Signal Ground AG
Green ETX. TRIG. – External Trigger C8 C4
Clear Shield G G
Example 1. Sample Program for CR1000 (CRBasic) Datalogger
'CR1000 Datalogger
Public CS100_temp
Public pressure
Units pressure = mbar
If (IfTime (59,60,min)) Then WriteIO (&b1000, &b1 00 0 )
‘Copy the correct value to a current variable called “pressure” at the top of the hour
‘Turn off CS100 after measurement
If (IfTime (0,60,min)) Then
pressure = CS100_temp
WriteIO (&b1000,&b0)
EndIf
CallTable met_data
NextScan
EndProg
7
CS100 Barometric Pressure Sensor
Example 2. Sample Program for CR10X (Edlog) Datalogger
;{CR10X}
;
*Table 1 Program
01: 1 Execution Interval (seconds)
;Turn on CS100 one minute before the hour
;
1: If time is (P92)
1: 59 Minutes (Seconds --) into a
2: 60 Interval (same units as above)
3: 48* Set Port 8* High
;Measure CS100 at the top of the hour
;
2: If time is (P92)
1: 0 Minutes (Seconds --) into a
2: 60 Interval (same units as above)
3: 30 Then Do
3: Volt (SE) (P1)
1: 1 Reps
2: 15 2500 mV Fast Range
3: 6 SE Channel
4: 1 Loc [ P_mb ]
5: 0.2 Multiplier
6: 600 Offset
;Turn off CS100
;
4: Do (P86)
1: 58* Set Port 8* Low
5: End (P95)
6: If time is (P92)
1: 0 Minutes (Seconds --) into a
2: 60 Interval (same units as above)
3: 10 Set Output Flag High (Flag 0)
7: Real Time (P77)
1: 0110 Day,Hour/Minute (midnight = 0000)
;Store in high resolution mode to retain 0.01mb resolution
;
8: Resolution (P78)
1: 1 High Resolution
9: Sample (P70)
1: 1 Reps
2: 1* Loc [ P_mb ]
*Table 2 Program
02: 0.0000 Execution Interval (seconds)
8
CS100 Barometric Pressure Sensor
⎧
*Table 3 Subroutines
End Program
-Input Locations1 P_mb
* Proper entries will vary with program and datalogger channel, and input location assignments.
5.4 Output Resolution
When storing the values from the CS100 to a data table or to a datalogger’s
final storage location, care must be taken to choose suitable scaling of the
reading, or to store the value with adequate resolution to avoid losing useful
resolution of the pressure measurement. The default resolution (low
resolution) for Campbell Scientific dataloggers is limited to a maximum of four
digits. Even then, the maximum digit value that can be displayed is 6999 for
Edlog dataloggers, and 7999 for the CRBasic d a taloggers. If you use this
option with barometric data scaled in millibars (hPa), a reading above
799.9 mb for CRBasic dataloggers or 699.9 mb for Edlog dataloggers will lose
one digit of resolution, e.g. at 900 mb, the resolution is limited to 1 mb.
To retain 0.01 mb resolution, you either need to deduct a fixed offset from the
reading before it is stored to avoid exceeding the 799.9 for CRBasic
dataloggers or 699.9 for Edlog dat a l og ge rs threshold, or output the barom e t ri c
reading in high resolution format. This can be done by using the IEEE4 format
for the CR800, CR850, CR1000, CR3000, CR5000, and CR9000(X)
dataloggers or using the Resolution (P78) instruction for our Edlog
dataloggers. The default data output format for CR200(X) series datalogger is
IEEE4.
6. Correcting Pressure to Sea Level
The weather service, most airports, radio stations, and television stations
reduce the atmospheric pressure to a common reference (sea level). Equation 1
can be used to find the difference in pressure between the sea level and the site.
That value (dP) is then added to the offset (600 mb in our example programs)
in the measurement instruction. U. S. Standard Atmosphere and dry air were
assumed when Equation 1 was derived (Wallace, J. M. and P. V. Hobbes,
1977: Atmospheric Science: An Introductory Survey, Academic Press,
pp. 59-61).
⎪
⎛
1013 25 11
dP
=−−
The value dP is in millibars and the site elevation, E, is in meters. Add dP
value to the offset in the measurement instruction.
⎨
.
⎜
⎝
⎪
⎩
E
44307 69231
.
5.25328
⎞
⎟
⎠
⎫
⎪
⎬
(1)
⎪
⎭
Use Equation (2) to convert feet to meters.
9
CS100 Barometric Pressure Sensor
Eft
Em
()
The corrections involved can be significant: e.g. at 1000mb and 20°C,
barometric pressure will decrease by 1.1mb for every 10 meter increase in
altitude.
()
.=3281
(2)
ft m
7. Maintenance and Calibration
Since the sensor is semi-sealed, minimum maintenance is required:
1. Visually inspect the cable connection to ensure it is clean and dry.
2. Visually inspect the casing for damage.
3. Ensure that the pneumatic connection and pipe are secure and undamaged.
The external case can be cleaned with a damp, lint-free cloth and a mild
detergent solution.
Contact Campbell Scientific, Inc. (435-753-2342) for an RMA number before
returning the sensor for recalibration. You may also return the unit directly to
Setra for recalibration.
CAUTION
Should you lose the five terminal connector (p/n 16004), the replacement part
can be purchased from Campbell Scientific, Inc. Contact Campbell Scientific,
Inc. to purchase the part.
The CS100 is sensitive to static when the backplate is
removed. To avoid damage, take adequate anti-static
measures when handling.