Campbell OXYGUARD TYPE III CS512 User manual

Campbell Scientific CS512
Oxyguard Type III
Dissolved Oxygen Probe
Revision: 12/06
Copyright © 2001-2006
Campbell Scientific, Inc.

Warranty and Assistance
The CS512 OXYGUARD TYPE III DISSOLVED OXYGEN 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
CAMPBELL SCIENTIFIC, INC. does not accept collect calls.

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CS512 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 Information.....................................................1
2. Specifications ..............................................................2
3. Optional Probe Accessories.......................................3
4. Optional Agitator .........................................................3
5. Application Information ..............................................4
6. Wiring............................................................................4
7. Programming ...............................................................5
8. Calibration....................................................................6
9. Maintenance.................................................................7
10. Agitator Control.........................................................7
Appendix
A. Dissolved Oxygen in Fresh Water Table...............A-1
Figures
1-1. CS512......................................................................................................1
4-1. Preventing Bio-fouling of the CS512......................................................3
4-2. CS512 with PT4 Agitator........................................................................4
10-1. Agitator Wiring.....................................................................................7
Table
6-1. Sensor Wiring..........................................................................................4

CS512 Table of Contents
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Examples
1. Sample Program using P1.......................................................................... 5
2. Sample Program using P2.......................................................................... 5
3. Sample Program using VoltSE .................................................................. 5
4. Sample Program using VoltDiff ................................................................ 5
5. Sample Program using VoltSE .................................................................. 5
6. Sample Program using P36........................................................................ 6
7. Sample Program using Expression ............................................................ 6
8. Sample Program using P86 and P22 Instructions ...................................... 8
9. Sample Program using Portset................................................................... 8
10. Sample Program using Portset................................................................. 8

1
Campbell Scientific CS512 Oxyguard
Type III Dissolved Oxygen Probe
An accurate and reliable sensor is a critical element in any measurement system. The
Oxyguard Stationary Probe meets these criteria for the measurement of dissolved oxygen.
1. General Information
The Oxyguard Stationary Probe is a galvanic probe which produces a millivolt
signal proportional to the amount of oxygen present in the measured medium.
Oxygen diffuses through the membrane onto the cathode, reacts chemically, and
combines with the anode. An electrical current is produced by this chemical
reaction which is converted from microamps to millivolts by an in-line resistor.
An in-line thermistor also conditions the signal providing automatic temperature
compensation. With these features, the probe produces a millivolt output
proportional to the oxygen present in the medium in which it is placed. The probe
consists of two parts, an upper part with cathode, anode and cable, and a lower part
comprising a screw on membrane cap with fitted membrane. The cap is filled with
electrolyte and simply screwed onto the top component.
The probe is self-polarizing and requires no external power source. There are two
wires to connect.
Because the probe's output is linear, it is possible to connect it directly to a data
acquisition system capable of handling the small millivolt signal.
The probe's robust construction and simple design make maintenance and
servicing it straightforward. There is no need to send the probe back to the factory
for servicing. It utilizes a strong, easy-to-clean and easy-to-change membrane in a
screw-on membrane cap. Regular servicing is not required. When necessary the
probe can be fully overhauled in five minutes.
FIGURE 1-1. CS512

Campbell Scientific CS512 Oxyguard Type III Dissolved Oxygen Probe
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2. Specifications
Principle of Measurement: Membrane covered galvanic oxygen probe
Output Signal: 2.5 to 5 mV per mg 1-1
Repeatability: Better than ±0.2 mg/l calibration temperature
equals measuring temperature ±5°C
Output Impedance: ∼1 kohm
Response Time: After equilibration, 1 minute for 95% of final
value
Materials of Construction:
Probe body:
O-rings:
Membrane:
Delrin
Membrane O-ring = Buna N
Body Seal O-ring = Viton
0.05 mm (2 mil) Teflon
Dimensions and Weight: 2.28” diameter x 2.3” height
15.9 oz.
Cable: standard length 7 m (23 ft); other lengths
available upon request
2-wire 22 awg shielded, PVC jacketed
Operating Conditions:
Temperature
Pressure:
Minimum Submersion Depth:
Minimum Water Flow:
0°to 40°C (32°to 122°F)
0 to 29 psig
60 mm (2 ½ in)
1 cm/s (.39 in/sec) across membrane
Calibration: In air or in air saturated water
Temperature Compensation: Automatic from 4°- 40°C (40°- 104°F)
Range of Dissolved Oxygen: 0-20 mg/l, 0-200% Sat
Ships with: 5 spare membranes with O-rings
50 ml electrolyte
cathode cleaning pad

Campbell Scientific CS512 Oxyguard Type III Dissolved Oxygen Probe
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3. Optional Probe Accessories
PT4-L — Agitator for stagnant conditions
18026 — DO electrolyte, 1 liter
18027 — Membrane kit, 10 membranes
4. Optional Agitator
The PT4 Agitator is a reliable and robust agitator for use in conjunction with
probes subjected to bio-fouling in ponds and stagnant water conditions.
O2probes require a minimum water velocity across their membranes to function
properly. Therefore, to measure DO in stagnant water conditions, it is necessary to
move the water past the membrane to get accurate and reliable DO measurements.
In many instances the water also has a high bio-loading and the probes become
fouled resulting in inaccurate DO measurements.
FIGURE 4-1. Preventing Bio-fouling of the CS512
The PT4 Agitator overcomes these problems. The device is designed so that a soft
bristle brush sweeps across the probe membrane or sensor tip. This sweeping
action of the brush provides the required water velocity as well as prevents the
membrane from becoming bio-fouled.
The optimum sweeping frequency depends upon the design of probe and type of
membrane used and water conditions. An ON-time of 0.25 seconds and OFF-time
of 5 seconds is suitable in most circumstances.
Agitator’s overall size: 7-1/8" x 3-1/4" diameter, 1-1/4 lb. (180mm x 83mm, 0.6 kg)
Supplied with 10 ft. (3 meters) cable.
Power required: 10.5 to 18 VDC at the agitator, 1.1 amps. Maximum ON-time is
3 seconds.

Campbell Scientific CS512 Oxyguard Type III Dissolved Oxygen Probe
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FIGURE 4-2. CS512 with PT4 Agitator
Optional Repeat Cycle Timer for Agitators: Reciprocating action may be
controlled by the optional solid state Repeat Cycle Timer. It sends 12 VDC pulses
to the agitator coil. The ON-time is 0.25 sec. The OFF-time is adjustable from 3
to 12 sec.; requires supply voltage 10 to 17 VDC; housed in watertight cylinder
6.6" x 2" diameter (170 mm X 50 mm).
5. Application Information
SCWin users: This manual was written primarily for those
whose needs are not met by SCWin. Your procedure is much
simpler: just add the CS512 probe (it’s in the water folder), save
your program, and follow the wiring shown in Step 2 of SCWIN.
6. Wiring
The CS512 probe can use one differential channel or one single-ended channel.
Differential wiring is better at rejecting electrical noise and ground loop error.
TABLE 6-1. Sensor Wiring
Colo
r
Functio
n
CR510, CR10X, CR800, CR850,
CR23X, CR1000, CR3000 CR200 Series
Whit
e Signal + Differential High, or Single-Ended Channel Single-Ended Channel
Blue Signal - Differential Low or AG Ground
NOTE

Campbell Scientific CS512 Oxyguard Type III Dissolved Oxygen Probe
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7. Programming
In the CR510, CR10X, and CR23X datalogger, Instruction P1 or P2 can be used.
Example 1 uses a single-ended measurement for the CS512 probe; example 2 uses
a differential measurement. The example measurement instructions that follow do
not store data to final storage. Additional instructions (typically P92, P77, and
output processing instructions such as P70) are required to store data permanently.
EXAMPLE 1. Sample Program using P1
1: Volt (SE) (P1)
1: 1 Reps
2: 24 250 mV 60 Hz Rejection Range ; code 23 used for CR23X
3: 1 SE Channel
4: 1 Loc [ DOmV ]
5: 1.0 Multiplier *See Calibration*
6: 0.0 Offset
EXAMPLE 2. Sample Program using P2
1: Volt (Diff) (P2)
1: 1 Reps
2: 24 250 mV 60 Hz Rejection Range ; code 23 used for CR23X
3: 1 DIFF Channel
4: 1 Loc [ DOmV ]
5: 1.0 Multiplier *See Calibration*
6: 0.0 Offset
In the CR1000, CR800, CR850, and CR3000 dataloggers, instruction VoltDiff
or VoltSE is used to measure the CS512 probe.
EXAMPLE 3. Sample Program using VoltSE
VoltSE (DOmV,1,mV250,1,1,0,_60Hz,1.0,0)
EXAMPLE 4. Sample Program using VoltDiff
VoltDiff (DOmV,1,mV250,1,True ,0,_60Hz,1.0,0)
In the CR200 series dataloggers, only the instruction VoltSE is used to
measure the CS512 probe.
EXAMPLE 5. Sample Program using VoltSE.
VoltSE (DOmV,1,1,1.0,0)

Campbell Scientific CS512 Oxyguard Type III Dissolved Oxygen Probe
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8. Calibration
The multiplier is used to calibrate the CS512 probe. To calculate the multiplier:
1) Program the datalogger using a multiplier of one.
2) Place the OxyGuard probe in the air, shaded from the sun. Wait for readings
to stabilize. This may take 15 minutes or more.
3) Determine the air temperature and barometric pressure.
4) Using a calibration chart such as that provided in the probe’s manual,
determine the oxygen concentration of the air.
5) Use the following equation to calculate the multiplier:
M = P/R
M = Multiplier
P = Concentration in PPM of the air (from the calibration chart in Appendix A)
R = The signal output of the OxyGuard probe when using a multiplier of one
6) Change the multiplier in the datalogger program from one to the calculated
number.
A more common way to enter the multiplier is to insert a separate instruction in
the program. This will allow a new multiplier to be added to the program
without rewriting, compiling, and downloading the program to the data logger.
In the CR510, CR10X, and CR23X, use Instruction P36. The multiplier is
entered into an input location called DOmult using the numeric display in
PC200W, PC208W, LoggerNet, PC400, PConnect, PConnectCE, or the
CR10KD.
EXAMPLE 6. Sample Program using P36
57: Z=X*Y (P36)
1: 1 X Loc [ DOmV ]
2: 2 Y Loc [ DOmult ]
3: 3 Z Loc [ DOppm ]
In all dataloggers that use CRBasic, an expression is written. The multiplier
value is entered into the expression through the Public Table using the numeric
display in PC200W, LoggerNet, PC400, PConnect, and PConnectCE.
EXAMPLE 7. Sample Program using Expression
DOppm = DOMult * DOmV