CPN 503 ELITE Hydroprobe Operating Manual

www.InstroTek.com

CPN 503 ELITE

™

Hydroprobe

OPERATING MANUAL

‘This page may be removed from the

manual to prevent the unauthorized

access to the restricted menu functions of

the InstroTek/CPN 503 Elite Hydroprobe.’

Restricted Menu Function

Access Code:

3548

Please note up to 2% of the mechanical components used in the gauge may be recycled material.

This page may be removed from the

manual to prevent the unauthorized

access to the restricted menu functions of

the InstroTek/CPN 503 Elite Hydroprobe.

503 Elite Hydroprobe ™

Operation Manual Version 12

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1. Table of Contents

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1. INTRODUCTION 2

2. GAUGE FUNCTIONS 9

3. OPERATION 13

4. CALIBRATION 15

5. LOGGING AND PROJECTS 25

6. MENU ITEMS 37

7. MAINTENANCE 41

8. OPERATION PRECAUTIONS 45

9. TROUBLESHOOTING 46

10. PRINT DATA/TRANSFERS 48

11. STANDARD COUNT INFORMATION 50

12. COUNTING STATISTICS 53

13. CONNECTOR PINOUTS 62

14. EXCEL SPREADSHEET 64

15. APPENDICES 65

16. INDEX 70

17. WARRANTY 74

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1. Introduction

Thank you for your purchase of the InstroTek/CPN Model 503 Elite Hydroprobe. The Model CPN 503 Elite HYDROPROBE, NEUTRON MOISTURE PROBE, measures the sub-surface moisture in soil and other materials by use of a probe containing a source of high-energy neutrons and a slow (thermal) neutron detector. The probe is lowered into a pre-drilled and cased hole that’s either 1.5 or 2 inches in diameter.

The source used in this gauge emits fast neutrons. Fast neutrons from the source interact with Hydrogen in water and thermalize (slow down) neutrons. The thermal or slow neutrons are then counted by the He3 tube. Increase in water content results in a proportional increase in thermal neutron counts detected by the tube. The moisture data is displayed directly in units of interest on the electronic assembly which is connected to the source shield assembly.

This state-of-the-art instrument offers a simple to operate but superior alternative to other methods of soil moisture monitoring. The operator needs minimal instructions. The probe is supplied with an 8 foot cable and ten adjustable cable stops. Additional stops and longer cable lengths are available upon request.

Upon retraction of the probe into the shield, the probe latches automatically in place and must be locked during transportation.

The complete assembly is supplied with a shipping and carrying container which contains accessory items, cable, operating manual, and other materials which the operator may wish to carry.

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CPN 503 Elite Features

The CPN 503 Elite Direct Readout Model Provides:

 Integral microprocessor for simple function selection.  Rapid, precise repeatable soil moisture measurements.  Light weight and portable.  Field service and component exchange with tools

provided.

 Storage and recall selection of linear calibrations for 32

soil or tubing types.

 Operator selected time of test, logging format and

units of measurements.

 Data transferred serially to a PC via a USB port using a

USB 2.0 A-male to B-male cable.

 Data downloaded to a USB mass storage device

(Thumb Drive).

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Functional Description

The CPN 503 Elite HYDROPROBE® operates by emitting radiation from an encapsulated radioactive source, Americium-241:Beryllium. To determine the moisture content in the soil, the Americium-241:Beryllium source emits neutron radiation into the soil under test. The high-energy neutrons are moderated by colliding with hydrogen in the moisture of the soil. Only low-energy, moderated neutrons are detected by the Helium-3 detector. A soil that is wet will give a high count per time of test. A soil that is dry will give a low count for the same period of time.

Fig 1.1 Operation of the 503 Elite HYDROPROBE®

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Model 503 Elite Hydroprobe and Standard

Accessories

Each 503 Elite is provided with a durable plastic shipping case and the items shown listed below. There are no special instructions for unpacking the 503 Elite Hydroprobe ®. It comes fully assembled.

1. 503 Elite Hydroprobe®

2. Padlock with Keys – 2 Locks

3. Shipping Case

4. 8 ft. (2.44 meter) Cable

5. 10 Cable Stops

6. Access Collar (1.5”)

7. Operating Manual

8. Spanner Wrench

9. AC Charger

10. Gauge Certificate

11. Leak Test Certificate

Fig 1.2 Standard Equipment

2 3 4 5 1

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Specifications

Dimensions/Shipping Weights:

Model

Weight

Length

Width

Height

Gauge

Only

15.7lbs

(7.12kg)

7.0”

(178mm)

6.8”

(173mm)

14”

(356mm)

Gauge &

Carry

Case

36.5lbs

(16.6kg)

13.0”

(330mm)

24.0”

(610mm)

10.0”

(254mm)

Probe

Weight

Length

Diameter

Model 1.5

1.7lbs

(0.77kg)

12.7”

(323mm)

1.50”

(38.1mm)

Performance:

Function - Sub-surface moisture measurements

Range - Linear calibration: 0 to 40% per volume, 0.40 g/cc, 25

pcf, 4.8 in/ft

Precision - 0.24% at 24% per volume at one minute

Count Time - User selectable from 1 to 960 seconds

Count Pre scale - 3.75 for 1 min, 15 for 4 min

Display - 4 lines x 20 character Liquid Crystal Display

Data

 Storage - 2 GB of storage  Format - Operator programmable  Notes - 0-99 notes of 19 characters each  Counts - 0-99 counts per record

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Data Output - USB A-B Male Cable download to personal

computer

Calibration - 32 user programmed (linear)

Units - in/ft, pcf, g/cc, %Moist, cm/30cm

Construction

 Body - Aluminum with epoxy paint & hard-anodize finish  Wear Parts - Stainless Steel

Electrical:

Power

 NiMH 7.5V 2500 mAh Battery Pack

Battery Life - 100 hours of operation

Environmental:

Operating Temperature

 Ambient - 32º to 150º F (0º to 66º C)  Storage - -4º to 140º F (-20º to 60º C)

Humidity (Non-Condensing) - 95%

Radiological:

Neutron Source - Maximum 1.85 GBq (50 mCi) Americium-

241:Beryllium

Encapsulation - Double-sealed capsule CPN-131

Shielding - Silicon-Based Paraffin

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Shipping Requirements:

RQ, UN 3332, RADIOACTIVE MATERIAL, TYPE A PACKAGE, SPECIAL FORM, 7

Special Form Approval - CZ/1009/S

An NRC or agreement state license is required for domestic use. Contact CPN - InstroTek for assistance in obtaining training for a license.

CPN - InstroTek reserves the right to change equipment specifications and/or design to meet industry requirements or improve product performance.

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CPN 503 Elite HYDROPROBE® Inspection

To familiarize yourself with the CPN 503 Elite HYDROPROBE®, perform the following review.

1. Remove the HYDROPROBE®

from the shipping case and place it on a solid flat surface, such as a concrete floor.

2. Examine the keyboard, the

display screen, the cable, probe, and shield box.

NOTE

The radioactive source is

located at the bottom part of

the probe.

Do not touch this part of the

probe or place yourself in front

of it.

3. Cable Stops

The gauge is supplied with ten each clamp-on cable stops. This will allow taking measurements at half foot increments in a root zone up to five feet deep. For a deeper root zone or for smaller increments, order more stops. Figure 1.4 shows a cross-section of the gauge. Use it to position the first stop so that the measurement point on the probe (as indicated by the band) is in the middle of the top foot of the root zone. Its actual location will depend upon how high the access tubes stick out of the soil. Install all tubes to the same height.

Fig 1.3 CPN 503 Elite

HYDROPROBE®

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For example, if the base of the gauge is 5.0 inches above the

soil, and you want to take the first measurement at 6 inches,

place the stop at 5.35 + 5.0 + 6.0 =16.35 inches above the stop reference line.

4. Tube Adapter Ring

The bottom of the gauge contains an oversize hole to allow inserting an adapter ring with a diameter to match the type of access tubing being used. The ring is secured by a screw through the front of the casting. Unless specified otherwise at the time of order, an adapter ring for aluminum tubing will be supplied. Adapter rings for other types (e.g. diameters) are available from CPN/InstroTek, Inc. or can be constructed locally.

Fig 1.4 503 Cross Section

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2. Gauge Functions

The CPN 503 Elite includes an updated keypad interface with menu related function keys.

Function Start/Enter: Take a reading and select from drop down

menu functions

On/Off: Power on/off function

No: Function key for software/menu requests

Yes: Function key for software/menu requests

Store: Store data and settings to an internal SD card

Time: Enter count time for the length of a reading

Esc: Escape key used to return to main menu or

previous screen

STD: Select Standard Count menu

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Menu: 14 Item gauge control functions (See Sect. 6 for

details)

Arrow Keys: Navigate through the menus

Numeric Expanded keypad aids in project and data Keys: entry

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Standard Count

Taking a Standard Count

Note: A new standard count should be taken at least once a day.

With the case on the ground, place the gauge on the CPN nameplate depression on the top of the case. No other radioactive sources should be within 30 feet of the gauge, and no source of hydrogen should be within 10 feet after starting the reading.

To initiate a new standard count, press STD. The display will show the last standard count and asks you “Would you like to take a new STD Count?” Select either (Yes/No).

The wax in the shield is not an infinite volume. Thus a standard count taken in this manner is subject to surrounding conditions. It is important that the standard count be taken in the same conditions as that used to establish the calibration, and that the conditions are the same each time.

See section 11 for further discussion on standard count.

Select TIME

The counting time is selected by pressing the TIME button on the keypad.

For a given counting rate, the counting time interval determines the precision of the measurement. The longer the time selected, the more precise the measurement. Correspondingly, the longer the counting times the fewer measurements that can be made in a day. Thus the time interval is normally selected as the minimum time that will meet your specific precision.

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For scheduling-type operation, a count time of 15 seconds will provide sufficient precision for irrigation scheduling.

See section 11 on Standard Count for a further discussion of precision.

Select UNITS

Gauge units are under menu item 8.

These are the different units the user can choose:

1. g/cc- grams of water/cubic cm of soil

2. lb/cf – pounds of water/cubic foot of soil

3. in/ft – inches of water/foot of soil

4. cm/30cm – centimeters of water/30 cm of soil

5. %moist – Water content (vol.%) = a* count ratio + b

6. Count – Raw gauge counts/unit time

The choice of display units will depend upon your use. Researchers will normally prefer grams per cubic centimeter (1) or percent volume (5), while irrigation schedulers use inches per foot (3) or centimeter per 30 centimeters (4).

Counts (6) are used for downloading to a software program and are helpful for troubleshooting. It is the same data, only differing by the conversion factor.

Once the units have been selected, then each time a Reading is taken, the display will be in the units selected.

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Fig 3.1 Operation of the 503 Elite HYDROPROBE®

3. Operation

Operating Procedures

Taking A Reading (Standard Count Required to Calculate Moisture)

Before taking a reading, you must select UNITS, TIME and CALIBRATION, or PROJECT. After this, lower the probe to the appropriate depth and press START.

Note: The gauge must have a valid standard count to function correctly.

After the count time, the gauge will display the results.

Project ORCHARD1

MC=1024 R=0.89

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Test Results

MC Moisture Count: Raw gauge counts/unit time

R Ratio: MC/Standard Count

M Moisture in selected units. (See page 12 for

changing units.)

The moisture is calculated with the following formula:

𝑀 = 𝑅 𝑥 𝐴 + 𝐵

A and B are from the selected calibration that is stored in the gauge.

32 different calibrations can be stored in the gauge. (See Section 4, Calibration)

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4. Calibration

The neutron probe is a source of fast or high energy neutrons and a detector of slow or thermal neutrons.

The fast neutrons are slowed down by collision with the nucleus of matter in the soil, and then absorbed by the soil matter. Since the mass of the nucleus of hydrogen is the same as that of a free neutron, the presence of hydrogen will result in a high field of thermal neutrons. Heavier elements will also slow down the neutrons, but not nearly so effectively. While it takes, on the average, only 18 collisions with hydrogen, it takes 200 with the next element normally found in agricultural soil.

The thermal neutrons are continually being absorbed by the matter in the soil. Boron, for example, has a high affinity for thermal neutrons. The resulting thermal neutron flux will depend upon a number of factors, both creating and absorbing thermal neutrons, but most importantly will be how much hydrogen is present. The neutron probe may thus be used as a measuring device for moisture in the soil, but it may require calibration for local soil conditions.

Field Calibration

A field calibration requires the probe, a volume sampler, a scale and a drying oven. Install the access tube in a representative point in the soil. Take probe readings in the tube and volume samples in pairs around the tube. Take them at the same depth and within a foot or two of the tube. Seal the volume samples in a sample can or plastic seal bag immediately after removing from the soil. Be careful not to

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compact the surrounding soil when taking the samples. Ideally (20) such measurement pairs should be taken over a range of moisture conditions.

An alternate method is to use a sampler of smaller diameter than the tube and take volume samples at each depth while making the hole to install the access tube. Then take probe readings at the same depths. This has the advantage that the calibration is performed on the tube to be used for scheduling.

Another alternate, popular with irrigation schedulers, is to only take two measurement pairs, one pair at field capacity and a second at a soil moisture condition near 50% depletion.

Weigh the soil samples wet and dry (24 hrs at 105º C in a vented oven). Calculate the moisture by weight and the dry soil density, and then combine to determine the soil moisture content in inches per foot as follows:

Ww – Wd (gm water) x Wd (gm soil) x 1 (cc water) x12

Inches per foot= Wd(gm soil) V(cc soil) (gm water)

Using linear graph paper, plot the probe readings in count ratio versus the volume samples in inches per foot.

Calibration

Fit the graph to a straight line. For a scatter diagram of 10 to 20 data pairs, do a linear regression on a hand calculator. For only two pairs, use the following equations to determine the slope and intercept.

MH - ML Slope: A = RH – RL Intercept: B = ML – A x RL Then: M = (A x r) + B

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Where: m = moisture in inches per foot

MH = high moisture value in inches per foot

Example: A field capacity of 3.8 in/ft gives a ratio of 1.500, while 50 percent depletion gives a ratio of 0.77.

3.8 - 1.90

A = 1.5 - 0.77 = 2.603 in / ft / count ratio

B = 1.9 - 2.603 x 0.77 = -0.1043 or M = 2.603 x r - 0.1043

The 503 Elite defines the slope and intercept with water on the vertical axis and ratio on the horizontal axis. If your data has been plotted with the axis reversed as shown in the following Figure, it will be necessary to transpose the slope and intercept terms before entering in the DR.

l A=A’

B’ B=A’

Laboratory Calibration

For a laboratory calibration, two known calibration points are needed. A high calibration standard can be a barrel of sand saturated with water (typically 0.32 gm/cc. i.e. 0.32 grams of

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water per cubic centimeter of soil, or 32% water by volume, or

3.84 inches of water per foot of soil). A low standard of dry sand would be 0.0 gm/cc. This is how the factory calibration is determined. It will be applicable for sandy soils with no significant organics.

Range

The linear calibration supplied with the 503 Elite is useful over the most commonly used moisture range, 0 to 40%. For use in moisture contents higher than this, it is necessary to have a special calibration that covers the intended range of use.

Entering Calibrations

Calibrations can be entered manually or by self-calibration.

Changing Existing Calibration:

 Press MENU – Use Arrow keys to select ’13. Calibration’  Press ENTER.  Use Arrow keys to select ‘2. Enter/Edit Cal’. Press Enter.

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 You will be prompted to enter the Password (3548). Enter it

and press STORE.

 Use the Arrow keys to select ‘1. Enter New Cal’. Press ENTER.

 Use the Arrow keys to select the calibration you wish to

change. You will be asked if you really wish to change the calibration.

 Press YES.

+ 57 hidden pages

CPN 503 ELITE Hydroprobe Operating Manual

Specifications and Main Features

Frequently Asked Questions

User Manual