14968 02 SATURO_Pages 14968_SATURO_Print SATURO Print

User Manual: 14968_SATURO_Print

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14968-02

12.29.2017

TABLE OF CONTENTS

1. Introduction ..............................................................................................1

2. Operation ................................................................................................... 2

2.1 Installation ................................................................................................2

2.2 Functionality .............................................................................................3

2.2.1 Setting up a Test ..............................................................................3

2.2.2 Starting a Test ..................................................................................6

2.2.3 Stopping a Test ................................................................................7

2.2.4 Downloading Data ............................................................................7

3. System .........................................................................................................9

3.1 Specifications ............................................................................................9

3.2 Components ............................................................................................ 10

3.2.1 Control Unit .................................................................................... 11

3.2.2 Insertion Ring ................................................................................ 17

3.2.3 Infiltrometer Head ......................................................................... 18

3.2.4 Water Supply Tank ......................................................................... 18

3.3 Theory ...................................................................................................... 19

4. Service ....................................................................................................... 23

4.1 Calibration ............................................................................................... 23

4.2 Maintenance ............................................................................................ 25

4.3 Troubleshooting ....................................................................................... 26

4.4 Customer Support.................................................................................... 29

4.5 Terms and Conditions .............................................................................. 29

References ....................................................................................................32

Index .................................................................................................................33

Enter

BACK

POWER / MENU

33

INDEX

C

calibration 23–25

components

charger 9, 11

control unit 11

depth sensor 18

infiltrometer head 18

insertion ring 17

USB port 11

water supply tank 18–19

connections 12

contents. Seecomponents

customer support 29–33

F

field saturated hydraulic conductivity 1,

19–23

I

infiltration rate 5

installation 2

K

Kfs 1, 9, 19–23

L

lateral flow 20

M

maintenance

battery 26

cleaning 25–26

infiltrometer head 25

insertion ring 25

water pump 25

P

ponding depths 21

Q

quasi-steady state 5, 22

R

references 32

running a test

downloading 7–8

starting 6

stopping 7

S

SATURO Downloader 7–8

screen

about 17

contrast 16

date 15

diagnostics 16

flux 13

pressure 13

results 14

status 13

time 15

units 15

water level 14–15

water pump calibration 14

service. Seemaintenance

settings

hold time 5

pressure 4

pressure cycles 5

soak time 5–6

setup. Seemaintenance

sorptivity 20

specifications 9

T

tab

Configuration 14–17

Data 17

Reading 13–14

terms and conditions 29–33

theory 19–22

troubleshooting 26–33

32

SERVICE

REFERENCES

Bouwer H. 1986. Intake rate: Cylinder infiltrometer. In Klute A., editor, Methods of soil

analysis: Part 1—Physical and Mineralogical Methods. 2nd ed. Madison (WI): ASA and

SSSA. 825−844.

Dane JH and Topp GC, editors. 2002. Methods of soil analysis: Part 4—Physical Methods.

Madison (WI): Soil Science Society of America Inc.

Daniel DE. 1989. In situ hydraulic conductivity tests for compacted clay. J. Geotech. Eng. 115(9).

Nimmo JR, Schmidt KM, Perkins KS, and Stock JD. 2009. Rapid measurement of field-

saturated hydraulic conductivity for areal characterization. Vadose Zone J. 8(1): 142−149.

Reynolds WD and Elrick DE. 1990. Ponded infiltration from a single ring: I. Analysis of steady

flow. Soil Sci. Soc. Am. J. 54(5): 1233−1241.

Swartzendruber D and Olson TC. 1961. Sand-model study of buffer effects in the double-ring

infiltrometer. Soil Sci. Soc. Am. Proc. 25(1): 5−8.

Swartzendruber D and Olson TC. 1961. Model study of the double ring infiltrometer as

affected by depth of wetting and particle size. Soil Sci. 92(4): 219−225.

1

SATURO

1. INTRODUCTION

Thank you for choosing the SATURO Infiltrometer from METER Group. This manual should

help you understand the functionality of SATURO, make high-quality Kfs measurements, and

get the most out of the instrument.

SATURO was designed to be an automated instrument for measuring permeability

and field saturated hydraulic conductivity (

Kf s ) in soil. It utilizes a multipressure head

analysis approach to simplify the corrections for three-dimensional flow from a single-

ring infiltrometer, allowing for quick measurements of hydraulic conductivity without

needing postprocessing. This automated approach reduces error in the hydraulic

conductivity assessment (Reynold and Elrick 1990).

Verify all instrument contents shipped and appear in good condition:

• Control unit

• Two insertion rings: 5-cm depth and 10-cm depth

• Driving plate

• Infiltrometer head

• Charging adapter

• Two collapsible water tanks

• 6.4-mm (1/4-in) diameter tube for air output

• 9.5-mm (3/8-in) diameter tube for water output

• 7.9-mm (5/16-in) diameter tube for water input

• Metal file

• Driving mallet

• Flathead screwdriver

2

OPERATION

2. OPERATION

Please read all instructions before operating the SATURO to ensure it performs to its

full potential.

2.1 INSTALLATION

Follow the steps listed in Table 1 to set up the instrument.

Table 1 Installation

Preparation

Verify Access to Water

Identify a source of water on site or bring water to the site.

Charge Battery

Charge the control unit battery.

Renew the charge after returning from the fi eld.

Download Software

Install the SATURO Downloader to view fi les in the fi eld (Section 2.2.4).

Installation

Install Insertion Ring

Remove rocks, sticks, and other large debris from the surface where the ring will

be installed at the desired test location.

Place the insertion ring on the soil and fi t the driving plate on top.

Hammer on the inner circle of the driving plate until the insertion ring is fl ush

with the top of the soil, ensuring there are no gaps between the soil and ring

sidewalls.

Remove the driving plate.

For hill installation, install the insertion ring so that the infi ltrometer head will

be perpendicular to the slope of the hill with interior sensor to the left or right.

Set Up Infi ltrometer Head

Clear all grass and debris from the lip of the insertion ring and clamp the

infi ltrometer head onto the insertion ring to form a seal.

A clean seal ensures accurate pressure readings. Do not clamp too tightly, as this

can lead to warping of the insertion ring. Clamps can be tightened and loosened

with a small fl at head screwdriver as needed.

31

SATURO

will not be affected. Each term not so declared invalid or unenforceable will be valid and

enforced to the fullest extent permitted by law and the rights and obligations of the parties

will be construed and enforced as though a valid commercially reasonable term consistent

with the undertaking of the parties under the order has been substituted in place of the

invalid provision.

SET-OFF. The Buyer may not set-off any amount owing from the Seller to the Buyer against

any amount payable by the Buyer to the Seller whether or not related to this contract.

30

SERVICE

delivery or, if transportation charges are prepaid by the Seller, the Buyer will reimburse the

Seller upon receipt of an invoice from the Seller. The Buyer is obligated to obtain insurance

against damage to the goods being shipped. Unless otherwise specified, the goods will be

shipped in the standard Seller commercial packaging. When special packing is required or, in

the opinion of the Seller, required under the circumstances, the cost of the special packaging

shall be the responsibility of the Buyer.

INSPECTION AND ACCEPTANCE. Goods will be conclusively deemed accepted by the Buyer

unless a written notice setting out the rejected goods and the reason for the rejection is

sent by the Buyer to the Seller within 10 days of delivery of the goods. The Buyer will place

rejected goods in safe storage at a reasonably accessible location for inspection by the

Seller.

CUSTOM GOODS. There is no refund or return for custom or nonstandard goods.

WARRANTIES. The Seller warrants all equipment manufactured by it to be free from defects

in parts and labor for a period of one year from the date of shipment from factory. The liability

of the Seller applies solely to repairing, replacing, or issuing credit (at the Seller’s sole

discretion) for any equipment manufactured by the seller and returned by the Buyer during

the warranty period. SELLER MAKES NO SEPARATE OR OTHER WARRANTY OF ANY NATURE

WHATSOEVER, EXPRESS OR IMPLIED, INCLUDING THE WARRANTY OF MERCHANTABILITY

OR FOR A PARTICULAR PURPOSE. There shall be no other obligations either expressed or

implied.

LIMITATION OF LIABILITY. Seller will not be liable to the Buyer or any other person or entity

for indirect special, incidental,consequential, punitive, or exemplary damages in connection

with this transaction or any acts or omissions associated therewith or relating to the sale

or use of any goods, whether such claim is based on breach of warranty, contract, tort, or

other legal theory and regardless of the causes of such loss or damages or whether any other

remedy provided herein fails. In no event will the Seller’s total liability under this contract

exceed an amount equal to the total amount paid for the goods purchased hereunder.

WAIVER. In the event of any default under or breach of the contract by the Buyer, the Seller

has the right to refuse to make further shipments. The Seller’s failure to enforce at any time

or for any period of time the provisions of this contract will not constitute a waiver of such

provisions or the right of the Seller to enforce each and every provision.

GOVERNING LAW. The validity, construction, and performance of the contract and the

transactions to which it relates will be governed by the laws of the United States of America.

All actions, claims, or legal proceedings in any way pertaining to this contract will be

commenced and maintained in the courts of Whitman County, State of Washington, and the

parties hereto each agree to submit themselves to the jurisdiction of such court.

SEVERABILITY. If any of the Terms and Conditions set out in this contact are declared

to be invalid by a court, agency, commission, or other entity having jurisdiction over the

interpretation and enforcement of this contract, the applications of such provisions to

parties or circumstances other than those as to which it is held invalid or unenforceable

3

SATURO

Table 1 Installation (continued)

Installation

(continued)

Connect the hoses and sensor cable to the designated fi ttings on the

infi ltrometer head. Each input and output line is purposefully a different size of

tubing to help prevent a mismatch. If a tube does not snugly fi t into a connection,

it is probably in the wrong one.

Set Up the Water Tank

Fill the water tank and connect it to the control unit.

Fully open the water valve.

The water tank may not hold enough water for tests in highly permeable soils. To

use a larger container, place the tube at the bottom of the container and ensure

the tube remains underwater throughout the test.

Set Up Control Unit

Place the control unit on a stable surface.

Connect the three hoses and sensor cable to the corresponding ports on the

control unit.

Power on the control unit.

2.2 FUNCTIONALITY

Follow the steps in the following sections to collect data.

2.2.1 SETTING UP A TEST

1. Press the POWER/MENU button on the control unit to power on the device.

The last test results will appear on the screen.

2. Press Enter to view the Test Setup screen

This screen is used to name the test and confi gure test settings (Figure1).

Figure1 Test Setup screen

3. Name the test.

a. Select Name to create a test name.

4

OPERATION

b. Highlight letters and press Enter after each one (Figure2).

A decimal point is not allowed as the first character of a test name.

Toggle between upper and lower case by selecting the boxed up arrow in the lower right

of the screen.

To add a space or delete a character, navigate to the test name and use the RIGHT or

LEFT buttons, respectively.

The test name can have up to 20 characters.

Figure2 Name screen

4. Select Done and press Enter to save the new test name.

Press BACK to cancel without saving changes.

NOTE: When downloading tests as a comma-separated value file format (*.csv), the degree symbol and ± symbol

are omitted from the test name in the test summary information.

5. Confi gure test settings by selecting Settings.

Different soil types may require different parameters for an optimum infi ltration test.

Adjust settings to change pressure heads, soak time, number of cycles, and hold time as

well as to inform the control unit of the insertion ring depth ( Figure3).

Figure3 Settings options

a. Set desired hydrostatic pressure.

Hydrostatic pressure for the low and high pressure heads must be between 0 and

40 cm. Generally, soils with high infiltration rates require lower pressure head settings

than soils with low infiltration rates. A pressure difference of at least 5 cm between

the low and high pressure heads is normally recommended, except in sites with high

infiltration rates. In such cases, a pressure difference of 2 cm is sufficient to help

29

SATURO

4.4 CUSTOMER SUPPORT

Customer service representatives are available for questions, problems, or feedback Monday

through Friday, 8 am–5 pm Pacific time.

Email: support.environment@metergroup.com

sales.environment@metergroup.com

Phone: +1.509.332.5600

Fax: +1.509.332.5158

Website: metergroup.com

If contacting METER by email or fax, please include the following information:

Name

Address

Phone

Email address

Instrument serial number

Description of the problem

NOTE: For SATURO Infiltrometers purchased through a distributor, please contact the distributor directly for assistance.

4.5 TERMS AND CONDITIONS

CONTRACT FORMATION. All requests for goods and/or services by METER Group, Inc. USA

(METER) are subject to the customer’s acceptance of these Terms and Conditions. The

Buyer will be deemed to have irrevocably accepted these Terms and Conditions of Sale

upon the first to occur of the Buyer’s issuance of a purchase order or request for goods or

services. Unless expressly assented to in writing by METER, terms and conditions different

are expressly rejected. No course of dealing between the parties hereto shall be deemed to

affect or to modify, amend or discharge any provisions of this agreement.

PRICES AND PAYMENT. Invoice prices will be based upon METER prices as quoted or at

METER list price in effect at the time an order is received by the Seller. Prices do not include

any state or federal taxes, duties, fees, or charges now or hereafter enacted applicable to the

goods or to this transaction, all of which are the responsibility of the Buyer. Unless otherwise

specified on the invoice, all accounts are due and payable 30 days from the date of invoice.

Unpaid accounts extending beyond 30 days will be subject to a service charge of 2% per

month (24% per annum). Should Seller initiate any legal action or proceeding to collect on

any unpaid invoice, Seller shall be entitled to recover from Buyer all costs and expenses

incurred in connection therewith, including court costs and reasonable attorney’s fees.

RISK OF LOSS AND DELIVERY TITLE. Liability for loss or damage passes to the Buyer when

the Seller delivers the goods on the Seller’s dock or to the transporting agent, whichever

occurs first. The Seller has the right to deliver the goods in installments. Shipping and

delivery dates communicated by the Seller to the Buyer are approximate only.

SHIPMENT. In the absence of specific shipping instructions, the Seller, if and as requested

by the Buyer, will ship the goods by the method the Seller deems most advantageous. Where

the Seller ships the goods, the Buyer will pay all transportation charges that are payable on

28

SERVICE

Table 3 Troubleshooting SATURO (continued)

Problem Possible Solutions

“No depth sensor!”

Check sensor connection to the control unit.

Verify it is measuring correctly by checking the Water Level value

on the Diagnostics screen.

If these actions do not fi x the issue, contact Customer Support.

“Pressure limit exceeded!”

Check tubing for possible kinks or blockages.

NOTE: This error occurs when the air pressure in the chamber is over

60.0cm or below −50.0 cm and stops the test.

“Temperature too high!”

Move the system into a cooler environment. Make sure it is out of

direct sunlight. After the system has cooled, turn the power off

and on again to clear the temperature too high message.

NOTE: This error occurs when the air temperature is above the minimum

operating temperature (50 °C) while a test is running and stops the test

when this occurs.

“Temperature too low!”

Move the system into a warmer environment. After the system has

warmed, turn the power off and on again to clear the temperature

too low message.

NOTE: This error occurs when the air temperature is below the minimum

operating temperature (0 °C) while a test is running. Water frozen in the

system could cause damage. The error will stop the test.

Control unit becomes

unresponsive

Charge the battery.

Press and hold the BACK button for more than 7 s to restart.

If these actions do not fi x the issue, contact Customer Support.

“Date and time were reset!”

Ensure the battery is fully charged and update the date and time

in the Settings menu.

If this action does not fi x the issue, contact Customer Support.

“Missing bootstrap loader!

See Manual.”

This error means fi rmware updates will not be possible on this

instrument unless the instrument is serviced by Customer

Support.

The instrument may be used without consequences, but contact

Customer Support for servicing so the instrument fi rmware can

stay up to date with the latest features and bug fi xes.

5

SATURO

reduce water usage. Table 2 provides rough guidelines to determine initial pressure

head settings. These values are starting points only and should be adjusted for the

particular soil based on experience.

b. Set soak time.

During soak time, the infiltrometer applies water to achieve saturation of the soil

before beginning the pressure cycles. A good introductory soak time is approximately

20 min, though the exact length depends largely on soil type and antecedent soil

moisture (Table 2). During soak time, pressure is maintained at the low pressure head.

Table 2 Soak time and pressure head confi gurations

Soil Type

Soak

Time

(min)

Low

Pressure

Head (cm)

High

Pressure

Head (cm)

Hold Time

at Pressure

(min)

Pressure

Cycles

(count)

Total

Run Time

(min)

Dry loamy sand 25 5 10 15 3 115

Wet loamy sand 15 5 10 15 2 75

Dry silt loam 30 5 15 20 3 150

Wet silt loam 15 5 15 20 2 95

Dry clay (poor structure) 30 5 20 25 3 180

Wet clay (poor structure) 15 5 20 25 2 115

Dry clay (strong structure) 25 5 10 20 3 145

NOTE: These values are a rough starting point only. Soil conditions dictate the optimal settings for the test. Use

lower pressure head settings for soils dominated by macropore flow. If necessary, reduce the pressure head settings

to allow the instrument to keep up with the flow rates.

c. Set the number of pressure cycles.

One pressure cycle is equivalent to a full run at the two different pressure heads. The

control unit takes the average infiltration rates at the different pressure heads during

the last pressure cycle to calculate Kf s . Multiple pressure cycles ensure the steady

state infiltration rate was reached.

At first, the infiltration rate is large. Steady state or quasi-steady state may be

achieved when the infiltration rate charted over time levels into infinite time (Dane and

Topp 2002). Wait for the flux chart to stabilize to determine if quasi-steady state has

been reached. If there is a decrease in flux rate, redo the test or add another cycle.

d. Set the hold time (Figure4).

The hold time determines how long the pressure is held at each pressure head and

applies to both pressure cycles (i.e., if the hold time is 20, both the low and high

pressure holds for 20 min).

e. Select the correct insertion ring depth.

6

OPERATION

Run time

Soak Hold Hold Hold Hold

Low pressure

High pressure

Cycle 2Cycle 1

Figure4 Run time diagram

6. After the settings are confi gured, press BACK to go to the Test Setup screen.

2.2.2 STARTING A TEST

1. On the Test Setup screen, select Start.

The infi ltrometer displays a message to check tubing and connections.

2. Press Enter to begin the test.

The infi ltrometer will pump water from the water tank until the water level reaches 5 cm.

It then begins the soak time, while maintaining a level of 5 cm.

The graph feature displays incremental data during a test. The infi ltrometer records a data

point every minute throughout the duration of the test.

3. It is not necessary to supervise the system during a test, but check the water level

intermittently to ensure a constant supply.

Test results will display automatically at the end of the test (Figure5).

NOTE: See Section 3.2.1 for details on viewing graphs of flux, water level, and pressure.

Figure5 Test complete screen

Pressing BACK returns the display to the Reading screens. Pressing Enter on any of the

Reading screens returns the display to the Name screen to review test settings.

27

SATURO

Table 3 Troubleshooting SATURO (continued)

Problem Possible Solutions

Control unit shows low battery

Charge the battery to ensure it is fully charged.

NOTE: This error occurs when the battery voltage drops below the

minimum voltage at which the water pump can operate (11.1 V) during a

test and stops the test.

“Data memory is full.” Download the data from the infi ltrometer and erase the stored

data on the infi ltrometer before performing a new test.

Test failed to reach the

target water level

NOTE: The control unit will initially display “Water level warning!” If the

water level remains below the water level sensor (4.3 cm) for more than

10min, SATURO will stop the test and the control unit will display “Water

level error!”

Check that the water supply is connected and water is able to

easily fl ow from the water supply through the control unit into the

infi ltrometer head.

Check for leaks around the seal of the infi ltrometer head.

If SATURO is on a slope, the slope may be too great, and the water

level will not reach the sensor.

If there are no apparent leaks, the location may have an

infi ltration rate that exceeds the capacity of SATURO. Try

sampling a new location or adding a second water supply to

proceed with themeasurements.

NOTE: Soils with extremely high infiltration rates could cause the water

inside the chamber to remain below 4.3 cm, if the water pump cannot fill

the chamber at a rate greater than the soil’s infiltration rate.

Water is leaking between

seal of infiltrometer head

and insertion ring

Remove the infi ltrometer head and check for debris (grass, leaves,

loose soil, etc.) where the gasket seals with the insertion ring.

Remove any debris and reconnect the infi ltrometer head.

Check the tightness of the clamps. The clamps should only apply

enough pressure to slightly compress the gasket. If the clamps

are too tight, they can deform the insertion ring, causing a poor

seal. Adjust the clamp pressure with the screw on top of the

clamps asnecessary.

Selected pressure heads are

not being reached

Check tubing connections to ensure tubes are pressed all the way

into the push-to-connect fi ttings. The tubes should hit the back of

the fi ttings.

Infiltrometer does not

maintain pressure

Check tubing connections to ensure tubes are pressed all the way

into the push-to-connect fi ttings.

Check the infi ltrometer head seals for grass or debris. Verify the

clamps are not bent or deformed. Adjust the clamp screw to the

appropriate tightness to seal the ring as necessary.

NOTE: Tightening the clamp adjustment too tight will deform the metal.

26

SERVICE

If there is a significant change in pump calibration or the pump begins to become

inconsistent, it may need to be replaced. Contact Customer Support to request instrument

servicing.

SATURO is powered by 12-V, 7-A sealed lead acid battery. Over time, there will be a decrease

in the maximum charge value of the battery. If the battery does not come up to full capacity

after a full charge (typically 4–6 h), it will need to be replaced. Contact Customer Support for

information for a new battery and servicing.

The guidelines in Table 3 may also help identify any potential maintenance problems.

Table 3 Diagnostics screen metrics

Metric Acceptable Ranges/Required Servicing

Water Level Should range from −3.9 to 6.2 cm

Air Pressure Variable; should remain <40 cm

Battery ~11.1 to 13.7 V

Charging Status Variable; recommend beginning test with 100%

Temperature Do not exceed operating temperature; 0–50 °C

Cap Sensor NA

Water Pump Service at 500 h

Cartridge Service at 500 h

Air Pump Service at 500 h

4.3 TROUBLESHOOTING

Table 4 lists common problems and their solutions. If these solutions do not solve the issue,

contact Customer Support.

Table 4 Troubleshooting SATURO

Problem Possible Solutions

SATURO does not turn on Fully charge the battery.

If this does not fi x the issue, contact Customer Support.

“Firmware is corrupted!

See Manual.”

Check for fi rmware updates within the SATURO Downloader by

clicking Help > Check for Firmware Updates. Connect SATURO to

the computer and follow the instructions in the updater.

WARNING: Taking this action deletes all data from the unit.

NOTE: METER can extract data from units.

Test name already exists

If a new test has the same name as a completed test that is

already stored in memory, then this message will appear.

Rename the test.

7

SATURO

2.2.3 STOPPING A TEST

To stop a test, press BACK on any of the Reading screens and select Stop to cancel the

test(Figure6).

Figure6 Stop test warning

2.2.4 DOWNLOADING DATA

The SATURO Downloader application is used to download the data from SATURO, erase

stored data, set the date and time, and check for firmware updates for SATURO. Download

the application from metergroup.com/saturo-support before beginning the following steps.

1. Connect the USB cable to USB ports on a computer and on SATURO.

2. Open the SATURO Downloader application on the computer.

3. Select the fi le type by selecting Edit > Preferences > Data File and choosing the appropriate

fi le type (Figure7).

Data can be downloaded as .xlsx or .csv fi le.

Figure7 Change fi le type

8

OPERATION

4. Select the proper COM port and click Download (Figure8).

Figure8 SATURO Downloader dialog

5. After the download is complete, a prompt will ask if the data stored on the device should

be erased (Figure9).

Select Yes or No.

Figure9 Confi rm Erase prompt

25

SATURO

Figure36 Calibration Complete screen

To remove the updated calibration values, highlight Restore Defaults on the Water Pump

Calibration screen and press Enter.

Operators may run the calibration sequence as frequently as necessary to verify accurate

readings. Once the calibration is complete, the new value stores in SATURO firmware until

the next new calibration setting.

4.2 MAINTENANCE

Replacement parts can be ordered from METER. Contact Customer Support for more

information. The instrument can be sent in to update tubing, replace battery, inspect system,

and clean instrument. SATURO may also be returned to METER for maintenance and any old or

damaged parts will be replaced as a part of the maintenance program.

NOTE: Complimentary maintenance lasts for 1 year; Customer Support can provide parts and labor cost estimates

after this timeframe. See METER Terms and Conditions (Section 4.5) for more information.

Properly clean the equipment after each use to ensure the longevity of SATURO.

• Remove any soil on the insertion ring to reduce the amount of resistance when installing

the insertion ring.

• Remove soil particles and other materials on the infiltrometer head.

• Wipe down the three tubes with a wet rag.

• Inspect the insertion ring after each use for dents and dings incidental to normal use from

hitting rocks and hard roots. It is important to file away any dents or dings to the bottom

edge of the ring so the inner part of the ring is smooth. Dings and dents protruding towards

the inner portion of the ring can create channels and will allow for preferential flow.

• Purge water from water pump or run dry air through the tubing to dry out the control unit.

• Charge the control unit after each use.

The water pump on the SATURO is a peristaltic pump with a replaceable cartridge that

houses the tube and rollers. The tubing and rollers can wear out over time, typically around

5,000 hours of run time. The pump run time is tracked in the diagnostics screen of SATURO.

24

SERVICE

Figure33 Confi rmation screen

If using the mass method, tare the scale with the water tank. If using the volume method,

ensure the graduated cylinder is empty. Select Confirm (Figure34).

Figure34 Prepare Volume Measurement screen

Run the calibration water flow. Compare the reading on the scale or the measurement on the

cylinder to the infiltrometer default value on the Adjust Measured Value screen (Figure35).

Enter the new value from the scale or cylinder reading, and select Done. This value becomes

the new default water flow value (Figure36). SATURO uses this flow value to measure the

flow of water into the infiltrometer head.

Figure35 Adjust Measured Value screen

9

SATURO

3. SYSTEM

This section describes the specifications, components, and theory of the SATURO system.

3.1 SPECIFICATIONS

MEASUREMENT SPECIFICATIONS

Infi ltration Rate

Range 0.0038–115.0000 cm/h

Resolution 0.0038 cm/h

Accuracy ±5% of reading

Kfs

The Kfs values that can be effectively measured by SATURO are limited by the

listed minimum and maximum infi ltration rates. These depend on the pressure

heads applied to the water during infi ltration and to the three-dimensional fl ow

characteristics of the soil, so the measurement range of Kfs cannot be specifi ed

explicitly. SATURO will generally be able to make measurements on poorly to

moderately structured soils as coarse as medium sand, but the maximum infi ltration

rate can be exceeded by soils with excessive structure and especially by soils with

Water Level

Maintained at 5 cm

Pressure Head Ranges

0–40 cm (vacuum is applied for <5 cm settings)

Operating Temperature

0–50 °C

PHYSICAL SPECIFICATIONS

Charging Adapter

Power supply 18 V; 2.2 A

Range 18–24 VDC

Output

USB

Control Unit

31.8 cm (12.5 in) x 25.7 cm (10.1 in) x 15.3 cm (6.0 in)

Infi ltrometer Head

Total height 18.3 cm (7.2 in)

Inner diameter 17.2 cm (6.75 in)

Insertion ring

Inner diameter 14.4 cm (5.68 in)

Insertion depth 5 cm (1.97 in)

10 cm (3.94 in)

COMPLIANCE

Manufactured under ISO 9001:2015

2004/108/EC and 2011/65/EU

3.2 COMPONENTS

SATURO consists of four main components: the control unit, insertion ring, infiltrometer

head, and water supply tank (Figure10).

Enter

BACK

POWER / MENU

Figure10 SATURO components

23

SATURO

4. SERVICE

This section describes the calibration and maintenance of the SATURO infiltrometer.

Troubleshooting solutions and customer service information are also provided.

4.1 CALIBRATION

The water pump comes factory calibrated and is accurate to within ±5% of the reading at

the time of shipment. However, the water pump and tubing can wear, causing a change in the

volume of water flowing through the pump. Calibrate the pump every 6–12 months to ensure

accurate measurements.

Operators can use two methods, based on either mass or volume, to calibrate the pump.

The mass method is the most accurate, and the volume method is more convenient. Either

method is acceptable for calibration.

Prior to calibration, obtain either a scale accurate to 0.01 g or a 25-mL graduated cylinder, for

the mass or volume method respectively.

Press POWER/MENU, select Configuration, and select Water Pump Calibration (Figure31).

Press Enter on Type to toggle between Mass or Volume, and select Start.

Figure31 Water Pump Calibration screen

A message will prompt to connect to a water source and to attach the outgoing water tube

(Figure32). Connect a source of water to the water input port and press Enter.

Figure32 Setup Calibration screen

Both methods require that the water line is purged of air before running the calibration.

Select Purge. Repeat the process to run water through the tube until water runs clear with no

bubbles (Figure33).

22

SYSTEM

The hydraulic conductivity is then multiplied by the difference in quasi-steady state

infiltration rate for the last pressure cycle and divided by the difference in the measured

pressure head from the last pressure cycle.

Equation 4 is equivalent to Equation 41 from Reynolds and Elrick (1990) and removes the

dependence on soil characteristics and initial water content described by λ.

11

3.2.1 CONTROL UNIT

The SATURO control unit has seven buttons to navigate through screens and configure

settings (Figure11):

• When the device is off, press the POWER/MENU button to turn on the device.

Hold the POWER/MENU button down for more than 4 s to power off the device. This button

also navigates between different screen tabs.

• Pressing the BACK button returns the device to the parent screen. Pressing BACK on a

selection screen cancels any changes that have been made on that screen.

Holding BACK down for more than 7 s resets the device (hard reset).

• The UP, DOWN, LEFT, and RIGHT buttons on the directional pad allow navigation through

lists and scroll wheels. Pressing LEFT or RIGHT will highlight successive items in a list and

holding down the button will speed up scrolling.

• The Enter button selects the highlighted item to go to a submenu or save the highlighted

setting to memory.

Figure11 Control unit faceplate

The control unit is charged through a 18-V, 2.22-A, 40-W AC/DC charger. The unit takes

approximately 6 h to fully charge.

The control unit’s USB port takes a Type B to Type A USB to download data and to perform

firmware updates.

12

SYSTEM

There are four connections on the control unit (Figure12):

• Top left connection is for the 7.9-mm (5/16-in) water input (water tank to control unit).

• Bottom left connection is for the 9.5-mm (3/8-in) water output (control unit to

infiltrometerhead).

• Bottom right connection is for the sensor connection to the infiltrometer head.

• Top right connection is a 6.4-mm (1/4-in) air output (control unit to infiltrometer head).

Water input

Water output

Air input

Sensor

connection

Figure12 Control unit connections

The SATURO display (Figure13) features three main tabs designed for ease of use: Reading,

Configuration, and Data.

Time remaining Test status

Active tab

Configuration tab Battery level

Live updating

Data tab

Figure13 SATURO display elements

21

SATURO

Nimmo et al. (2009) gives F as shown in Equation 2

FCd Cb

DD

11

12

mm

D

=+ +

+=+ +

Equation 2

where

Dis the ponding depth (cm)

dis the insertion depth of the infiltrometer (cm)

bis the radius of the infiltrometer (cm)

∆is the constant for a given infiltrometer geometry; C1d + C2b (cm)

C1is 0.993

C2is 0.578

λis the reciprocal of the Gardner , which is a characteristic of the soil and its initial

water content (cm)

In Equation 2, ∆ is simply Equation 36 of Reynolds and Elrick (1990) multiplied by bπ, which

allows Figure2 and Equation 2 to be reconciled with Equation 37 of Reynolds and

Elrick(1990).

For two ponding depths, use Equation 3:

KD

i

D

i

fs

1

1

2

2

mmD

D

D

D

=++ =++

Equation 3

Rearranging one of the right terms to solve for λ in terms of Kfs, substituting this for λ in the

other right term, and simplifying yields

()

KDD

ii

fs 12

12

D

=-

-

Equation 4

where

D1is the actual high pressure head

D2is the actual low pressure head

∆is 0.993d + 0.578b (cm)

i1is infiltration rate at the high pressure head

i2is infiltration rate at the low pressure head

For ∆, d is the infiltrometer insertion depth and b is the infiltrometer radius. For the SATURO

5-cm insertion ring, d = 5 cm and b = 7.5 cm, so ∆ = 9.3 cm. For the 10-cm insertion ring,

d=10 cm and b = 7.5 cm, so ∆ = 14.3 cm.

20

SYSTEM

This approach overestimated Kfs due to lateral divergence of flow resulting from the

capillarity of the unsaturated soil and from the ponding in the ring (Bouwer 1986). Attempts

to eliminate flow divergence involved the addition of an outer ring to buffer the flow in the

inner ring (Figure30). However, the double-ring infiltrometer technique was ineffective at

preventing lateral flow from the inner ring (Swartzendruber and Olson 1961a, 1961b).

Measuring

cylinder

Mariotte

cylinder

Wetting

front

Buffer

cylinder

D

Water

b

d

Figure30 Cross section of a double-ring infi ltrometer

More recent research provides new methods for correcting for lateral flow. Reynolds

and Elrick (1990) presented a new analysis method of steady ponded infiltration into

a single ring, which accounts for soil capillarity, depth of ponding, ring radius (b), and

depth of ring insertion (d) and provides a means for calculating Kfs, matric flux (φm), and

macroscopic capillary length (). This analysis is known as the two-ponding head approach

(Reynolds and Elrick 1990).

The two -ponding head approach is the technique used by SATURO, though with some

modifications and simplifications. The easiest equation for this calculation is from

Nimmo et al. (2009). They compute Kfs as shown in Equation 1

KF

i

fs =

Equation 1

where i (cm/s) is the steady (final) infiltration rate (volume divided by area) and F is a

function that corrects for sorptivity and geometrical effects.

13

SATURO

READING TAB

The Reading tab is used to view screens related to the current tests, including charts from

the most recent flux, pressure, and water level readings. Use UP and DOWN to scroll through

the available reading screens.

• Status Screen. The Status screen shows the test status as Soaking (Figure14). When the

test is completed, it changes to the Results screen.

Figure14 Status screen during test

• Flux Screen. The Flux screen displays the flow rate of water flow through the infiltrometer

on a graph updated every minute (Figure15). The current measurement is indicated by a

flashing dot.

Figure15 Flux screen

• Pressure Screen. The Pressure screen displays the hydrostatic pressure (combined air and

water pressure) on a graph updated every minute (Figure16). The current measurement is

indicated by a flashing dot.

Figure16 Pressure screen

14

SYSTEM

• Water Level Screen. After a test is started, the water level above the soil ramps up to 5 cm.

The Water Level screen displays the current water level on a graph that is updated every

minute (Figure17). The current point is indicated by a flashing dot.

Figure17 Water Level screen

• Results Screen. After a test is complete, the Results screen replaces the Status screen.

It shows the resulting Kfs of the test (Figure18). The error (err) value also appears on the

Results screen. The err is the standard error of the Kfs reading and represents the amount

of noise in the measurement. Press UP and DOWN to change Reading screens or press the

POWER/MENU button to navigate to the Configuration tab.

SATURO will display the results from the last test if no test is running.

Figure18 Results screen

CONFIGURATION TAB

The Configuration tab is used to view and set global preferences (Figure19). Press the

POWER/MENU button to navigate to the Configurationtab. Use the UP and DOWN buttons to

scroll through options.

Figure19 Confi guration tab

• Water Pump Calibration. Water pump calibration is addressed in Section 4.1.

19

SATURO

Figure28 Water tank

3.3 THEORY

Field saturated hydraulic conductivity, Kfs (cm/s) is a fundamental soil hydraulic property

that describes the ease with which a fluid (usually water) can move through pore spaces or

fractures under field saturated conditions. One of the oldest and simplest methods for in situ

determination of Kfs has involved the measurement of ponded infiltration (D) from within a

single ring (with a radius b) pushed a small distance into the soil (d) (Figure29). The original

analysis used the measured steady flow rate, Qs(cm3/s), and assumed one-dimensional,

vertical flow to obtain Kfs from Bouwer (1986) and Daniel (1989).

Mariotte

cylinder

Wetting

front

Measuring

cylinder

D

d

b

Water

Figure29 Cross section of a single-ring infi ltrometer

18

SYSTEM

14.4 cm

6 cm

5 cm

Figure26 5-cm insertion ring

3.2.3 INFILTROMETER HEAD

The infiltrometer head houses the water level (depth) sensor (to control the water level),

water connection, and air connection with push-to-connect fittings (Figure27).

Ring clamps

Insertion ring

Infiltrometer head

Connectors

17.2 cm

18.3 cm

Figure27 Infi ltrometer head

3.2.4 WATER SUPPLY TANK

The water supply tank holds up to 5 gal and is sufficient for lower permeability sites

(Figure28). Some sites with higher infiltration rates will use more than 5 gal of water in the

time necessary to complete a measurement. The Y-connector may be used to connect two

water tanks to SATURO, doubling the water supply available for a measurement.

15

SATURO

• Date. Edit this screen to change the date saved in the control unit (Figure20).

Select the Date option in the Configuration tab. Use UP and DOWN to change the current

value and hold the buttons down to scroll quickly. Press RIGHT to move to the next value or

press LEFT to return to the previous value. Select Done to save changes or press BACK to

cancel without saving changes.

Figure20 Editing Date option

• Time. Edit this screen to change the time saved in the control unit (Figure21).

Select the Time option in the Configuration tab. Use UP and DOWN to change the current

value and hold the buttons down to scroll quickly. Press RIGHT to move to the next value or

press LEFT to return to the previous value. Select Done to save changes or press BACK to

cancel without saving changes.

Figure21 Editing Time option

• Units. Edit the preferred units on all device screens and the units that appear in

downloaded data (Figure22).

Select the Units option in the Configuration tab. Press Enter to cycle through the available

options on the highlighted measurement. Press BACK to return to the previous menu.

Figure22 Editing Units options

16

SYSTEM

• Contrast. Change the screen lighting contrast settings (Figure23).

Select the Contrast option on the Configuration tab. Use the directional buttons to change

the contrast to any value from 00–25. Use RIGHT and LEFT to highlight Done and press Enter

to save the new contrast setting. Press BACK to exit without savingchanges.

Figure23 Editing Contrast option

• Diagnostics. Shows all the current readings from the instrument: water level (the current

water level above the soil); air pressure (pressure in the head space of the infiltrometer

assembly); battery (current battery voltage); charging status (observed voltage from

charging power supply); temperature (internal temperature of the control unit); and cap

sensor (measured voltage of the cap sensor, which is proportional to the humidity within

the control unit) (Figure24).

The Diagnostics option also tracks the usage information for the water pump , cartridge,

and air pump to track when parts need to be replaced. This screen provides valuable

information for maintenance and troubleshooting ( Section 4.2). No changes can be made in

this screen.

Press BACK to return to the previous menu.

Figure24 Viewing the Diagnostics option

17

SATURO

• About. Displays the instrument’s serial number, firmware version, hardware version,

copyright date, and manufacturer’s name (Figure25).

Select the About option on the Configuration tab and press Enter. No changes can be made

in this screen. Press BACK to return to the previous menu

Figure25 Viewing the About option

DATA TAB

The Data tab provides access to past test data. Press the POWER/MENU button to

navigate to this tab.

• View. Lists prior tests stored on the device, most recent first.

To view a test, scroll to desired test and press Enter. The Results (including final Kfs value,

water level chart, pressure chart, and flux chart), Settings, and Raw Data screens from that

test can all be viewed. Scroll through the available information by using the UP and DOWN

buttons. Press BACK to return to the previous screen.

• Delete. Deletes all test data in device memory. There is no way to delete individual tests or

readings from the infiltrometer, it erases all test data.

WARNING: Deleting test data permanently removes it from the control unit, and it cannot be recovered. It is

recommended that you download any test data prior to deleting the test data from the instrument.

3.2.2 INSERTION RING

The insertion ring is available in two depths: 5 cm and 10 cm. The 5-cm insertion ring

(Figure26) is primarily designed for sites with good soil structure. It reduces the impact

from inserting the ring, so it is recommended for most sites. The 10-cm insertion ring was

designed for sites with a disturbed or loose soil surface as well as sites with high fluxes due

to macropores. The deeper insertion ring can also be helpful in forest or organic soils with a

deep duff or organic layer at the surface.