Hach-Lange BODTRAK II User Manual

DOC022.53.90072

BODTrak™ II

USER MANUAL

02/2010,

Edition 2

Table of contents

Section 1 Specifications .................................................................................. 5

Section 2 General information ....................................................................... 7

2.1 Safety information .......................................................................................7

2.1.1 Use of hazard information ................................................................ 7

2.1.2 Precautionary labels ......................................................................... 7

2.2 Theory of operation ..................................................................................... 8

2.2.1 Oxygen transfer to sample ............................................................... 8

2.2.2 Pressure sensor function .................................................................. 9

2.2.3 Removing carbon dioxide ................................................................. 9

Section 3 Installation ...................................................................................... 11

3.1 Component list .......................................................................................... 11

3.2 Electrical installation ................................................................................. 12

Section 4 Operation ........................................................................................13

4.1 Operational controls .................................................................................. 13

4.1.1 Channel selection keys ................................................................... 14

4.1.2 The arrow keys ...............................................................................14

4.1.3 The ON key .................................................................................... 14

4.1.4 The OFF key ................................................................................... 14

4.2 Bottle connections .................................................................................... 14

4.3 Setting the clock ....................................................................................... 15

4.4 RS232 Interface ........................................................................................ 15

4.5 Downloading test results ........................................................................... 16

4.5.1 Import data ..................................................................................... 16

4.5.2 Data format ..................................................................................... 17

4.5.3 Printing test results ......................................................................... 18

Section 5 BODTrak™ II procedures .......................................................... 19

5.1 General Information .................................................................................. 19

5.2 Simplified procedure .................................................................................20

5.3 Hach GGA (glucose/glutamic acid) procedure ..........................................22

5.4 Hach Standard Method procedure ............................................................ 24

5.5 Completion steps for all procedures ......................................................... 27

5.5.1 Determination of results .................................................................. 30

5.6 Typical curves ........................................................................................... 32

5.7 Special considerations .............................................................................. 33

5.7.1 Sample dilution ...............................................................................33

5.7.2 Sample seeding .............................................................................. 33

5.7.3 Sample temperature ....................................................................... 33

5.7.4 Toxic materials ...............................................................................33

5.7.5 Chlorine .......................................................................................... 34

5.7.6 pH effect .........................................................................................34

5.7.7 Supersaturation .............................................................................. 34

Section 6 Maintenance .................................................................................. 35

6.1 Cleaning the instrument ............................................................................ 35

6.1.1 Sample bottles ................................................................................ 35

Table of contents

6.1.2 Stir bars and seal cups ....................................................................35

6.1.3 Bottle fences ...................................................................................35

Section 7 Troubleshooting ............................................................................37

7.1 High oxygen demand .................................................................................38

7.2 Nitrification .................................................................................................38

7.3 Excessive time lag .....................................................................................38

7.4 Sample temperature ..................................................................................38

7.5 Bottle leak ..................................................................................................39

Section 8 Replacement parts and accessories ......................................41

8.1 Replacement parts ....................................................................................41

8.2 Reagents ...................................................................................................41

8.3 Optional reagents ......................................................................................41

8.4 Accessories ...............................................................................................42

Section 9 Contact Information ......................................................................45

Section 1 Specifications

Specifications are subject to change without notice.

Table 1 Specifications

General

Range Selectable, 0 to 35, 0 to 70, 0 to 350, 0 to 700 mg/L

Dimensions 28.9 x 26 x 9.8 cm (11

External power supply

Capacity Six 492 mL bottles

Shipping weight 4 kg (8.8 lb)

Operating temperature 20 ºC (68 ºF)

Storage temperature 0 to 40 ºC (104 ºF)

Input: 110 to 240 V, 50/60 Hz, Output: 24 V, UL CSA, and TUV approved

Method performance specifications

On a standard containing 150 mg/L each of glucose and glutamic acid, a single analyst using 6 BODTrak™ II

Precision

Drift Less than 3 mg/L BOD in 5 days

Resolution 1 mg/L BOD

instruments and testing 44 samples obtained a mean of 235 mg/L BOD with a 95% confidence limit of distribution of 11 mg/L or a range of 224 to 246 mg/L BOD.

/8 x 10 ¼ x 3 7/8 inches)

Table 2 Certification

Certification

Hach Company certifies this instrument was tested thoroughly, inspected and found to meet its published specifications when it was shipped from the factory. The BODTrak II has been tested and is certified as indicated to the following instrumentation standards:

FCC Part 15, Sub-Part B, Class A Limits: Supporting test records by Intellistor, certified compliance by Hach Company Canadian Interference-Causing Equipment Regulation, ICES-003, Class A: Supporting test records by Intellistor, certified compliance by Hach Company EN 55011/CISPR 11(EMI) “B” Limits per 89/336/EEC EMC: Supporting test records by Intellistor, certified compliance by Hach Company EN 50082-1 (Immunity) per 89/336/EEC EMC: Supporting test records by Hach Company, certified compliance by Hach Company. Standards include:

• IEC 801-2 and EN 61000-4-2 (ESD)

• IEC 801-3 and EN V50140 (RF & EM Field)

• IEC 801-4 and EN 61000-4-4 (Fast Transient)

• EN 61000-4-5 (Surge)

Warranty: US 1 year; EU 2 year

Specifications

Table 2 Certification (continued)

Radio frequency interference

This Class A digital apparatus meets all requirements of the Canadian Interference-Causing Equipment Regulations. This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions:

(1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation.

Warning Changes or modifications to this unit not expressly approved by the party responsible for compliance could void the user’s authority to operate the equipment.

This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial environment. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instruction manual, may cause harmful interference to radio communications. Operation of this equipment in a residential area is likely to cause harmful interference, in which case the user will be required to correct the interference at their own expense. Shielded cables must be used with this unit to ensure compliance with the Class A FCC limits. Because this instrument operates on and generates radio frequency energy, interference to radio and television reception may occur. If such interference does occur, the operator should take the necessary steps to correct the interference. The following techniques of reducing the interference problems are easily applied:

• Disconnect power from the BODTrak II instrument to verify the instrument is the source of the interference.

• If the BODTrak II is plugged into the same outlet as the device with which it is interfering, try another outlet.

• Move the BODTrak II away from the device receiving the interference.

• Reposition the receiving antenna for the device receiving the interference.

• Try combinations of the above.

Section 2 General information

2.1 Safety information

Please read this entire manual before unpacking, setting up or operating this equipment. Pay attention to all danger and caution statements. Failure to do so could result in serious injury to the operator or damage to the equipment.

Make sure that the protection provided by this equipment is not impaired, do not use or install this equipment in any manner other than that specified in this manual.

2.1.1 Use of hazard information

DANGER Indicates a potentially or imminently hazardous situation which, if not avoided, will result in death or serious injury.

WARNING Indicates a potentially or imminently hazardous situation which, if not avoided, could result in death or serious injury.

CAUTION Indicates a potentially hazardous situation that may result in minor or moderate injury.

Important Note: Indicates a situation which, if not avoided, may cause damage to

the instrument. Information that requires special emphasis.

Note: Information that supplements points in the main text.

2.1.2 Precautionary labels

Read all labels and tags attached to the instrument. Personal injury or damage to the instrument could occur if not observed. A symbol, if noted on the instrument, will be included with a danger or caution statement in the manual.

This symbol, if noted on the instrument, references the instruction manual for operation and/or safety information.

Electrical equipment marked with this symbol may not be disposed of in European public disposal systems after 12 August of 2005. In conformity with European local and national regulations (EU Directive 2002/96/EC), European electrical equipment users must now return old or end-of life equipment to the Producer for disposal at no charge to the user.

Note: For return for recycling, please contact the equipment producer or supplier for instructions on how to return end-of-life equipment, producer-supplied electrical accessories, and all auxiliary items for proper disposal.

General information

2.2 Theory of operation

Respirometric Biochemical Oxygen Demand (BOD) is a test done at 20 °C (68 °F) in a controlled environment. The test period can be 5, 7 or 10 days, contingent on the analysis or protocol. The BOD test measures the quantity of oxygen consumed by bacteria that oxidize organic matter in a water sample. The test is used to measure waste loadings at wastewater treatment plants and to examine the efficiency of wastewater treatment.

BOD test results help find general oxygen uptake patterns. This lets operators estimate plant operating efficiency and find correct treatment procedures.

Advantages to the BODTrak™ II as an alternative to the dilution method are:

• Minimal time to prepare a sample.

• Decreased total test time.

• The BODTrak II method gives results comparable to the diluton method (BOD5)

in 2 to 3 days.

• Calibration and dissolved oxygen measurement are not necessary.

• The BODTrak II test is easy to monitor.

• The sample is stirred constantly and kept in natural conditions. This makes the

BODTrak II results similar to occurrences found in a natural environment. The dilution method supplies no additional oxygen to the sample. This causes a higher percentage of oxygen depletion and possible retardation of biochemical reactions.

• The BOD can be monitored at any time because the instrument continuously shows the BOD result. Pressure changes in the closed BODTrak II system are shown graphically in milligrams per liter (mg/L) on an LCD. The system supplies 360 uniform data points over the selected time period.

• The BODTrak II system continuously removes carbon dioxide from the system so that the pressure difference monitored is proportional to the quantity of oxygen used.

• Degassing can cause negative errors when heat is applied to a sample to achieve experimental temperature. The BODTrak II adjusts for this occurrence. The BODTrak II does not start the test until the temperature gets to equilibrium.

2.2.1 Oxygen transfer to sample

Bacteria in the sample use oxygen while consuming organic matter in the sample bottles. The air in the bottle above the sample contains 21% oxygen and replenishes the dissolved oxygen used by the bacteria. During the test period, stir bars continually mix the sample in each bottle. This moves oxygen from the air to the sample and helps simulate natural conditions.

General information

2.2.2 Pressure sensor function

The BODTrak II is sealed to prevent external atmospheric pressure changes in the test bottle. Pressure sensors monitor air pressure in the sample bottles. When oxygen is consumed, the pressure in the bottle head space drops. The pressure drop correlates directly to BOD.

2.2.3 Removing carbon dioxide

Carbon dioxide is made when microorganisms oxidize organic matter in the sample. The carbon dioxide must be removed from the system so it does not interfere with the measurement. Potassium hydroxide pellets put in the seal cup of each sample bottle before the test remove the carbon dioxide.

Section 3 Installation

3.1 Component list

Compare each item below to the items in the shipment. If an item is missing or damaged, refer to the manufacturer.

• BODTrak™ II instrument

• A UL/CSA approved 115 VAC power cord with a NEMA 5-15P style plug

• A 230 VAC harmonized power cord with a continental European plug

• Power supply, auto–switching between 115 V and 230 V

• 6 seal cups

• 6 BODTrak II amber sample bottles

• 6 BODTrak II magnetic stir bars

• Spatula scoop

• One package nutrient buffer solution pillows

• One container potassium hydroxide pellets

Installation

3.2 Electrical installation

The power adaptor supplies AC power to the IEC universal connector (Figure 1). The power switch powers the instrument on and off.

Figure 1 External connections

1 Power switch 3 RS232 connector 2 IEC universal connector

Section 4 Operation

4.1 Operational controls

The BODTrak™ II operator controls are shown in Figure 2.

Figure 2 Operational controls

1 Display 4 ON/OFF keys 2 Channel selection keys 5 Power indicator 3 Arrow keys

The ON/OFF keys start and stop a test. They do not power the instrument on and off.

Operation

4.1.1 Channel selection keys

Push the related channel selection key to show data for one of the 6 bottles.

The channel selection keys are also used in the instrument setup menu to choose a parameter to be edited (Table 3).

Table 3 Channel key setup parameters

Channel Parameter

1 Year (0-99) 2 Month (1-12) 3 Day (1-31) 4 Hour (0-24) 5 Minute (0-59) 6 Test Length (5, 7, or 10 days)

4.1.2 The arrow keys

The display shows a graph of BOD values on the vertical axis and time in days on the horizontal axis. Push the left and right arrow keys to move the cursor along the BOD curve to show the approximate coordinates (time, BOD) of the selected data point.

The time interval and BOD value of the data point are shown in the lower right of the display. The cursor is automatically placed at the most recently collected data point in a channel display.

Push and hold the two arrow keys at the same time to go into the instrument setup menu. The arrow keys are also used to change the time, date, test length and range.

4.1.3 The ON key

To access the range selection menu, push the ON key from a channel display screen. Then push and hold the ON key to start the test for the selected channel.

4.1.4 The OFF key

When a test is in DELAY or RUN modes, pushing and holding the OFF key manually ends the test. The instrument will display END. The OFF key is also used to exit the instrument setup menu or range selection menu. Any changes made prior to exit will be saved.

4.2 Bottle connections

Each bottle position/channel has the applicable tube numbered with a plastic sleeve. The bottle positions are numbered 1 though 6 with number 1 in the back left corner of the chassis. Use the channel selection keys as a guide.

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