Six-Channel Oxygen Meter (Model 929)
Part of a complete system for replicate dissolved oxygen measurements and multi-chamber respirometry experiments. Data acquisition and analysis software and computer hardware interface included. Applications include closed chamber respirometry, flow respirometry, dissolved oxygen monitoring.
- Use of 6 electrodes allows replicates in experiments
- Almost any oxygen tension or concentration units can be selected
- All setup procedures, including calibration, carried out on-screen
- Chart recorder-type display
- Facility to insert markers during recording if required
- Analysis is rapid and accurate, calculating normalised respiration rates if required
Part of the RS-650 System.
The 929 Six-Channel Oxygen Meter is designed for replicate (i.e. up to six) measurements of dissolved oxygen, together with data recording and analysis by computer. It's also ideal for multi-chamber repsirometry experiments, using either closed chamber or flow cell respirometry systems.
The main components of the 929 include:
- 929 Interface; Connects the electrodes to the computer
- Software; Compatible with Microsoft Windows
- Up to six 1302 Oxygen Sensors (purchased separately)
Closed cell respirometry is performed using either one RC-650 six electrode respirometer, or up to six each of the MT-200, RC-300, or RC-350 single cells. Respirometers and single cells purchased separately.
The 929 Six-Channel Oxygen Meter was developed to combine the precision of the established 782 Dual-Channel Oxygen Meter with the ability to run replicate experiments, and to monitor and analyze the results by computer. The 929 is particularly valuable in respirometry experiments since the software has been written to accommodate the large range of procedures and recording units which are used by different research workers. Use of this system will result in considerable time saving in both respiration experiments and in dissolved oxygen monitoring situations. All operations are controlled from the computer screen, and output of recordings in chart recorder format to a printer is available.
Logging of data by the 929 System is carried out automatically. The whole experiment is conducted on screen, from set-up right through to tabulation of normalized respiration rates. Results can be copied to other Windows programs (e.g. spreadsheet) for graphical display or statistical analysis. For those who would desire a hard copy output, the facility to print the screen traces to a color printer is available.
The 929 interface contains the electronics needed to supply a controllable stable bias voltage (for to up to 6 oxygen electrodes), amplify the resulting signal currents, convert the analog current signals into digital values and send these digital values to the computer. The interface is microprocessor-based and incorporates the latest integrated circuits. The input amplifiers are highly sensitive, high impedance, military specification devices and the A/D converters are 16/22 bit sigma delta devices which provide integral filtering of noise. The power supply employs a wide input switched-mode regulator and can use power sources from 110 volts to 250 volts with no adjustment. To enhance ripple rejection, the interface will only operate on a 50 or 60 Hz supply.
The interface has only one front panel control, the POWER switch, which is disabled while measurements are being made. It has an illuminated text display to inform the user of all operations carried out under control of the computer, including a continuous readout of input oxygen values. The interface provides the bias voltage to the electrodes, amplifies the signal from them, carries out A/D conversion, provides signal averaging and communicates with the software resident in the computer.
The software package includes experiment set-up; data recording; and data analysis. When the software is used for monitoring dissolved oxygen, oxygen values at flagged or set points can also be directly transferred to the Results and Reports page.
The program has been written so that it is user-friendly and quick to learn. It can be used for closed cell respirometry (using the MT-200, RC-300, RC-350 or RC-650), flow respirometry (using the FC-100 or MC-100), or for monitoring dissolved oxygen (using any of the above). When used for respirometry experiments, it follows the familiar logical sequences of operations, from electrode calibration to recording and analysis.
The setup screen is used for entering all of the details which the computer needs in order to record in the correct units, and to express the respiration rate, normalised to biomass units if required, in the desired units. All experimental details entered here are transferred through to the final calculated results report page. During setup, the cell volumes (for closed cell) and flow rate, electrode positioning (for flow respirometry), temperature of the experiment, scrolling speed of the traces during recording, and the instruction to print the recording screen to printer (if hard copy is required) are all entered. Many of these will not change from one experiment to the next, and it is only necessary to enter changes.
Clicking the 'Start' button initiates the recording process, and traces the data scroll across the screen. If substrates, inhibitors or other solutions require to be added during the run, the position where this occurs can be recorded with a flag, and the nature of the addition is recorded on a drop down menu. At the termination of the experiment, the data are saved to a data file, and may be analyzed straight away if required.
The data file and recorded traces, and event marker flags are recalled to the screen. If the recording has exceeded one screen width, it can be contracted to fit the screen, if required. Alternatively it is possible to scroll along long recording traces. Selector lines may be dragged to enclose specific parts of the trace. Thus if the traces show both control respiration and changed respiration after adding a solution, the selector lines would be dragged to the control rate first and then to the changed rates.
In each case respiration rates (normalized if so designated) are calculated automatically by clicking the 'Calculate' button. The calculated rates are tabulated, together with the experimental details entered during Setup, on the report page. The results may be exported to a spreadsheet, word processing or statistics package. The Analysis screen and the Report page may be printed, if required.
When the software is used for dissolved oxygen monitoring, the Analysis screen displays the recorded traces and the oxygen values at flagged points or at set times can be transferred to the Results and report page. The program requires a computer with a minimum specification of: Pentium processor, 1 free serial port, 128 Mb RAM, Windows 95 or later and 4 MB hard disk space. A comprehensive Instruction Manual is also supplied.
|Resolution with 1302 Oxygen Sensor||0.1% of air-saturated water|
|Polarizing Voltage||650 mV (anode connected to ground)|
|Power Requirements||100 to 250 VAC, 50/60 Hz|
|Computer requirements||Windows PC, USB port, with Windows 7 64 bit or earlier; 4 MB of hard disk space and at least 64 MB of RAM|
|Dimensions||275 x 258 x 117 mm (11 x 11 x 4.5 in)|