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6725
User Manual
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Parr Instrument 6725 User Manual

Operating Instruction Manual 592M
6725
Semi-micro Oxygen Bomb Calorimeter
Operating Instruction Manual
For models produced after November 2010
TABLE OF CONTENTS
TABLE OF CONTENTS ................................................................................................ 1-1
PREFACE......................................................................................................................1-1
Scope.........................................................................................................................1-1
Explanation of Symbols..............................................................................................1-2
Safety Information......................................................................................................1-2
Intended Usage..........................................................................................................1-3
General Specifications...............................................................................................1-3
Environmental Conditions..........................................................................................1-3
Provisions for Lifting and Carrying.............................................................................1-3
INSTALLATION.............................................................................................................2-1
Power Connection......................................................................................................2-1
Oxygen Tank Installation............................................................................................2-2
Motor Installation........................................................................................................2-2
Thermistor Probe Installation.....................................................................................2-2
Communication Connections.....................................................................................2-3
Printer Connections....................................................................................................2-3
Balance Connections.................................................................................................2-3
Mettler 011/012 Interface...................................................................................................2-4
Sartorious Interface...........................................................................................................2-4
Generic Interface................................................................................................................2-4
Bar Code Port ............................................................................................................2-5
Computer Connections ..............................................................................................2-5
QUICK START...............................................................................................................3-1
OPERATION..................................................................................................................4-1
Menu System.............................................................................................................4-1
Menu Keys.................................................................................................................4-1
Control Keys...............................................................................................................4-1
Programming..............................................................................................................4-2
Default Settings..........................................................................................................4-2
Performing an analysis...............................................................................................4-3
Manual Test Sequencing.....................................................................................................4-4
Automatic Test Sequencing.................................................................................................4-6
MENU DESCRIPTIONS.................................................................................................5-1
Main Menu .................................................................................................................5-1
Calorimeter Operation Menu......................................................................................5-1
Temperature vs. Time Plot.........................................................................................5-2
Temperature Plot Setup Menu...................................................................................5-2
Operating Controls Menu...........................................................................................5-3
Spike Controls............................................................................................................5-4
Program Information and Control Menu.....................................................................5-5
Calibration Data and Controls Menu..........................................................................5-7
Thermochemical Corrections Menu.........................................................................5-10
Standardization Correction.......................................................................................5-10
Determination Correction.........................................................................................5-11
Calculation Factors Menu ........................................................................................5-12
Net Heat/Dry Heat Factors.......................................................................................5-13
Data Entry Controls Menu........................................................................................5-13
Reporting Controls Menu.........................................................................................5-15
Communication Controls Menu................................................................................5-16
File Management Menu ...........................................................................................5-17
Run Data File Manager............................................................................................5-18
Diagnostics Menu.....................................................................................................5-19
CALCULATIONS...........................................................................................................6-1
Corrections.................................................................................................................6-1
Manual vs. Fixed Corrections.....................................................................................6-2
Definitions .................................................................................................................. 6-3
Sulfur Correction........................................................................................................6-4
Acid Correction...........................................................................................................6-4
ASTM, ISO and Other Methods.................................................................................6-7
Conversion to Other Moisture Bases.........................................................................6-8
Conversion to Net Heat of Combustion......................................................................6-8
REPORTS......................................................................................................................7-1
MEMORY MANAGEMENT ............................................................................................8-1
MAINTENANCE.............................................................................................................9-1
TROUBLESHOOTING.................................................................................................10-1
Error List...................................................................................................................10-1
TECHNICAL SERVICE................................................................................................11-1
Contact Us ...............................................................................................................11-1
Return for Repair......................................................................................................11-1
PARTS LISTS..............................................................................................................12-1
Principal Assemblies in 6772 Calorimetric Thermometer ........................................12-1
Parts for the 6725 Semi-micro Calorimeter..............................................................12-2
Parts for the 1824 Oxygen Fill Connection ..............................................................12-2
DRAWINGS.................................................................................................................13-1
6772 Schematic .......................................................................................................13-1
Internal Parts View of 6772 Calorimetric Thermometer ...........................................13-2
Internal Parts View of 6772 Calorimetric Thermometer ...........................................13-3
Back Panel of 6772 Calorimetric Thermometer.......................................................13-4
External Parts View of the 6725 Semi-micro Calorimeter........................................13-5
Internal Parts Views of 6725 Semi-micro Calorimeter .............................................13-6
1824 Oxygen Filling Connection..............................................................................13-7
TABLES.......................................................................................................................14-8
Table 1 – Default Settings........................................................................................14-8
Table 2 – ISO & BSI Method Settings......................................................................14-3
TABLES.......................................................................................................................14-1
Table 1 – Default Settings.........................................................................................14-1
Table 2 – ISO & BSI Method Settings.......................................................................14-2
PREFACE
Scope
This manual contains instructions for installing and operating the Parr 6725 Semi-micro Calorimeter. For ease of use, the manual is divided into 13 chapters.
Installation Quick Start Operation Menu Descriptions Calculations Reports Memory Management Maintenance Troubleshooting Technical Service Parts Lists Drawings Tables
Subsections of these chapters are identified in the Table of Contents. To assure successful installation and operation, the user must study all instructions
carefully before starting to use the 6725 Semi-micro Calorimeter to obtain an understanding of the capabilities of the equipment and the safety precautions to be observed in the operation.
Additional instructions concerning the installation and operation of various component parts and peripheral items used with the 6725 Semi-micro Calorimeter should be made a part of these instructions. Additional instructions for the optional printer are found in the respective printer package and should be made a part of this book.
No. Description 201M Limited Warranty 492M Operating Instructions for the 1109A Semi-micro Oxygen Bombs 207M Analytical Methods for Oxygen Bombs 230M Safety in the Operation of Laboratory and Pressure Vessels 483M Introduction to Bomb Calorimetry
This manual contains detailed instructions related to oxygen bomb calorimetry, standardization of the calorimeter, combustion techniques, and thermochemical corrections.
Note: The unit of heat used in this manual is the International Table
(IT) calorie, which is equal to 4.1868 absolute joules.
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Explanation of Symbols
I
O
~
On position
Off position
Alternating Current (AC)
This CAUTION symbol may be present on the Product Instrumentation and literature. If present on the product, the user must consult the appropriate part of the accompanying product literature for more information.
ATTENTION, Electrostatic Discharge (ESD) hazards. Observe precautions for handling electrostatic sensitive devices.
Protective Earth (PE) terminal. Provided for connection of the Protective Earth (green or green/yellow) supply system conductor.
Chassis Ground. Identifies a connection to the chassis or frame of the equipment shall be bonded to Protective Earth at the source of supply in accordance with national and local electrical code requirements.
Earth Ground. Functional earth connection. NOTE: This connection shall be bonded to Protective earth at the source of supply in accordance with national and local electrical code requirements.
Safety Information
To avoid electrical shock, always:
1. Use a properly grounded electrical outlet of correct voltage and current handling capability.
2. Ensure that the equipment is connected to electrical service according to local national electrical codes. Failure to properly connect may create a fire or shock hazard.
3. For continued protection against possible hazard, replace fuses with same type and rating of fuse.
4. Disconnect from the power supply before maintenance or servicing.
To avoid personal injury:
1. Do not use in the presence of flammable or combustible materials; fire or explosion may result. This device contains components which may ignite such material.
2. Refer servicing to qualified personnel.
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Intended Usage
If the instrument is used in a manner not specified by Parr Instrument Company, the protection provided by the equipment may be impaired.
General Specifications
Electrical Ratings
115VAC, 2.0 Amps. 50/60 Hz 230VAC, 2.0 Amps, 50/60 Hz
Before connecting the calorimeter to an electrical outlet, the user must be certain that the electrical outlet has an earth ground connection and that the line, load and other characteristics of the installation do not exceed the following limits:
Voltage: Fluctuations in the line voltage should not exceed 10% of the rated nominal voltage shown on the data plate. Frequency: Calorimeters can be operated from either a 50 or 60 Hertz power supply without affecting their operation or calibration. Current: The total current drawn should not exceed the rating shown on the data plate on the calorimeter by more than 10 percent.
Environmental Conditions
This apparatus is to be used indoors. Operating: 15 °C to 30 °C; maximum relative humidity of 80% non-condensing. Installation Category II (overvoltage) in accordance with IEC 664. Pollution degree 2 in accordance with IEC 664. Altitude Limit: 2,000 meters. Storage: -25 °C and 65 °C; 10% to 85% relative humidity.
Provisions for Lifting and Carrying
Before moving the instrument, disconnect all connections from the rear of the apparatus. Lift the instrument by grabbing underneath each corner.
Periodic cleaning may be performed on the exterior surfaces of the instrument with a lightly dampened cloth containing mild soap solution. All power should be disconnected when cleaning the instrument. There are no user serviceable parts inside the product other than what is specifically called out and discussed in this manual. Advanced troubleshooting instructions beyond the scope of this manual can be obtained by calling Parr Instrument Company in order to determine which part(s) may be replaced or serviced.
Specifications
Probe type Thermistor Thermometer range 10-50 °C Resolution 0.0001 °C Absolute accuracy without calibration with calibration Repeatability, single point Linearity, 10 °C span +/- 0.002 °C Communications port Ethernet Data logging capacity 1MB (~10000 points)
+/- 0.100 °C +/- 0.0500 °C
+/- 0.002 °C
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INSTALLATION
The 6725 Semi-micro Oxygen Bomb Calorimeter is to be used indoors. It requires at least 4 square feet of workspace on a sturdy bench or table free from room drafts or radiant heat sources, (preferably in an air conditioned room providing minimal temperature change), an electrical outlet, a supply of water which is at least 1 °C cooler then room temperature and a waste drain will be required. The supply voltage must be within ± 10% of marked nominal voltage on the apparatus. The supply voltage receptacle must have an earth ground connection.
Other necessary accessories include:
• Oxygen tank of 99.5% minimum purity
• Chemical balance sensitive to 0.1 mg
• Top loading balance capable of weighing up to 1.5 kg with a sensitivity of 0.1g
Unpack the calorimeter carefully and check the individual parts against the packing list. If shipping damage is discovered, report it immediately to the delivery carrier. Handle the Dewar flask and the thermistor probe with care as these parts are fragile and easily broken.
Set the calorimeter on a bench or table in a location that is free from drafts and protected from sources of radiant heat. Temperature changes in the room should be minimal.
Power Connection
Plug the power line into any grounded outlet providing proper voltage that matches the specification on the nameplate of the Calorimetric Thermometer. The calorimeter will draw approximately 100 watts of power. Grounding is very important not only as a safety measure, but also to ensure satisfactory controller performance. If there is any question about the reliability of the ground connection through the power cord, run a separate earth ground wire to the controller chassis.
Turn the power switch to the on position. After a short time, the Parr logo will appear on the LCD display followed by a running description of the instrument boot sequence. When the boot sequence is complete, the 6772 Calorimetric Thermometer Main Menu is displayed.
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Figure 1
6772 Calorimetric Thermometer Back Panel
493E Plug
with 3280HC Retainer installed to insulate from live circuits when no motor is attached.
Oxygen Tank Installation
Install the oxygen tank according to the manufacturer’s recommendations. Unscrew the protecting cap and inspect the threads on the outlet nipple to be sure they are clean and in good condition; attach the 1824 Oxygen Filling Connection to the outlet nipple and tighten the union nut with a wrench.
Motor Installation
Attach the motor cord to the rear of the calorimeter case using the mounting screws provided for safety purposes. Set the cover with its attached stirring shaft onto the stainless steel air can; drop the geared drive belt over the motor and stirrer pulleys. The drive system should run freely. Although the belt may appear to be unusually loose, it is intended to operate under light tension to minimize friction in the stirrer bearing. The gearing on the belt and pulleys will prevent slippage.
Thermistor Probe Installation
Connections for two thermistor probes are located on the back of the 6772 Calorimetric Thermometer. If only one probe is to be used, connect it to the “bucket” connection. If the second probe is used, it should be inserted in the hole on the left, rear of the
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instrument. Install the thermistor in the cover opening and press the bushing firmly into place to anchor the probe in its proper position. Place the cover on the calorimeter with the orienting pin in the alignment hole. The 6772 Calorimetric Thermometer acts an ignition unit for automatically firing the bomb in the 6725 calorimeter. The ignition leads to the thermometer need to be connected to the red and black terminals marked “Ignition” on the back of the thermometer to take advantage of this feature.
Communication Connections
There is a USB connection on the rear of the 6772 to facilitate printer and balance connections.
The 6772 will also allow the user to specify the IP addresses of one or more Balance Interface devices on the network by selecting the Network Data Device menu in the Communications Controls menu. Balance Interface devices are polled from device 1 to 15 for sample and / or spike weights when the weight entry mode is set to Network.
The 6772 will also allow the user to specify the IP addresses of one or more Balance Interface devices on the network by selecting the Network Data Device menu in the Communications Controls menu. Balance Interface devices are polled from device 1 to 15 for sample and / or spike weights when the weight entry mode is set to Network.
Printer Connections
The printer type setting is on the Communication Controls Menu. The default parameters for the 6772 Calorimetric Thermometer are set up for use with the Parr 1758 Printer.
Balance Connections
The 6772 Calorimetric Thermometer supports input from the multiple balance types. Additionally, a generic input driver is provided for communications with balances that do not conform to the eight supported protocols. A new feature supported by all four balance input drivers is the ability to change the expected number of characters in the data field. The number of data characters indicated for each of the drivers, below, are default values. This feature virtually eliminates the need for balance input drivers to be re-written in the event the balance manufacturer elects to alter the output string of a balance when new models are introduced.
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The format of an unknown balance can be determined by logging the balance output to the printer attached to the Calorimetric Thermometer. Those protocols which send a command string to the balance will do so while logging is active. In order for the logging to produce meaningful results, the cable connecting the balance to the balance input port of the Calorimetric Thermometer must be correctly wired or configured. In addition, the specifics of the data frame, such as the baud rate, # of data bits, parity, # of stop bits and handshaking (if used) must be the same for both the balance and the Calorimetric Thermometer.
Mettler 011/012 Interface
The ID field must contain “S_” to indicate a stable mass. The data field contains the current mass, right justified, with a decimal point. The balance should be configured to send continuously.
Sartorious Interface
The polarity field must contain either a “+” or a space. Leading zeros in the data field are blanked, except for the one to the left of the decimal point. The stability field must contain “g_” for the Calorimetric Thermometer to accept a mass. The balance should be configured to transmit data upon receipt of the following command string: [ESC] P [CR] [LF]
Note:
The automatic data output option should not be used.
The Calorimetric Thermometer will send this command string once every few seconds after the ENTER key has been pressed during a mass entry sequence. The ENTER key should only be pressed when the mass reading is stable. However, unstable readings will be rejected and a warning will be issued. Acknowledging the warning by pressing the CLEAR ENTRY key will re-issue the command string to the balance on a periodic basis.
Generic Interface
The data field should consist of 9 numeric characters (0 through 9, +, ­and space) terminated with a carriage return (CR). Leading zeros may be blanked as spaces and are counted. Non-numeric characters are ignored and will reset the input buffer if the data field has not been filled. Any characters received after filling the data field and before the carriage return are ignored.
Field Length
ID 2 space 1 data 9 space 1 g 1 CR 1 LF 1
Field Length
polarity 1 space 1 data 8 space 1 stability 2 CR 1 LF 1
Field Length
data 8 CR 1
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Bar Code Port
The use of barcodes in the laboratory has become a highly accurate, rapid and inexpensive way to identify samples. When purchasing this feature, the user must supply Parr with the MAC address of the calorimeter (found in the Software & Hardware Info menu screen). This allows Parr to activate the feature key. In order to enable the calorimeter to use the bar code feature, the feature key needs to be entered into the instrument. Select the “Program Information and Control” key from the Main Menu. Next, select “Feature Key” and enter the feature key purchased from Parr Instrument Company into the instrument by using the touchpad. Pressing the key labeled “ABC” allows the user to switch from upper case letters, to lower case letters and finally to numerals. A CD containing all the necessary documentation and setup information for using both the scanner and the printer is provided at the time of purchase. A PC based program used for printing bar coded labels is also provided on this CD.
Computer Connections
If the 6772 Calorimetric Thermometer is to be connected to a computer, the Ethernet connection should be used. Calorimetric Thermometer test data can be transferred to an Ethernet network connected computer using the FTP File Transfer Protocol. First, you must know the IP address of the network­connected Calorimetric Thermometer. The network DHCP (Dynamic Host Configuration Protocol) server provides this address shortly after the Calorimetric Thermometer is turned on. The address can be seen on the Software & Hardware Info” screen, under Program Info and Control Menu; see the example screenshot. Users who don’t have a network infrastructure can create a simple network by connecting a router with DHCP server capability to the Calorimetric Thermometer using an ordinary CAT 5 network cable. The Calorimetric Thermometer should be connected to LAN side of the router. The PC in turn is also connected to the LAN side of the router using a similar CAT 5 cable. A D-Link 614+ router is recommended for this purpose. For this router, operated without a WAN connection, the primary DNS address of the router (WAN setup) must be set to the IP address of the router found on the LAN setup page. Other routers behave differently in the absence of a WAN connection. Providing an active upstream connection to the WAN port of most routers generally minimizes the use of any obscure setup configurations. An FTP enabled web browser can be used to access stored test data. The URL is of the following form:
ftp://root:rootroot@192.168.0.125/../flash/data/
In this case, 192.168.0.125 is the IP address of the Calorimetric Thermometer.
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The following screenshot illustrates the contents of the Calorimetric Thermometer data directory as presented by a web browser.
You can drag and drop or copy and paste test data files (with the csv suffix) from the web browser window to any convenient folder or directory on the PC.
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The Calorimetric Thermometer offers a web server service. Test reports can be viewed with a web browser using a URL of the following form.
http://192.168.0.125
Where 192.168.0.125 is the IP address of the Calorimetric Thermometer. The following screenshot illustrates the Calorimetric Thermometer status page.
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Clicking on the Config tab displays some of the configuration options available in the
6772. Changes made on this page will change the settings in the 6772.
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Clicking on the Run Data tab displays a list of reports currently in the instrument memory. Clicking on any given report will provide a display similar to the following:
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Clicking on System Info will bring up the Software and Hardware Info screen from the
6772.
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Clicking on the LCD Snapshot Page will bring up an image of the current display on the
6772. Note that this is a picture only. To operate the 6772 from a PC a Remote Feature Key must be installed. Please contact Parr Instrument Company for more details.
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Clicking on Documentation will provide links to the manual and other helpful documents. Note: a connection to the Internet is required to access the documentation.
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QUICK START
Detailed Instructions for preparing the sample and charging the 1109A Oxygen Bomb are given in Operating Instructions Manual No. 492M. Follow these instructions carefully, giving particular attention to the precautions to be observed in charging and handling the bomb. The default values of the 6772 are designed to operate with the 1341 Plain Jacket calorimeter. Note the parameter changes in the Operation section of this manual.
1. Allow at least 20 minutes for the calorimeter to warm up. The bomb parts should be wetted and then dried in the manner used at the conclusion of a test. This serves to wet all sealing parts as well as leaving the bomb with the same amount of residual water which will exist in all subsequent testing.
2. Turn on the stirrer motor switch on the 6725 calorimeter.
3. Prepare and weigh the sample to 0.0001g. Charge the oxygen bomb as described in manual 492M. Each bomb and bucket combination will have to be standardized separately and the proper energy equivalent for each set must be used when calculating the heat of combustion.
4. Fill the Dewar with water to the nearest multiple of 50 milliliters (grams) which just covers the small hole (gas inlet/outlet) on the bomb head inlet valve. This will be either 400 or 450 mL of water.
5. Attach one of the ignition wires to the central terminal on the bomb head and push it down as far as it will go. Attach the second wire to the socket provided on the bomb hanger. Set the bomb in the loop of the A67C2 bomb support and carefully lower it into the Dewar to hang from the top rim of the flask. Position the bomb so that the stirrer can operate freely without striking the bomb. Check for gas bubbles.
6. Close the calorimeter cover and turn on the stirrer motor in the Calorimeter Operation menu.
7. Select determination or standardization as appropriate on the Calorimeter Operation page, by toggling the operating mode key. The calorimeter will now prompt the operator for Bomb ID number, sample ID number, sample weight and spike weight in accordance with the instructions set into the operating controls page.
8. The thermometer will now take over and conduct the test. During the time it is establishing the initial equilibrium, it will display PREPERIOD on the status bar. Just before it fires the bomb, it will sound a series of short beeps to warn the user to move away from the calorimeter. Once the bomb has been fired, the status bar will display POSTPERIOD. The calorimeter will check to make certain that a temperature rise occurs and will then look for the final equilibrium conditions to be met. If it fails to meet either the initial or final equilibrium conditions, or if it fails to detect a temperature rise within the allotted time, the calorimeter will terminate the test and advise the user of the error.
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9. At the conclusion of the test, the calorimeter will signal the user.
10. Open the cover and remove the bomb and Dewar flask. Remove the bomb from the flask and release the residual gas pressure before attempting to remove the cap. This release should proceed slowly over a period of not less than one minute to avoid entrainment losses. After all pressure has been released, unscrew the cap; lift the head out of the cylinder and examine the interior of the bomb for soot or other evidence of incomplete combustion. If such evidence is found, the test will have to be discarded. Otherwise, wash all interior surfaces of the bomb, including the head, with a jet of distilled water and collect the washings in a beaker.
11. Remove all unburned pieces of fuse wire from the bomb electrodes; straighten and measure the combined length in centimeters. Subtract this length from the initial length of 10 centimeters. Multiply the burned length by 2.3 calories per cm (for Parr 45C10 Fuse Wire) to obtain the fuse correction. The scale on the fuse wire card can be used to obtain this value in calories by laying the unburned pieces from right to left on the card. (Alternatively a fixed correction of 1.5 calories may be entered into the calorimeter in the Thermochemical Corrections menu.)
12. Titrate the bomb washings with a standard sodium carbonate solution using methyl orange, red or purple indicator. A 0.0709N sodium carbonate solution is recommended for this titration to simplify the calculation. This is prepared by dissolving 3.76 grams of Na solutions of the same normality may be used.
13. Analyze the bomb washings to determine the sulfur content of the sample if it exceeds 0.1%. Methods for determining sulfur are discussed in Operating Instructions No. 207M.
14. At the end of the testing period, turn OFF the stirrer motor and the thermometer at the power switch.
in the water and diluting to one liter. NaOH or KOH
2CO3
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OPERATION
Menu System
All configurations and operations are handled by a menu-driven system operated from the bright touch screen display. The settings and controls are organized into ten main sections as displayed on the MAIN MENU.
Note:
Keys with a “double box” in the upper left hand corner lead to sub-menus.
Menu Keys
The controls that change the data field information in the menus will be one of the following:
1. Toggles. These data fields contain ON/OFF or YES/NO choices. Simply touching the key on the screen toggles the choice to the other option. The current setting is displayed in the lower right corner of the key.
2. Option Selection. These data fields contain a list of options. Touching the key on the screen steps the user through the available choices. The current setting is displayed in the lower right corner of the key.
3. Value Entry Fields. These data fields are used to enter data into the Calorimetric
Thermometer. Touching the key on the screen brings up a sub-menu with a key pad or similar screen for entering the required value. choices. Always clear the current value before entering a new value. Once entered the screen will return to the previous menu and the new value will be displayed in the lower right corner of the key.
4. Data Displays. Most of these keys display values that have been calculated by the Calorimetric Thermometer and are informational only. Certain ones can be overridden by the user entering a desired value through a sub-menu. The value is displayed in the lower right corner of the key.
Note:
Some keys will respond with an opportunity for the user to confirm the specified action to minimize accidental disruptions to the program and/or stored data.
Control Keys
There are five control keys which always appear in the right column of the primary displays. These keys are unavailable when they are gray instead of white.
1. Escape. This key is used to go up one level in the menu structure.
2. Main Menu. This key is used to return to the main menu touch screen from
anywhere in the menu structure.
3. Start. This key is used to start a Calorimetric Thermometer test.
4. Report. This key is used to access the test results stored in the Calorimetric
Thermometer, to enter thermochemical corrections, and to initiate a report on the display, printer or attached computer.
Some keys lead to multiple
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5. Help. This key is used to access help screens related to the menu currently displayed on the touch screen.
This key appears in the Escape key location when the main menu is displayed.
6.
This key is used to shut down the calorimeter program before turning off the power.
Programming
The program in the 6772 Calorimetric Thermometer can be extensively modified to tailor the unit to a wide variety of operating conditions, reporting units, laboratory techniques, available accessories and communication modes. In addition, the calculations, thermochemical corrections and reporting modes can be modified to conform to a number of standard test methods and procedures. Numerous provisions are included to permit the use of other reagent concentrations, techniques, combustion aids and short cuts appropriate for the user’s work.
Note:
Changes to the program are made by use of the menu structure. Any of these items can be individually entered at any time to revise the operating program.
Default Settings
The 6772 Calorimetric Thermometer is preprogrammed with default settings for use with the 1341 Plain Jacket Calorimeter. Therefore, the following parameters must be changed in the Calorimetry Parameters menu found in the Diagnostics Menu.
Correction (K) Parameters:
K1 0.5 K2 0.00040 K3 1.0 K4 0.0 K5 0.0
Blackout (B) Parameters: Mis-Fire Blackout (B2) 6 Derivative Blackout (B3) 0.5 Dynamic Blackout (B4) 6 Equilibrium Blackout (B5) 36 Dynamic Derivative Blackout (B6) 0.02 Dynamic Time Blackout (B7) 20
It is recommended that a Fixed Acid value of 1.5 be set on the Thermochemical
Corrections menu.
A more in-depth explanation of these parameters is found on the corresponding parameter group help pages. These default settings remain in effect until changed by the user. Should the user ever wish to return to the factory default settings, go to the Program Info and Control Menu, User/Factory Settings, touch Reload Factory Default Settings and YES. Non-volatile memory is provided to retain any and all operator initiated program changes; even if power is interrupted or the unit is turned off. If the unit experiences an intentional or unintentional “Cold Restart”, the controller will return to the last known settings.
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The default parameters of the 6772 Calorimetric Thermometer can be changed to guarantee that the thermometer, when cold restarted, will always be in the desired configuration before beginning a series of tests. Users who wish to permanently revise their default settings may do so using the following procedure:
• Establish the operating parameters to be stored as the user default settings.
• Go to the Program Info and Control Menu, User/Factory Settings, User Setup ID, and
enter the desired User Setup ID.
• Select Save User Default Settings
To re-load the user default setting, go to the Program Info and Control Page, User/Factory Settings, Re-load User Default Settings, and YES.
Performing an analysis
Tests can be run in a strictly manual fashion or automatically where the thermometer sequences the calorimeter through the pre and post periods. The manual sequencing approach is useful for applications where raw data is logged and subsequently analyzed, off-line. In the automatic mode, the thermometer fully sequences the test and applies real time corrections to the calorimeter temperature rise in order to correct for all systemic heat leak effects. In either case the operator must determine the appropriate temperature source for the jacket.
• Probe
• Calculated
• Fixed
For most applications the calculated Detailed instructions for preparing the sample and charging the 1109 oxygen bomb are
given in the Operating Instructions for the 1109/1109A Semi-micro Oxygen Combustion Bomb, manual 492M. Follow these instructions carefully, giving particular attention to the precautions to be observed in charging and handling the bomb.
The bomb parts should be wetted and then dried in the manner used at the conclusion of a test. This serves to wet all sealing parts as well as leaving the bomb with the same amount of residual water which will exist in all subsequent testing.
The two operating modes, (manual or automatic) are outlined below:
– This method uses an additional 1168E2 thermistor probe attached to the jacket wall to measure the actual temperature of the surroundings (at the chosen point) and the heat leak correction are based upon the actual differences between the bucket and this external jacket temperature.
– During the initial equilibrium period this method analyzes the actual heat leak rate and calculates the apparent temperature of the surroundings which would generate this rate and applies this calculated jacket temperature for the determination.
– In this method the operator determines what his jacket temperature will be and enters it into the thermometer. All heat leak corrections are then based upon this fixed jacket temperature.
method is recommended.
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