7102 Micro-Bath User's Guide PN 3729328 December 2013 © 2013 Fluke Corporation. All rights reserved. Specifications are subject to change without notice. All product names are trademarks of their respective companies.
LIMITED WARRANTY AND LIMITATION OF LIABILITY Each Fluke product is warranted to be free from defects in material and workmanship under normal use and service. The warranty period is one year and begins on the date of shipment. Parts, product repairs, and services are warranted for 90 days.
Table of Contents Chapter 1 Title Page Before You Start .................................................................................. 1-1 1.1 Symbols Used ................................................................................. 1-1 1.2 Safety Information ........................................................................... 1-2 1.2.1 Warnings ............................................................................... 1-2 1.2.2 Cautions ............................................
7102 User's Guide 7 Parts and Controls .............................................................................. 7-1 7.1 Front Panel ...................................................................................... 7-1 7.2 Back Panel ...................................................................................... 7-2 7.3 Accessories ..................................................................................... 7-3 7.3.1 Transport/Pour Access Lid .....................................
Contents (continued) 9.8.1 Operating Parameters .............................................................. 9-8 9.8.1.1 High Limit ........................................................................... 9-9 9.8.1.2 Stir Speed .......................................................................... 9-9 9.8.2 Serial Interface Parameters ...................................................... 9-9 9.8.2.1 Baud Rate .......................................................................... 9-10 9.8.2.
7102 User's Guide iv
List of Tables Table Title Page 1. 2. 3. 4. 5. International Electrical Symbols ................................................................ Specifications ............................................................................................ Table of Various Bath Fluids ..................................................................... Nominal Stirrer Motor SettingsWith Different Liquids ................................ Controller Communications Commands ..................................
7102 User's Guide vi
List of Figures Figure Title Page 1. 2. 3. 4. 5. 6. 7. 8. 7102 Front Panel ....................................................................................... 7102 Back Panel and Bottom .................................................................... Bath Lids and Lid Parts ............................................................................. Probe Basket ............................................................................................. Stir Bar ..............................
7102 User's Guide viii
Chapter 1 Before You Start 1.1 Symbols Used Table 1 lists the International Electrical Symbols. Some or all of these symbols may be used on the instrument or in this manual. Table 1.
7102 User's Guide 1.2 Safety Information Use this instrument only as specified in this manual. Otherwise, the protection provided by the instrument maybe impaired. The following definitions apply to the terms “Warning” and “Caution”. 1.2.1 • “Warning” identifies conditions and actions that may pose hazards to the user. • “Caution” identifies conditions and actions that may damage the instrument being used. Warnings Warnings To avoid personal injury, follow these guidelines.
Before You Start 1 1.2 Safety Information • Before initial use, or after transport, or after storage in humid or semi-humid environments, or anytime the instrument has not been energized for more than 10 days, the instrument needs to be energized for a “dry-out” period of 2 hours before it can be assumed to meet all of the safety requirements of the IEC 61010-1.
7102 User's Guide ELECTRICAL HAZARD • These guidelines must be followed to ensure that the safety mechanisms in this instrument will operate properly. This instrument must be plugged into an AC only electric outlet as listed in Section 3.1, Specifications. The power cord of the instrument is equipped with a three-pronged grounding plug for your protection against electrical shock hazards. It must be plugged directly into a properly grounded threeprong receptacle.
Before You Start 1.3 Authorized Service Centers 1.3 • DO NOT operate this instrument in an excessively wet, oily, dusty, or dirty environment. • The unit is a precision instrument. Although it has been designed for optimum durability and trouble free operation, it must be handled with care. • Most probes have handle temperature limits. Be sure that the probe handle temperature limit is not exceeded in the air above the instrument.
7102 User's Guide Fluke Nederland B.V. Customer Support Services Science Park Eindhoven 5108 5692 EC Son NETHERLANDS Phone: +31-402-675300 Telefax: +31-402-675321 E-mail: ServiceDesk@fluke.nl Fluke Int’l Corporation Service Center - Instrimpex Room 2301 Sciteck Tower 22 Jianguomenwai Dajie Chao Yang District Beijing 100004, PRC CHINA Phone: +86-10-6-512-3436 Telefax: +86-10-6-512-3437 E-mail: xingye.han@fluke.com.cn Fluke South East Asia Pte Ltd.
Chapter 2 Introduction The Hart Scientific 7102 Micro-Bath may be used as a portable instrument or bench top temperature calibrator for calibrating thermocouple and RTD temperature probes. The 7102 is small enough to use in the field, and accurate enough to use in the lab. With an ambient temperature of 23 °C (74 °F), calibrations may be done over a range of −5 °C to 126 °C (23 °F to 259 °F). The resolution of the 7102 temperature display is 0.01 degrees.
7102 User's Guide 2-2
Chapter 3 Specifications and Environmental Conditions 3.1 Specifications Table 2. Specifications Range −5 to 125 °C (23 to 257 °F) Accuracy ±0.25 °C Stability ±0.015 °C at −5 °C (oil, 5010) ±0.03 °C at 121 °C (oil, 5010) Uniformity ±0.02 °C Resolution 0.01 °C/F Operating Temperature 5 to 45 °C (41 to 113 °F) Heating Time 25 °C to 100 °C (77 °F to 212 °F): 30 minutes Cooling Time 25 °C to 0 °C (77 °F to 32 °F): 30 minutes Well Size 2.5" dia. x 5.
7102 User's Guide 3.2 Environmental Conditions Although the instrument has been designed for optimum durability and troublefree operation, it must be handled with care. The instrument should not be operated in an excessively dusty or dirty environment. Maintenance and cleaning recommendations can be found in the Maintenance Section of this manual.
Chapter 4 Quick Start Caution: READ SECTION 6 ENTITLED BATH USE before placing the bath in service. Incorrect handling can damage the bath and void the warranty. 4.1 Unpacking Unpack the Micro-Bath carefully and inspect it for any damage that may have occurred during shipment. If there is shipping damage, notify the carrier immediately.
7102 User's Guide 4.2 Setup Caution: DO NOT operate this instrument without fluid. Place the calibrator on a flat surface with at least 6 inches of free space around the instrument. Plug the power cord into a grounded mains outlet. Observe that the nominal voltage corresponds to that indicated on the back of the calibrator. Carefully insert the probe basket into the well. Fill the well with the appropriate fluid. The set-point temperature and the number of and size of probes determine the fluid level.
Chapter 5 Installation Caution: READ SECTION 6 ENTITLED BATH USE before placing the bath in service. Incorrect handling can damage the bath and void the warranty. 5.1 Bath Environment The 7102 Micro Bath is a precision instrument which should be located in an appropriate environment. The location should be free of drafts, extreme temperatures and temperature changes, dirt, etc. The surface where the bath is placed must be level.
7102 User's Guide 5.3 Bath Preparation and Filling The 7102 Micro Bath is not provided with a fluid. Various fluids are available from Hart Scientific and other sources. Depending on the desired temperature range, any of the following fluids, as well as others, may be used in the bath: • Water (distilled) • Ethylene glycol/water • Mineral oil • Silicone oil Fluids are discussed in detail in Section 8.3.
Chapter 6 Bath Use Caution: Read before placing the bath in service The information in this section is for general information only. It is not designed to be the basis for calibration laboratory procedures. Each laboratory will need to write their own specific procedures. 6.1 General Be sure to select the correct fluid for the temperature range of the calibration. Bath fluids should be selected to operate safely with adequate thermal properties to meet the application requirements.
7102 User's Guide Warning: Some of the high temperature fluids react violently to water or other liquid mediums. For optimum accuracy and stability, allow the bath adequate stabilization time after reaching the set-point temperature. 6.2 Comparison Calibration Comparison calibration involves testing a probe (unit under test, UUT) against a reference probe.
Chapter 7 Parts and Controls The user should become familiar with the bath and its parts: 7.1 Front Panel Figure 1 on this page. Figure 1. 7102 Front Panel Controller Display – The digital display is an important part of the temperature controller because it not only displays set and actual temperatures but also displays various calibrator functions, settings, and constants. The display shows temperatures in units according to the selected scale °C or °F.
7102 User's Guide EXIT – Used to exit a function. Any changes made to the displayed value are ignored. Holding the EXIT button for approximately 0.5 seconds exits back to the main display. 7.2 Back Panel Figure 2 on next page. Power Cord – Underneath the calibrator is the removable power cord inlet that plugs into an IEC grounded socket. Figure 2.
Parts and Controls 7.3 Accessories 7 Power Switch – The power switch is located on the power entry module (PEM). The PEM also houses the fuses and the dual voltage selector. The PEM allows the unit to be field switchable for 115 VAC ( ±10 %) or 230 VAC ( ±10 %) operation. Serial Port – A DB-9 male connector is present for interfacing the calibrator to a computer or terminal with serial RS-232 communications.
7102 User's Guide 7.3.2 Access Cover (Optional) An aluminum access cover (Figure 3) is available for optimum stability. Holes should be drilled in the access cover to allow insertion of the probes into the well. The holes must be within the guide ring for the probes to fit into the probe basket. Warning: DO NOT install an access cover without holes (like the optional cover) onto a bath that is energized. Dangerous pressures may result from fluids vaporizing. 7.3.
Chapter 8 General Operation 8.1 Changing Display Units The 7102 can display temperature in Celsius or Fahrenheit. The temperature units are shipped from the factory set to Celsius. To change to Fahrenheit or back to Celsius there are two ways: 1. Press “SET” and “UP” simultaneously. This will change the display units. 2. Press the “SET” key three times from the temperature display to show Un = C or • Press the “UP” or “DOWN” key to change units. • Press “SET” to store changes. 8.
7102 User's Guide 8.3 Bath Fluid Many fluids work with the 7102 bath. Choosing a fluid requires consideration of many important characteristics of the fluid. Among these are temperature range, viscosity, specific heat, thermal conductivity, thermal expansion, electrical resistivity, fluid lifetime, safety, and cost. 8.3.1 Temperature Range One of the most important characteristics to consider is the temperature range of the fluid.
General Operation 8.3 Bath Fluid 8 8.3.5 Thermal Expansion Thermal expansion describes how the volume of the fluid changes with temperature. Thermal expansion of the fluid used must be considered since the increase in fluid volume as the bath temperature changes may cause overflow. Excessive thermal expansion may also be undesirable in applications where constant liquid level is important. Many fluids including oils have significant thermal expansion. 8.3.
7102 User's Guide 8.3.10 Commonly Used Fluids Below is a description of some of the more commonly used fluids and their characteristics. 8.3.10.1 Water (Distilled) Water is often used because of its very low cost, availability, and excellent temperature control characteristics. Water has very low viscosity and good thermal conductivity and heat capacity which makes it among the best fluids for control stability at low temperatures.
General Operation 8.3 Bath Fluid 8 8.3.11.1 Limitations and Disclaimer The information given in this manual regarding fluids is intended only to be used as a general guide in choosing a fluid. Though every effort has been made to provide correct information we cannot guarantee accuracy of data or assure suitability of a fluid for a particular application. Specifications may change and sources sometimes offer differing information.
7102 User's Guide Figure 6. Chart of Various Bath Fluids 8.3.11.2 About the Graph The fluid graph visually illustrates some of the important qualities of the fluids shown. Temperature Range: The temperature scale is shown in degrees Celsius. The fluids’ general range of application is indicated by the shaded bands. Qualities including pour point, freeze point, important viscosity points, flash point, boiling point and others may be shown.
8 General Operation 8.4 Stirring Pour Point: This represents a handling limit for the fluid. Viscosity: Points shown are at 50 and 10 centistokes viscosity. When viscosity is greater than 50 centistokes stirring is very poor and the fluid is unsatisfactory for bath applications. Optimum stirring generally occurs at 10 centistokes and below. Fume Point: A fume hood should be used.
7102 User's Guide Warning: Do not mix water and oil when exceeding temperatures of 90 °C Table 4. Nominal Stirrer Motor Settings with Different Liquids Liquid Distilled Water Stir Motor Setting 15 Temperature 5 °C to 90 °C (41 °F to 194 °F) Ethylene Glycol 15 −5 °C to 90 °C (25 °F to 194 °F) 200.05 Oil 15 −5 °C to 125 °C ( −23 °F to 258 °F) 200.10 Oil 15 25 °C to 125 °C (77 °F to 258 °F) 8.
8 General Operation 8.7 Fluid Drain 8.7 Fluid Drain The fluid may be drained from the 7102 by tightly screwing the transport/pour access lid onto the top of the bath and pouring the liquid into an appropriate container. 8.8 Temperature Controller The bath temperature is controlled by Hart Scientific’s unique hybrid digital/analog temperature controller.
7102 User's Guide 8-10
Chapter 9 Controller Operation This chapter discusses in detail how to operate the bath temperature controller using the front control panel. Using the front panel key-switches and LED display the user may monitor the well temperature, set the temperature set-point in degrees C or F, monitor the heater output power, adjust the controller proportional band, and program the calibration parameters, operating parameters, and serial interface configuration.
7102 User's Guide Figure 7.
Controller Operation 9.2 100.00C Temperature Set-point 9 Well temperature in degrees Celsius Access set-point memory 1. 25 Set-point memory 1, 25 °C currently used To change the set-point memory press “UP” or “DOWN”. 4. 125. New set-point memory 4, 125 °C Press “SET” to accept the new selection and access the set-point value. Accept selected set-point memory 9.2.2 Set-point Value The set-point value may be adjusted after selecting the set-point memory and pressing “SET”. 4 125.
7102 User's Guide 9.3 Scan The scan rate can be set and enabled so that when the set-point is changed the bath heats or cools at a specified rate (degrees per minute) until it reaches the new set-point. With the scan disabled the bath heats or cools at the maximum possible rate. 9.3.1 Scan Control The scan is controlled with the scan on/off function that appears in the main menu after the set-point function. Sc=OFF Scan function off Press “UP” or “DOWN” to toggle the scan on or off.
Controller Operation 9.4 Temperature Display Hold 9 9.4.1 Hold Temperature Display The hold feature is enabled by simply pressing the “UP” button when the temperature is displayed. The hold temperature display shows the hold temperature on the right and the switch status on the left. For the status “c” means the switch is closed and “o” means the switch is open. The status flashes when the switch is in its active position (opposite the normal position).
7102 User's Guide 9.4.4 Switch Test Example This section describes a possible application for the temperature hold feature and how the instrument is set up and operated. Suppose you have a thermal switch which is supposed to open at about 75 °C and close at about 50 °C and you want to test the switch to see how accurate and repeatable it is. You can use the temperature hold feature and the scan function to test the switch.
Controller Operation 9.7 Proportional Band 9 The heater power display is accessed in the secondary menu. Press “SET” and “EXIT” simultaneously and release. The heater power will be displayed as a percentage of full power. 100.00C Well temperature + Access heater power in secondary menu SEC Flashes 12.0 P Heater power in percent To exit out of the secondary menu hold “EXIT”. To continue on to the proportional band setting function press “EXIT” momentarily or “SET”. 9.
7102 User's Guide The proportional band width is easily adjusted from the front panel. The width may be set to discrete values in degrees C or F depending on the selected units. The proportional band adjustment is be accessed within the secondary menu. Press “SET” and “EXIT” to enter the secondary menu and show the heater power. Then press “SET” to access the proportional band. + 12.
Controller Operation 9.8 Controller Configuration 9 9.8.1.1 High Limit The High Limit Parameter adjusts the upper set-point temperature. The factory default and maximum temperature are set to 126 °C. For safety, a user can adjust the HL down so the maximum temperature set-point is restricted.
7102 User's Guide 9.8.2.1 Baud Rate The baud rate is the first parameter in the menu. The baud rate setting determines the serial communications transmission rate. The baud rate parameter is indicated by, bAUd Flashes “bAUd” and then displays the setting 2400 b Current baud rate The baud rate of the serial communications may be programmed to 300, 600, 1200,2400, 4800, or 9600 baud. Use “UP” or “DOWN” to change the baud rate value.
Controller Operation 9.8 Controller Configuration d=FULL 9 Current duplex mode setting The mode may be changed using “UP” or “DOWN” and pressing “SET”. d=HALF New duplex mode setting 9.8.2.4 Linefeed The final parameter in the serial interface menu is the linefeed mode. This parameter enables (on) or disables (off) transmission of a linefeed character (LF, ASCII 10) after transmission of any carriage-return.
7102 User's Guide 9.8.3.1 R0 This probe parameter refers to the resistance of the control probe at 0 °C. The value of this parameter is set at the factory for best instrument accuracy. 9.8.3.2 ALPHA This probe parameter refers to the average sensitivity of the probe between 0 and 100 °C. The value of this parameter is set at the factory for best instrument accuracy. 9.8.3.3 DELTA This probe parameter characterizes the curvature of the resistance-temperature relationship of the sensor.
Chapter 10 Digital Communication Interface The Micro-Bath calibrator is capable of communicating with and being controlled by other equipment through the digital serial interface. With a digital interface the instrument may be connected to a computer or other equipment. This allows the user to set the set-point temperature, monitor the temperature, and access any of the other controller functions, all using remote communications equipment. Communications commands are summarized in Table 5.
7102 User's Guide 10.1 Serial Communications The calibrator is installed with an RS-232 serial interface that allows serial digital communications over fairly long distances. With the serial interface the user may access any of the functions, parameters and settings discussed in Section 9 with the exception of the baud rate setting. 10.1.1 Wiring The serial communications cable attaches to the calibrator through the DB-9 connector at the back of the instrument.
10 Digital Communication Interface 10.1 Serial Communications 10.1.2.1 Baud Rate The baud rate is the first parameter in the menu. The display will prompt with the baud rate parameter by showing “bAUd”. Press “SET” to choose to set the baud rate. The current baud rate value will then be displayed. The baud rate of the 7102 serial communications may be programmed to 300, 600, 1200, 2400, 4800, or 9600 baud. The baud rate is pre-programmed to 2400 baud. Use “UP” or “DOWN” to change the baud rate value.
7102 User's Guide 10.2 Interface Commands The various commands for accessing the calibrator functions via the digital interfaces are listed in this section (see Table 5). These commands are used with the RS-232 serial interface. The commands are terminated with a carriage-return character. The interface makes no distinction between upper and lower case letters, hence either may be used. Commands may be abbreviated to the minimum number of letters which determines a unique command.
Chapter 11 Test Probe Calibration Note: This procedure is to be considered a general guideline. Each laboratory should write their own procedure based on their equipment and their quality program. Each procedure should be accompanied by an uncertainty analysis also based on the laboratory’s equipment and environment. For optimum accuracy and stability, allow the calibrator to warm up for 25 minutes after power-up and then allow adequate stabilization time after reaching the set-point temperature.
7102 User's Guide Caution: Never introduce any foreign material into the well. 11.2 Stabilization and Accuracy The stabilization time of the Micro-Bath depends on the conditions and temperatures involved. Typically the test well will be stable to 0.1 °C within 10 minutes of reaching the set-point temperature. Ultimate stability will be achieved 30 minutes after reaching the set temperature.
Chapter 12 Calibration Procedure Note: This procedure is to be considered a general guideline. Each laboratory should write their own procedure based on their equipment and their quality program. Each procedure should be accompanied by an uncertainty analysis also based on the laboratory’s equipment and environment. Sometimes the user may want to calibrate the bath to improve the temperature set-point accuracy.
7102 User's Guide 12.2 Calibration Procedure 1. Choose three set-points to use in the calibration of the R0, ALPHA, and DELTA parameters. These set-points are generally 40.0 °C, 95 °C, and 195.0 °C but other set-points may be used if desired or necessary. 2. Set the bath to the low set-point. When the bath reaches the set-point and the display is stable, wait 15 minutes or so and then take a reading from the thermometer.
Calibration Procedure 12.2 Calibration Procedure 12 where T1 and R1 are the measured temperature and resistance at 50.0 °C T2 and R2 are the measured temperature and resistance at 90.0 °C T3 and R3 and R are the measured temperature and resistance at 150.0 °C 12.2.
7102 User's Guide 12-4
Chapter 13 Maintenance • The calibration instrument has been designed with the utmost care. Ease of operation and simplicity of maintenance have been a central theme in the product development. Therefore, with proper care the instrument should require very little maintenance. Avoid operating the instrument in an oily, wet, dirty, or dusty environment. • If the outside of the instrument becomes soiled, it may be wiped clean with a damp cloth and mild detergent.
7102 User's Guide 13-2
Chapter 14 Troubleshooting This section contains information on troubleshooting and CE Comments. 14.1 Troubleshooting Problems, Possible Causes, and Solutions In the event that the instrument appears to function abnormally, this section may help to find and solve the problem. Several possible problem conditions are described along with likely causes and solutions. If a problem arises, please read this section carefully and attempt to understand and solve the problem.
7102 User's Guide 14-2 The instrument heats or cools too quickly or too slowly Incorrect scan and scan rate settings. The scan and scan rate settings may be set to unwanted values. Check the Scan and Scan Rate settings. The scan may be off (if the unit seems to be responding too quickly). The scan may be on with the Scan Rate set low (if unit seems to be responding too slowly). An “o” is displayed at the left of the display External switch is open.
Troubleshooting 14.2 Comments AC voltage present on the chassis 14 Use a wall plug tester to check the main power plug at the wall. Use an ohmmeter to check the continuity between the ground prong on the PEM and the chassis. If the resistance reading is greater than three ohms, there is a problem. Check the power cord for continuity on the ground prongs. If the resistance is greater than one ohm, replace the power cord. 14.2 Comments 14.2.
7102 User's Guide 14-4
