HI-2790B Calibration Comparison System User Manual
ETS-Lindgren Inc. reserves the right to make changes to any products herein to improve functioning or design. Although the information in this document has been carefully reviewed and is believed to be reliable, ETS-Lindgren does not assume any liability arising out of the application or use of any product or circuit described herein; nor does it convey any license under its patent rights nor the rights of others. All trademarks are the property of their respective owners.
Table of Contents Notes, Cautions, and Warnings ................................................ v General Safety Considerations ................................................ v 1.0 Introduction .......................................................................... 7 General Description .................................................................................... 7 HI-2790B Calibration Comparison System Block Diagram .................. 8 ETS-Lindgren Product Information Bulletin ...............
8.2 Daily Check......................................................................................... 35 8.3 30-Day Constancy Check ................................................................... 36 8.4 Repair of Survey and Calibration Instruments ..................................... 37 8.5 Annual Calibration and Periodic Calibration ........................................ 37 9.0 Specifications ..................................................................... 39 Appendix A: Warranty ..........
Notes, Cautions, and Warnings Note: Denotes helpful information intended to provide tips for better use of the product. Caution: Denotes a hazard. Failure to follow instructions could result in minor personal injury and/or property damage. Included text gives proper procedures. Warning: Denotes a hazard. Failure to follow instructions could result in SEVERE personal injury and/or property damage. Included text gives proper procedures.
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1.0 Introduction The ETS-Lindgren HI-2790B Calibration Comparison System is an instrument calibration comparison system that can be used by microwave oven manufacturers to comply with the Center for Devices and Radiological Health (CDRH) requirements as outlined in Guide for Preparing Reports on Radiation Safety of Microwave Ovens, dated March 1985.
An HI-1710 Microwave Survey Meter to serve as a Local Calibration Reference (HI-1710 LCR). Note: For maximum accuracy and traceability, the HI-1710 LCR and the HI-2623 Probe/Preamp Assembly must be used together as a single unit. The HI-2623 assembly should not be used for general oven leakage testing or any other purpose. The HI-1710 LCR and the HI-2790B Power/Control Module are mounted on top of the cabinet toward the rear edge.
ETS-Lindgren Product Information Bulletin See the ETS-Lindgren Product Information Bulletin included with your shipment for the following: Warranty information Safety, regulatory, and other product marking information Steps to receive your shipment Steps to return a component for service ETS-Lindgren calibration service ETS-Lindgren contact information www.ets-lindgren.
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2.0 Maintenance CAUTION: Before performing any maintenance, follow the safety information in the ETS-Lindgren Product Information Bulletin included with your shipment. WARNING: Maintenance of the HI-2790B and HI-1710 LCR is limited to external components such as cables or connectors. Clean the exterior of the cabinet using a damp cloth and mild cleaner. Always unplug the unit before cleaning. Keep the interior of the cabinet free of any foreign objects. Warranty may be void if the housing is opened.
3. Replace the blown fuse with the spare fuse. 4. Slide the fuse drawer back into the module. Make sure that the drawer snaps securely into its locked position. Service Procedures CONTACTING ETS-LINDGREN Note: Please see www.ets-lindgren.com for a list of ETS-Lindgren offices, including phone and email contact information. SENDING A COMPONENT FOR SERVICE For the steps to return a system or system component to ETS-Lindgren for service, see the Product Information Bulletin included with your shipment.
3.0 Setup CAUTION: Before connecting any components, follow the safety information in the ETS-Lindgren Product Information Bulletin included with your shipment. Connecting Components See HI-2790B Calibration Comparison System Block Diagram on page 8 for a description of connections. 1. Connect the HI-2790B Power/Control Module and the HI-1710 Microwave Survey Meter (HI-1710 LCR) to the mains power supply.
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4.0 Operation CAUTION: Before placing into operation, follow the safety information in the ETS-Lindgren Product Information Bulletin included with your shipment. Description of Controls The following controls on the HI-2790B Power/Control Module allow the control, adjustment, and monitoring of all functions of the HI-2790B Calibration Comparison System. Control Function POWER Turns unit on and off. RF Turns RF power to the test chamber on and off. RF LEVEL Adjusts power level up and down.
Operation of Controls Operation Screen 1. Turn on power to the HI-1710 LCR and the HI-2790B Power/Control Module. The two modes of the Power/Control Module that display are Operating and Status. When initially turned on, the product screen displays. The version screen displays, and then the RF power operating mode screen displays. 2. In Operating mode, the home (initial) screen is RF power.
Operation Screen Net or Difference Power—DIF power is the difference between the forward and reflected power values, and represents the net power delivered to the chamber. 3. To switch to Status mode, press the DISP SELECT key. The following parameters are displayed in the Status mode: Internal temperature +10.5 VDC system power supply voltage +6 VDC system power supply voltage +5 VDC system power supply voltage RF output frequency 4.
Error Messages Note: There are no user serviceable error messages. The HI-2790B Power/Control Module continually monitors the power supply voltages, the forward and reflected power levels, and the phase lock loop. If any of these readings fall outside the correct operating range of the unit, the unit will turn off the RF power and display one of the following messages: 10.5V LO 10.
Establishing a Reference Field 4.1.1 Position the HI-1710 LCR sensing probe in the probe holder with the rear of the probe head firmly seated against the end of the holding fixture. Insert the end of the probe handle into the probe holder and tighten the thumbscrew. 4.1.2 Select the 0–2 mW/cm2 range, FAST response (Filter 2), and the PEAK HOLD selection to OFF (PEAK HOLD LED is not lit). 4.1.3 Turn on the RF switch and adjust the RF LEVEL until approximately 1.00 mW/cm2 is displayed on the HI-1710 LCR.
4.1.10 Check the system field level at 1 mW/cm2 by placing the HI-1710 LCR probe in the chamber and aligning the probe at its midpoint reading. 4.1.11 Remove the HI-1710 LCR probe and place it in its holder on top of the system. 4.1.12 This ends the setup procedure for the HI-2790B system. The information logged in step 4.1.9 on page 19 must be reviewed to make sure that the HI-2790B system remains stable.
Recording Data Record the following data in a permanent log similar to the example HI-2790B Operational Log on page 33. 4.2.1 Each log should identify the HI-2790B Power/Control Module serial number and the serial numbers of the HI-1710 LCR and HI-2623 Probe/Preamp Assembly. 4.2.2 Date. 4.2.3 Power/Control Module FWD, REF, DIFF, and RF Power readings (at 1.0 mW/cm2). 4.2.4 HI-1710 LCR bias voltage. 4.2.5 HI-1710 LCR ellipticity values (maximum, minimum, and mean). 4.2.
Microwave Oven Survey Instrument Daily Ellipticity Check 4.3.1 Zero the instrument to be checked, making sure the access door is closed or the RF switch is off. Insert the probe of the instrument to be measured into the HI-2790B probe holding fixture. Make sure the probe is properly located against the stop on the holding fixture. Set the scale of the instrument to that used for compliance testing (usually the 0-2 mW/cm2 range). 4.3.
Calibration Comparison 4.5.1 With the Power/Control Module RF POWER set to OFF, check that the instrument being checked is properly zeroed. Turn the RF Power switch on and check that the indicated RF POWER is 1.0 mW/cm2 as established in step 4.1.9 on page 19. Rotate the probe slowly through one full revolution (360 degrees) and record the maximum and minimum readings. 4.5.2 Add the MAX reading to the MIN reading and divide the sum by two. The result is the MEAN value. 4.5.
30-Day Comparison Requirements 24 4.6.1 No value of the MEAN reading of any instrument may be lower than 90% of the highest reading observed over a 12-month period between annual calibrations of the HI-1710 LCR. Any time the MEAN reading or ELLIPTICITY reading is outside the specified limits, that instrument must be rejected. It should be returned to the original manufacturer for repair and/or recalibration. Never attempt to adjust the calibration of an instrument.
5.0 Calibration Comparison Log 30-Day Check To make sure that microwave survey instruments are being checked in accordance with Center for Devices and Radiological Health (CDRH) guidelines, complete the Calibration Comparison Log 30 Day Check form on page 26 using the following instructions, and in conjunction with the HI-2790B Calibration Comparison System. Note: The word MEAN is used to refer to the average or center value of the polarization ellipticity reading. 5.1.
5.1.4 The person performing the test should be identified in the INITIAL column. 5.1.5 The mean readings and/or limits may be graphically displayed as desired in the chart space provided at the bottom of the log. 5.1.6 Logs for an acceptable meter and a rejected meter are shown in the example logs on pages 27 and 28. Calibration Comparison Log 30-Day Check www.ets-lindgren.
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Calibration Comparison Log 30-Day Check www.ets-lindgren.
6.0 Calibration Comparison Log 2 dB Limitation Check See the example logs on pages 31 and 32. Every 30 days review the results of the 30-day calibration comparison check on all meters, including the HI-1710 LCR. Note the highest (max) reading and the lowest (min) reading from all meters for the current 30-day check. This information can be obtained from the MAX and the MIN columns on the Calibration Comparison Log 30-day Check log for each meter. 6.1.
Calibration Comparison Log 2 dB Limitation Check www.ets-lindgren.
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Calibration Comparison Log 2 dB Limitation Check www.ets-lindgren.
7.0 HI-2790B Operational Log A permanent log similar to the following HI-2790B Operational Log should be maintained for the HI-2790B Calibration Comparison System. See Recording Data on page 21 for instructions to complete the form. www.ets-lindgren.
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8.0 CDRH Section 8 Report Guidelines Following is a suggested set of answers to Section 8 of the Center for Devices and Radiological Health (CDRH) Guide for Preparing Reports on Radiation Safety of Microwave Ovens. 8.1 Microwave Test Instruments (Type and Quantity) To be answered by each oven manufacturer. List the manufacturer, model number, and quantity of meters as requested. For example: ETS-Lindgren Model HI-1501, quantity: 13 8.2 Daily Check 8.2.1 Check Yes. 8.2.2 Check Yes. 8.2.3 Check Yes.
8.2.8 Check Yes. 8.2.9 Check Yes. 8.2.10 Check box and supply a sample of the daily check record for a hand-held meter and a sample print-out of the AMOSS daily sign-on log form. 8.3 30-Day Constancy Check 8.3.1 Instrument Intercomparison System Manufacturer name and model number: ETS-Lindgren Model HI-2790B RF source frequency and frequency stability: 2450 MHz, ± 0.
8.3.11 Check Yes. 8.3.12 Check Yes. 8.3.13 Check the box, enclose a copy of the 2 dB Limitation Check Log, and label it Attachment 8.3.13. 8.3.14 Check Yes. 8.3.15 Check the box, enclose a copy of the 30-day Check Log, and label it Attachment 8.3.15. 8.4 Repair of Survey and Calibration Instruments 8.4.1 All microwave survey compliance instruments are repaired and recalibrated by ETS-Lindgren. 8.4.2 Check the box and include a copy of your procedure, and label it Attachment 8.4.2. 8.4.
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9.0 Specifications Frequency: 2450 + 0.1 MHz over an ambient temperature range of 20 degrees to 24 degrees C Frequency Stability: 50 ppm/°C + 0.0025% Dynamic Range: 0.1 – 5 + mW/cm2 Plane-wave equivalent power density at probe test location. Input Power: 100 – 240 VAC 0.8 – 0.4 A max 50 – 60 Hz Fuses: 250 Volt, 1.0 Amp, Type T (5 mm x 20 mm) Output: 2450 MHz, 4 W max Do not operate without 50 ohm load.
Repeatability of Measurements: If the recommended procedures are followed, an operator can repeat measurements to plus or minus 2% (of this, plus or minus 1% will be due to the last digit uncertainty of the digital meter on the HI-1710 LCR).
Appendix A: Warranty Note: See the Product Information Bulletin included with your shipment for the complete ETS-Lindgren warranty for your HI-2790B Calibration Comparison System. Duration of Warranties All product warranties, except the warranty of title, and all remedies for warranty failures are limited to one year. Product Warranted Duration of Warranty Period HI-2790B Calibration Comparison System 1 Year www.ets-lindgren.
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Appendix B: Declaration of Conformity Factory Issued by ETS-Lindgren L.P. ETS-Lindgren L.P. 1301 Arrow Point Drive Cedar Park, TX, USA 78613 1301 Arrow Point Drive Cedar Park, TX, USA 78613 ETS-Lindgren L.P.
EN 61326:1997 (Amendment A1: 1998) Electrical equipment for measurement, control, and laboratory use – EMC requirements EN 61326-1:1997 Electrical equipment for measurement, control, and laboratory use—EMC requirements AUTHORIZED SIGNATORIES The authorizing signatures on this Declaration of Conformity document authorize ETS-Lindgren L.P. to affix the CE mark to the indicated product. CE marks placed on these products will be distinct and visible.
