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3M

 ScanEM-C

ElectroMagnetic 

Near-Field Probe Kit

 

Model CTK015

User’s Guide

Содержание CTK015

Страница 1: ...3M ScanEM C ElectroMagnetic Near Field Probe Kit Model CTK015 User s Guide ...

Страница 2: ...if not avoided could result in death or serious injury and or property damage CAUTION Indicates a potentially hazardous situation which if not avoided may result in minor or moderate injury and or property damage NOTICE Indicates a potentially hazardous situation which if not avoided may result in property damage WARNING To reduce the risks associated with impact related injury which if not avoide...

Страница 3: ...ence and 2 this device must accept any interference received including interference that may cause undesired operation Note 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 environm...

Страница 4: ...bes for a spectrum analyzer 12 Non contact oscilloscope probes 13 Broadband field strength probe for a multimeter 15 ScanEM C as a probe 16 Analyzing the results 18 Troubleshooting 20 Common places to look for excessive emissions 20 During the design phase 21 Checking the prototype 21 Before the EMC test 21 Should things go wrong 22 Seeking help 22 EMC101 23 Why EMC 23 Near field primer 23 The val...

Страница 5: ...ield Probe Kit model CTK019 ScanEM C Kit Contents The ScanEM C Kit model CTK015 consists of One ScanEM EC probe electric field model CTM030 One ScanEM HC probe magnetic field model CTM032 One Six foot 1 8 m SMB to BNC cable model AWD001 AAA batteries Two per each probe already installed Plastic storage box model CTA015 User s Guide Optional ScanEM C Kit accesories Accessories Pack model CTA101 Inc...

Страница 6: ...M C Probes are completely self contained EM field detectors When connected to test equipment ScanEM C Probes become broadband amplified near field probes In a stand alone mode ScanEM C Probes indicate the presence and strength of an electromagnetic field by two means audio indication and an LED level bar The more LEDs that are on and the higher the pitch of the sound the stronger the electromagnet...

Страница 7: ...ly Quickly troubleshoot a product that has failed a compliance test Find EM leakage on enclosures cables and connectors Find sources of EM interference Show the presence of a high frequency signal on a trace or wire without contact Help to troubleshoot circuits and wiring Work as amplified near field probes when connected to a spectrum analyzer Work as non contact high bandwidth voltage and curren...

Страница 8: ...result The level dial is used to set the normal background level It also works as a squelch control The stronger the emission level the higher the pitch of the sound Five LEDs indicate relative field strength The LEDs can be used with or without sound SMB male connector Connects ScanEM C Probe to a spectrum analyzer oscilloscope frequency counter multimeter and other instruments Operate Button Kee...

Страница 9: ...ents with the ScanEM C Probe s antenna The test results may be meaningless and normal operation of the measured device may be influenced by parasitic capacitance introduced by the ScanEM C Probe in direct contact The ScanEM C Probe itself may be damaged as well if it is directly exposed to high voltage For the best results position the ScanEM C Probe perpendicular to the tested area This way stray...

Страница 10: ...sily differentiate which trace emits the most radiation by just rotating the ScanEM HC Probe around its longest axis see illustration below The ScanEM HC Probe will show the strongest readings when its coil is parallel to the offending wire Stand Alone Operation In stand alone mode the ScanEM C Probe is completely self sufficient and requires nothing else to operate Quick Set Up Hold the ScanEM C ...

Страница 11: ...proximity to the product Setting the Level Dial The Level dial sets the reference level for field strength measurements The sensitivity of the ScanEM C Probe stays the same regardless of the position of the Level dial Figure A If you let go of the Operate button and then press it again you will not need to readjust the level Set the Level dial so that when the antenna is pointed away from the test...

Страница 12: ...a probe only Use Level settings of one and above in stand alone operation Level Dial Numbers Î Î The numbers from zero to nine on the Level dial do not refer to any specific field strength nor do they signify a preset spacing in field strength between any two numbers These numbers are put there for convenience so the user can refer to them when recording relative field strength You can use these n...

Страница 13: ...ED just turned On Figure B is provided for reference only Specification is subject to change without notice Operation as a Probe 1400 1200 1000 800 600 400 200 0 Green Yel 1 Yel 2 Red 1 Red 2 LEDs m V m relative CAUTION UNLIKE SOME PASSIVE PROBES THE SCANEM C PROBE IS NOTA REVERSIBLE DEVICE DO NOT SUPPLYA SIGNAL INTO ITS OUTPUT IT CAN PERMANENTLY DAMAGEYOUR SCANEM C PROBE Basics The ScanEM C Probe...

Страница 14: ...ting any influence on the output signal Do not load the ScanEM C Probe s output with less than 50 Ohms load such as connecting it in parallel to the inputs of a spectrum analyzer and 50 Ohms input of an oscilloscope This will not damage the ScanEM C Probe but its performance will be reduced Though the ScanEM C Probe has a wide dynamic range a very strong field may overload it This may result in ha...

Страница 15: ...e counterpart at lower frequencies Avoid overloading the probes with a very strong field it may induce distortions in the ScanEM C Probe amplifiers The ScanEM EC Probe for example begins to overload at field strengths of approximately 4 V m Non Contact Oscilloscope Probes When connected to an oscilloscope the ScanEM C Probe becomes an extremely broadband non contact probe which is a great diagnost...

Страница 16: ... their bandwidth Probes have 60 100 or 250 MHz bandwidth Cost for higher frequency probes is prohibitively high With today s high speed circuits low bandwidth tools may easily miss nanosecond long transients leaving engineers to wonder why their circuits behave the way they do The bandwidth of the 3M ScanEM EC Electromagnetic Near Field Probe is at least 2 GHz outperforming most any oscilloscope p...

Страница 17: ...r set to Volts DC typical scale of 2 V You will need a BNC to banana plug adapter Set the Level dial to zero left most position In the absence of the electromagnetic field the multimeter should show 0V Should the multimeter display any other voltage reading use it as the correction factor to any further field measurements You can characterize the ScanEM C Probe s output using a GTEM cell and then ...

Страница 18: ...ring the field strength on both sides of the shield also helps to evaluate shielding The ScanEM C Probes and a multimeter can be used to check the quality of applied shielding and gaskets in production A quality control inspector can be supplied with the maximum allowed DC voltage at critical points Locating Defective Components Often one doesn t need a spectrum analyzer in order to locate malfunc...

Страница 19: ...cuits crystals or high impedance circuits anywhere where direct contact with the circuit disrupts its normal operation Locating Bad Connections The ScanEM C Probe can help in locating bad connections and broken traces by showing sharply different radiation levels and patterns before and after the connection in question Identifying Defective ICs and Other Components Quite often it is difficult to i...

Страница 20: ...n places where high frequency signals are not normally expected i e AC power lines This happens because high frequency signals produced elsewhere ride on these lines and generate an electromagnetic field Many low frequency signals contain a sufficient amount of high frequency harmonics for the ScanEM C Probe to detect If any of these non sinewave signals are generated by your equipment it may be n...

Страница 21: ...in the early stages of development where it is not yet clear what frequency will be of concern the 3M ScanEM C Electromagnetic Near Field Probe will prove to be quick and effective In some cases the ScanEM C Probe s own indication may actually do a better job than a spectrum analyzer in searching for the highest emission levels since the spectrum analyzer won t provide a total signal level It is d...

Страница 22: ...cts as an antenna Pay special attention to how the EM signals get to the cable During the Design Phase This is the time to ensure agency compliance for your product at the lowest cost and with minimum impact on your schedule The 3M ScanEM C Electromagnetic Near Field Probe can help you do the following Check your first fully or even partially working PCB assembly for hot EMI areas Look at the sche...

Страница 23: ...d above Make sure that you identify the hot spots Prepare remedies to take with you to the compliance lab i e shielding materials in case your product has trouble passing Don t forget to take your 3M ScanEM C Electromagnetic Near Field Probes with you Should Things Go Wrong Knowledge of where the EMI hot spots are is your most powerful tool in countering excessive emission levels Seeking Help If y...

Страница 24: ...th many cases of conducted emission where the cable infected with the conducted radiation becomes an antenna and in turn produces radiated emission Near Field Primer The measurements done for agency approval are performed at a distance of three to ten meters At these distances the nature of the electromagnetic field is determined by the source and the distance from the source As the test antenna g...

Страница 25: ...liance test do not help in locating the source of a problem should one exist Near field measurements are the only way to pinpoint sources of offensive radiation But how good and reliable are these tests and how does one interpret their results Since near field readings are greatly dependent on the geometry of the source and its properties any attempt to provide correlation between near field and f...

Страница 26: ... of interest to those engineers used to precision in measurements The answer is simple a near field test regardless of the test equipment used provides only relative results The near field test can show where the emission is stronger and where it is weaker and what type of field is dominant i e what specifically is causing it The 3M ScanEM C Electromagnetic Near Field Probes can locate the source ...

Страница 27: ...batteries as needed Keep ScanEM C Probes in the protective case when not in use Changing Batteries ScanEM C Probes come with the batteries installed Normally they should last several months Each ScanEM C Probe takes two AAA alkaline batteries You will need to change batteries If LEDs are getting dim and or the overall performance of the ScanEM C Probe deteriorates At least once a year If you are n...

Страница 28: ...e SMB connector on the back of the unit Do not take the nut completely off Holding both halves of the ScanEM C Probe as a single piece flip it over face up Gently remove the top half of the enclosure Carefully remove the old batteries and discard them Install new batteries Observe correct polarity Do not touch internal parts other than the batteries and the battery holder Close the case and replac...

Страница 29: ...emission level may be too high the ScanEM C Probe could be confused if high level emissions are coming from the sides and you are trying to locate a lower level emission spot in the middle Try to increase the background level adjust the Level dial Make sure that the ScanEM C Probe is perpendicular to the surface of the tested area Sometimes EM fields change with time depending on what is going on ...

Страница 30: ...red Operate button is pressed continuously while you are conducting your test Rotate the Level dial until the lights come on Check the batteries follow instructions for replacement The ScanEM C Probe produces warbled sound Quite often electromagnetic emissions change with time depending on what is going on in a circuit i e peripheral access The ScanEM C Probe may demodulate this signal just like a...

Страница 31: ...question as close as possible without touching Look and listen for any changes The higher the pitch of the sound and the more LEDs that are on the greater the strength of the electromagnetic field Amplified Probe for Use With Other Test Equipment Plug the SMB small connector of the supplied cable into the connector on the back of the ScanEM C Probe and the BNC big connector into the INPUT of your ...

Страница 32: ...V m 20 dB mA AC Load min 50 Ohms 50 Ohms AC Output Range into 50 Ohms load 0 1 Vp p 0 1 Vp p AC Output Resistance 60 kOhms 60 kOhms AC Output Range 1MOhm load 0 2 V max 0 2 V max Indication 5 LED color level bar 5 LED color level bar Connector SMB SMB Dimensions approx 6 18 x 1 21 x 0 76 6 18 x 1 21 x 0 76 Weight approx 2 25 oz 65 g 2 25 oz 65 g Batteries 2 AAA included 2 AAA included Specificatio...

Страница 33: ...31 ...

Страница 34: ...ent any product is proven not to conform with 3M s Regulatory Information Sheet then 3M s entire liability and buyer s exclusive remedy will be at 3M s option either i replacement of product with a conforming product or ii refund of the purchase price paid by buyer for each non conforming product within a reasonable time after written notification of said non conformance and return of said product...

Страница 35: ... resistors 电阻电镀部 Plating in resistors 连接器 Connector 三极管 Transistor 电感器 Inductor 电磁干扰滤波器 EMI filter 装置的焊接部 Solder in instrument IC焊接部 Solder in IC 表示该有毒有害物质在该部件所有均质材料中的含量均在SJ T11363 2006 标准规定的限 量要求以下 Indicates that this hazardous substance contained in all of the homogeneous materials for this part is below the limit requirement in SJ T11363 2006 表示该有毒有害物质至少在该部件的某一均质材料中的含量超出SJ T11363 2006 标准 规定的限量要...

Страница 36: ... contrary statements contained on your purchase order shall have no force or effect unless expressly agreed upon in writing by an authorized officer of 3M Warranty Limited Remedy Limited Liability This product will be free from defects in material and manufacture for a period of one 1 year from the time of purchase 3M MAKES NO OTHER WARRANTIES INCLUDING BUT NOT LIMITED TO ANY IMPLIED WARRANTY OF M...

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