ISO-11452-3-2001.pdf

Reference number ISO 11452-3:2001(E) ©ISO 2001 INTERNATIONAL STANDARD ISO 11452-3 Second edition 2001-03-01 Road vehicles Component test methods for electrical disturbances from narrowband radiated electromagnetic energy Part 3: Transverse electromagnetic (TEM) cell Véhicules routiers Méthodes d'essai d'un équipement soumis à des perturbations électriques par rayonnement d'énergie électromagnétique en bande étroite Partie 3: Cellule à mode électromagnétique transverse (TEM) ISO 11452-3:2001(E) PDF disclaimer This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In downloading this file, parties accept therein the responsibility of not infringing Adobe's licensing policy. The ISO Central Secretariat accepts no liability in this area. 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CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.ch Web www.iso.ch Printed in Switzerland ii© ISO 2001 All rights reserved -,-,- ISO 11452-3:2001(E) © ISO 2001 All rights reservediii ContentsPage Foreword.iv Introduction.v 1Scope 1 2Normative reference1 3Terms and definitions .1 4Test conditions 1 5Test apparatus .2 6Test procedure.6 Annex A (informative) TEM cell dimensions 9 Annex B (informative) Calculations and measurements of TEM-cell frequency range.11 Annex C (informative) Installation of external components and low pass filter design13 Annex D (informative) Function performance status classification (FPSC) .16 Bibliography17 ISO 11452-3:2001(E) iv© ISO 2001 All rights reserved Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this part of ISO 11452 may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. InternationalStandardISO 11452-3waspreparedbyTechnicalCommitteeISO/TC 22,Roadvehicles, Subcommittee SC 3, Electrical and electronic equipment. This second edition cancels and replaces the first edition (ISO 11452-3:1995), which has been technically revised. ISO 11452 consists of the following parts, under the general title Road vehicles Component test methods for electrical disturbances from narrowband radiated electromagnetic energy: ?Part 1: General and definitions ?Part 2: Absorber-lined shielded enclosure ?Part 3: Transverse electromagnetic (TEM) cell ?Part 4: Bulk current injection (BCI) ?Part 5: Stripline ?Part 6: Parallel plate antenna ?Part 7: Direct radio frequency (RF) power injection Annexes A to D of this part of ISO 11452 are for information only. ISO 11452-3:2001(E) © ISO 2001 All rights reservedv Introduction Immunity measurements of complete road vehicles are generally able to be carried out only by the vehicle manufacturer, owing to, for example, high costs of absorber-lined shielded enclosures, the desire to preserve the secrecy of prototypes or a large number of different vehicle models. For research, development and quality control, a laboratory measuring method can be used by both vehicle manufacturers and equipment suppliers to test electronic components. The TEM cell method has the major advantage of not radiating energy into the surrounding environment. The method can be used for testing either the immunity of a component with the field coupling to the wiring harness or the immunity of the component alone with minimum exposure to the wiring harness. -,-,- INTERNATIONAL STANDARDISO 11452-3:2001(E) © ISO 2001 All rights reserved1 Road vehicles Component test methods for electrical disturbances from narrowband radiated electromagnetic energy Part 3: Transverse electromagnetic (TEM) cell 1Scope This part of ISO 11452 specifies transverse electromagnetic (TEM) cell tests for determining the immunity of electronic components of passenger cars and commercial vehicles to electrical disturbances from narrowband radiated electromagnetic energy, regardless of the vehicle propulsion system (e.g. spark-ignition engine, diesel engine, electric motor). The electromagnetic disturbances considered are limited to continuous narrowband electromagnetic fields. 2Normative reference The following normative document contains provisions which, through reference in this text, constitute provisions of this part of ISO 11452. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based on this part of ISO 11452 are encouraged to investigate the possibility of applying the most recent edition of the normative document indicated below. For undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain registers of currently valid International Standards. ISO 11452-1, Road vehicles Component test methods for electrical disturbances by narrowband radiated electromagnetic energy Part 1: General and definitions. 3Terms and definitions For the purposes of this part of ISO 11452, the terms and definitions given in ISO 11452-1 apply. 4Test conditions The upper frequency range limit of the TEM cell is a direct function of the TEM cell dimensions. For testing automotive electronic systems, a 0,01 MHz to 200 MHz TEM cell should be used. See annex A for suggested cell dimensions. The user shall specify the test severity level or levels over the frequency range. See annex D for suggested test severity levels. -,-,- ISO 11452-3:2001(E) 2© ISO 2001 All rights reserved Standard test conditions shall be those given in ISO 11452-1 for the following: ?test temperature; ?supply voltage; ?modulation; ?dwell time; ?frequency step sizes; ?definition of test severity levels; ?test-signal quality. 5Test apparatus 5.1TEM cell The TEM cell used for this test is a rectangular coaxial line with a 50?characteristic impedance (see Figure 1). The device under test is exposed to a uniform TEM field. The TEM cell is a laboratory measurement system which can be used to generate test fields within 2 dB of the theoretical value if the device under test does not occupy an excessive portion of the test volume (see 5.3). Key 1Outer conductor (shield)5Coaxial connectors 2Septum (inner conductor)6Dielectric support (relative permittivity ?ru 1,4) 3Access door7Device under test 4Connector panel (optional)8Input/output leads Figure 1 TEM cell -,-,- ISO 11452-3:2001(E) © ISO 2001 All rights reserved3 5.2Instrumentation Figure 2 shows an example of a TEM cell test set-up. The TEM cell has high resonances in the region greater than the recommended upper frequency limit. A low pass filter with an attenuation of at least 60 dB at frequencies above 1,5 times the cut-off frequency of the TEM cell shall be installed (e.g. 200 MHz TEM cell: 60 dB for frequencies above 300 MHz). Key 1Signal generator 2Broadband amplifier 3Low pass filter 4Dual-directional coupler (30 dB decoupling ratio minimum) 5RF-power meter 6Peripheral 7Device under test 8Dielectric support 9Low pass filters/connector panel 10Coupler 11High power load (50 ?) 12Controller 13TEM cell a Preflected(reflected power). b Pforward(forward power). c Poutput(output power). Figure 2 Example TEM cell configuration -,-,- ISO 11452-3:2001(E) 4© ISO 2001 All rights reserved 5.3Test set-up 5.3.1General In order to maintain the homogeneous field in the TEM cell and obtain reproducible measurement results, the device under test shall be no larger than one-sixth of the cell (inside) height,b(see Figure 3 and Figure A.1). The device under test should be placed in the centre of the cell on a dielectric equipment support. The device under test and the wiring harness may be positioned in either of two arrangements, depending on whether the exposure of the device under test and the wiring harness (5.3.2) or that of the device alone (5.3.3) is being tested. 5.3.2Exposure of device under test and wiring harness (for major field coupling to the harness) The height of the dielectric support is one sixth of cell height b (see Figure 3). In order to obtain reproducible measurement results, the device under test together with its wiring harness or printed circuit board shall be placed in the same position in the TEM cell for each measurement. In addition to the direct RF-field coupling to the device under test, the use of an unshielded harness or printed circuit board will result in a common mode electrical field coupling and a differential mode magnetic field coupling, depending on the inclination and the width of the harness or circuit board. Key 1Device under test 2Dielectric support (relative permittivity ?ru 1,4) 3Printed circuit board (no ground plane) or wiring harness, unshielded 4Connector 5Coaxial connectors 6Connector panel 7TEM cell wall 8Cables 9Septum bTEM cell height (see annex A) Figure 3 Example test set-up Major field coupling to wiring harness (side view) -,-,- ISO 11452-3:2001(E) © ISO 2001 All rights reserved5 The connector panel should be attached to the TEM cell as close as possible to the printed lead system. The supply and signal leads from the connector in the cell wall are directly connected to the device under test using either a printed circuit board of length suitable for positioning the device under test in the allowed working region of the TEM cell, or a set of leads secured to a rigid support (see Figure 3 and Figure 4). The printed circuit board or supported wiring harness between the connector and the device under test will yield reproducible measurement results if the position of the leads and the device under test in the TEM cell are fixed. Key 1Device under test 2Dielectric support (relative permittivity ?ru 1,4) 3Printed circuit board or wiring harness 4Connector 5Coaxial connectors 6Connector panel 7TEM cell wall 8Cables NOTERF filters can be connected to the coaxial connectors in the connector panel or directly to the connector in the TEM cell wall. Figure 4 Example test set-up Major field coupling to wiring harness (top view) 5.3.3Exposure of device under test alone (for major field coupling to that device) The height of the dielectric support is 50 mm (see Figure 5). In order to obtain reproducible measurement results, the device under test shall be placed in the same position in the TEM cell for each measurement. -,-,- ISO 11452-3:2001(E) 6© ISO 2001 All rights reserved Dimensions in millimetres Key 1Device under test 2Dielectric support (relative permittivity?ru 1,4) 3Shielded wiring harness 4Connector 5Coaxial connectors 6Connector panel 7TEM cell wall 8Cables 9Septum bTEM cell height (see annex A) Figure 5 Example test set-up Major field coupling to device under test (side view) The connector panel should be attached to the TEM cell. The arrangement and nature of supply and signal leads shall be chosen in order to minimize the coupling on these leads, which shall be secured on the floor of the TEM cell and shielded between the connector in the cell wall and the device under test. This can be done by using metal tape with conductive adhesive to cover the leads on the floor of the TEM cell. The shield shall be in electrical contact with the cell floor, but shall not be in contact with the case of the device under test. 6Test procedure 6.1Test plan Prior to performing the test, a test plan shall be generated which shall cover the following: ?test set-up; ?frequency range; ?modulation; ?test set-up to be used (5.3.2 or 5.3.3); ISO 11452-3:2001(E) © ISO 2001 All rights reserved7 ?device under test mode of operation; ?device under test acceptance criteria; ?definition of test severity levels; ?test signal quality; ?use of net or output power measurements; ?device under test monitoring conditions; ?device under test orientation; ?test report content (see 6.3); ?any special instructions and changes from the standard test. Each device under test shall be tested under the most significant situations: i.e. at least in stand-by mode and in a mode where all the actuators can be excited. 6.2Test method CAUTION Hazardous voltages and fields may exist within the test area. Take care to ensure that the requirements for limiting the exposure of humans to RF energy are met. Make a net, or output, power (see Figure 2) measurement and calculate the electric field using equation 1: ZP E d ? ?(1) where ?E?is the absolute value of the electric field in volts per metre; Zis the characteristic impedance of the TEM cell in ohms (typically 50?); Pis net power (P = Pforward?Preflected) or output power, Poutput, in watts; dis the distance, in metres, between the floor and the TEM cell septum (b/2 in Figure A.1). An electrically small field-measuring device may be used to verify the calculated calibration curve for the field in the uniform field region. The conductor on the printed circuit board shall be designed to ha