MIL-STD-461E.pdf

MIL-STD-461E

20 AUGUST 1999

SUPERSEDING

MIL-STD-461D

11 JANUARY 1993

MIL-STD-462D

11 JANUARY 1993

DEPARTMENT OF DEFENSE

INTERFACE STANDARD

REQUIREMENTS FOR THE CONTROL OF

ELECTROMAGNETIC INTERFERENCE

CHARACTERISTICS OF SUBSYSTEMS AND

EQUIPMENT

AMSC F7352 AREA EMCS

DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited.

METRIC

ii

FOREWORD

1. This military standard is approved for use by all Departments and Agencies of the Department of Defense.

2. Beneficial comments (recommendations, additions, deletions) and any pertinent data which may be of use in improving this document should be addressed to: ASC/ENSI, 2530 Loop Road West, Wright-Patterson Air Force Base, OH 45433-7101, by using the self-addressed Standardization Document Improvement Proposal (DD Form 1426) appearing at the end of this document or by letter.

3. The test requirements previously contained in MIL-STD-462 used to verify compliance with MIL-STD-461 have been included in this version of MIL-STD-461.

4. The stated interface requirements are considered necessary to provide reasonable confidence that a particular subsystem or equipment complying with these requirements will function within their designated design tolerances when operating in their intended electromagnetic environment (EME). The procuring activity should consider tailoring the individual requirements to be more or less severe based on the design features of the intended platform and its mission in concert with personnel knowledgeable about electromagnetic compatibility issues affecting platform integration.

5. An appendix is included which provides the rationale and background for each requirement and verification section.

6. A committee consisting of representatives of the Army, Air Force, Navy, other DoD agencies, and Industry prepared this document.

CONTENTS

PARAGRAPH PAGE

iii

1. SCOPE

1.1 Purpose

1.2 Application

1.2.1 General applicability

1.2.2 Tailoring of requirements

1.3 Structure

1.4 Emission and susceptibility designations

2. APPLICABLE DOCUMENTS

2.1 Government documents

2.1.1 Government documents, drawings, and publications

2.2 Non-Government publications

2.3 Order of precedence

3. DEFINITIONS

3.1 General

3.2 Acronyms used in this standard

3.3 Above deck

3.4 Below deck

3.5 External installation

3.6 Flight-line equipment

3.7 Internal installation

3.8 Metric units

3.9 Non-developmental item

3.10 Safety critical

3.11 Test setup boundary

4. GENERAL REQUIREMENTS

4.1 General

4.2 Interface Requirements

4.2.1 Joint procurement

4.2.2 Filtering (Navy only)

4.2.3 Self-compatibility

4.2.4 Non-Developmental Items (NDI)

4.2.4.1 Commercial items

4.2.4.1.1 Selected by contractor

4.2.4.1.2 Specified by procuring activity

4.2.4.2 Procurement of equipment or subsystems having met other EMI requirements

4.2.5 Government Furnished Equipment (GFE)

4.2.6 Switching transients

4.3 Verification requirements

4.3.1 Measurement tolerances

PARAGRAPH PAGE

iv

4.3.2 Shielded enclosures

4.3.2.1 Radio Frequency (RF) absorber material

4.3.3 Other test sites

4.3.4 Ambient electromagnetic level

4.3.5 Ground plane

4.3.5.1 Metallic ground plane

4.3.5.2 Composite ground plane

4.3.6 Power source impedance

4.3.7 General test precautions

4.3.7.1 Accessory equipment

4.3.7.2 Excess personnel and equipment

4.3.7.3 Overload precautions

4.3.7.4 RF hazards

4.3.7.5 Shock hazard

4.3.7.6 Federal Communications Commission (FCC) restrictions

4.3.8 EUT test configurations

4.3.8.1 EUT design status

4.3.8.2 Bonding of EUT

4.3.8.3 Shock and vibration isolators

4.3.8.4 Safety grounds

4.3.8.5 Orientation of EUTs

4.3.8.6 Construction and arrangement of EUT cables

4.3.8.6.1 Interconnecting leads and cables

4.3.8.6.2 Input power leads

4.3.8.7 Electrical and mechanical interfaces

4.3.9 Operation of EUT

4.3.9.1 Operating frequencies for tunable RF equipment

4.3.9.2 Operating frequencies for spread spectrum equipment

4.3.9.3 Susceptibility monitoring

4.3.10 Use of measurement equipment

4.3.10.1 Detector

4.3.10.2 Computer-controlled receivers

4.3.10.3 Emission testing

4.3.10.3.1 Bandwidths

4.3.10.3.2 Emission identification

4.3.10.3.3 Frequency scanning

4.3.10.3.4 Emission data presentation

4.3.10.4 Susceptibility testing

4.3.10.4.1 Frequency scanning

4.3.10.4.2 Modulation of susceptibility signals

4.3.10.4.3 Thresholds of susceptibility

4.3.11 Calibration of measuring equipment

PARAGRAPH PAGE

v

4.3.11.1 Measurement system test

4.3.11.2 Antenna factors

5. DETAILED REQUIREMENTS

5.1 General

5.1.1 Units of frequency domain measurements

5.2 EMI control requirements versus intended installations

5.3 Emission and susceptibility requirements, limits, and test procedures

5.4 CE101, conducted emissions, power leads, 30 Hz to 10 kHz

5.4.1 CE101 applicability

5.4.2 CE101 limits

5.4.3 CE101 test procedure

5.4.3.1 Purpose

5.4.3.2 Test equipment

5.4.3.3 Setup

5.4.3.4 Procedures

5.4.3.5 Data presentation

5.5 CE102, conducted emissions, power leads, 10 kHz to 10 MHz

5.5.1 CE102 applicability

5.5.2 CE102 limits

5.5.3 CE102 test procedure

5.5.3.1 Purpose

5.5.3.2 Test equipment

5.5.3.3 Setup

5.5.3.4 Procedures

5.5.3.5 Data presentation

5.6 CE106, conducted emissions, antenna terminal, 10 kHz to 40 GHz

5.6.1 CE106 applicability

5.6.2 CE106 limits

5.6.3 CE106 test procedure

5.6.3.1 Purpose

5.6.3.2 Test equipment

5.6.3.3 Setup

5.6.3.4 Procedures

5.6.3.4.1 Transmit mode for transmitters and amplifiers

5.6.3.4.2 Receivers and stand-by mode for transmitters and amplifiers

5.6.3.5 Data presentation

5.6.3.5.1 Transmit mode for transmitters and amplifiers

5.6.3.5.2 Receivers and stand-by mode for transmitters and amplifiers

5.7 CS101, conducted susceptibility, power leads, 30 Hz to 150 kHz

5.7.1 CS101 applicability

5.7.2 CS101 limit

5.7.3 CS101 test procedure

PARAGRAPH PAGE

vi

5.7.3.1 Purpose

5.7.3.2 Test equipment

5.7.3.3 Setup

5.7.3.4 Procedures

5.7.3.5. Data presentation

5.8 CS103, conducted susceptibility, antenna port, intermodulation, 15 kHz to 10 GHz

5.8.1 CS103 applicability

5.8.2 CS103 limit

5.8.3. CS103 test procedures

5.8.3.1 Purpose

5.8.3.2 Test requirements

5.9 CS104, conducted susceptibility, antenna port, rejection of undesired signals, 30 Hz to 20 GHz

5.9.1 CS104 applicability

5.9.2 CS104 limit

5.9.3 CS104 test procedures

5.9.3.1 Purpose

5.9.3.2 Test requirements

5.10 CS105, conducted susceptibility, antenna port, cross modulation, 30 Hz to 20 GHz

5.10.1 CS105 applicability

5.10.2 CS105 limit

5.10.3 CS105 test procedures

5.10.3.1 Purpose

5.10.3.2 Test requirements

5.11 CS109, conducted susceptibility, structure current, 60 Hz to 100 kHz

5.11.1 CS109 applicability

5.11.2 CS109 limit

5.11.3 CS109 test procedures

5.11.3.1 Purpose

5.11.3.2 Test equipment

5.11.3.3 Setup

5.11.3.4 Procedures

5.11.3.5 Data Presentation

5.12 CS114, conducted susceptibility, bulk cable injection, 10 kHz to 200 MHz

5.12.1 CS114 applicability

5.12.2 CS114 limit

5.12.3 CS114 test procedures

5.12.3.1 Purpose

5.12.3.2 Test equipment

5.12.3.3 Setup

PARAGRAPH PAGE

vii

5.12.3.4 Procedures

5.12.3.5 Data presentation

5.13 CS115, Conducted susceptibility, bulk cable injection, impulse excitation

5.13.1 CS115 applicability

5.13.2 CS115 limit

5.13.3 CS115 test procedures

5.13.3.1 Purpose

5.13.3.2 Test equipment

5.13.3.3 Setup

5.13.3.4 Procedures

5.13.3.5. Data presentation

5.14 CS116, conducted susceptibility, damped sinusoidal transients, cables and power leads, 10 kHz to 100 MHz

5.14.1 CS116 applicability

5.14.2 CS116 limit

5.14.3 CS116 test procedures

5.14.3.1 Purpose

5.14.3.2 Test equipment

5.14.3.3. Setup

5.14.3.4 Procedures

5.14.3.5. Data presentation

5.15 RE101, Radiated emissions, magnetic field, 30 Hz to 100 kHz

5.15.1 RE101 applicability

5.15.2 RE101 limit

5.15.3 RE101 test procedures

5.15.3.1 Purpose

5.15.3.2 Test Equipment

5.15.3.3 Setup

5.15.3.4. Procedures

5.15.3.5 Data Presentation

5.16 RE102, radiated emissions, electric field, 10 kHz to 18 GHz

5.16.1 RE102 applicability

5.16.2 RE102 limits

5.16.3 RE102 test procedures

5.16.3.1 Purpose

5.16.3.2 Test Equipment

5.16.3.3 Setup

5.16.3.4 Procedures

5.16.3.5 Data Presentation

5.17 RE103, radiated emissions, antenna spurious and harmonic outputs, 10 kHz to 40 GHz

5.17.1 RE103 applicability

PARAGRAPH PAGE

viii

5.17.2 RE103 limits

5.17.3 RE103 test procedures

5.17.3.1 Purpose

5.17.3.2 Test Equipment

5.17.3.3 Setup

5.17.3.4. Procedures

5.17.3.5 Data Presentation

5.18 RS101, radiated susceptibility, magnetic field, 30 Hz to 100 kHz

5.18.1 RS101 applicability

5.18.2 RS101 limit

5.18.3 RS101 test procedures

5.18.3.1 Purpose

5.18.3.2 Test Equipment

5.18.3.3 Setup

5.18.3.4 Procedures

5.18.3.5 Data Presentation

5.18.4 RS101 alternative test procedures – AC Helmholtz coil

5.18.4.1 Purpose

5.18.4.2 Test Equipment

5.18.4.3 Setup

5.18.4.4 Procedures

5.18.4.5 Data Presentation

5.19 RS103, radiated susceptibility, electric field, 2 MHz to 40 GHz

5.19.1 RS103 applicability

5.19.2 RS103 limit

5.19.3 RS103 test procedures

5.19.3.1 Purpose

5.19.3.2 Test Equipment

5.19.3.3 Setup

5.19.3.4. Procedures

5.19.3.5 Data Presentation

5.19.4 RS103 alternative test procedures – reverberation chamber (mode-tuned)

5.19.4.1 Purpose

5.19.4.2 Test equipment

5.19.4.3. Setup

5.19.4.4 Procedure

5.19.4.5 Data Presentation

5.20 RS105, radiated susceptibility, transient electromagnetic field

5.20.1 RS105 applicability

5.20.2 RS105 limit

5.20.3 RS105 test procedures

PARAGRAPH PAGE

ix

5.20.3.1 Purpose

5.20.3.2 Test Equipment

5.20.3.3 Setup

5.20.3.4. Procedures

5.20.3.5. Data Presentation

6. NOTES

6.1 Intended use

6.2 Issue of DoDISS

6.3 Associated Data Item Descriptions

6.4 Tailoring guidance

6.5 Subject term (key word) listing

6.5 International standardization agreements

6.6 Changes from previous issue

6.7 Technical points of contact

FIGURE

FIGURE 1. RF absorber loading diagram FIGURE 2. General test setup FIGURE 3. Test setup for non-conductive surface mounted EUT FIGURE 4. Test setup for free standing EUT in shielded enclosure FIGURE 5. Test setup for free standing EUT FIGURE 6. LISN schematic FIGURE 7. LISN impedance FIGURE CE101-1. CE101 limit for submarine applications, DC FIGURE CE101-2. CE101 limit for submarine applications, 60 Hz FIGURE CE101-3. CE101 limit for submarine applications, 400 Hz FIGURE CE101-4. CE101 limit for Navy ASW aircraft and Army aircraft (including flight line) applications FIGURE CE101-5. Measurement system check FIGURE CE101-6. Measurement setup FIGURE CE102-1. CE102 limit (EUT power leads, AC and DC) for all applications FIGURE CE102-2. Measurement system check setup FIGURE CE102-3. Measurement setup FIGURE CE106-1. Setup for low power transmitters and amplifiers FIGURE CE106-2. Setup for high power transmitters and amplifiers FIGURE CE106-3. Setup for receivers and stand-by mode for transmitters and amplifiers FIGURE CS101-1. CS101 voltage limit for all applications FIGURE CS101-2. CS101 power limit for all applications FIGURE CS101-3. Calibration FIGURE CS101-4. Signal injection, DC or single phase AC

FIGURE PAGE

x

FIGURE CS101-5. Signal injection, 3-phase ungrounded FIGURE CS101-6. Signal injection, 3-phase wye FIGURE CS109-1. CS109 limit for all applications FIGURE CS109-2. Test Configuration FIGURE CS114-1. CS114 calibration limit for all applications FIGURE CS114-2. Maximum insertion loss for injection probes FIGURE CS114-3. Calibration setup FIGURE CS114-4. Bulk cable injection evaluation FIGURE CS115-1. CS115 signal characteristics for all applications FIGURE CS115-2. Calibration setup FIGURE CS115-3. Bulk cable injection FIGURE CS116-1. Typical CS116 damped sinusoidal waveform FIGURE CS116-2. CS116 limit for all applications FIGURE CS116-3. Typical test setup for calibration of test waveform FIGURE CS116-4. Typical set up for bulk cable injection of damped sinusoidal transients FIGURE RE101-1. RE101 limit for all Army applications FIGURE RE101-2. RE101 limit for all Navy applications FIGURE RE101-3. Calibration configuration FIGURE RE101-4. Basic test setup FIGURE RE102-1. RE102 limit for surface ship applications FIGURE RE102-2. RE102 limit for submarine applications FIGURE RE102-3. RE102 limit for aircraft and space system applications FIGURE RE102-4. RE102 limit for ground applications FIGURE RE102-5. Basic test setup FIGURE RE102-6. Antenna positioning FIGURE RE102-7. Multiple antenna positions FIGURE RE103-1. Calibration and test setup for radiated harmonics and spurious emissions, 10 kHz to 1 GHz FIGURE RE103-2. Calibration and test setup for radiated harmonics and spurious emissions, 1 GHz to 40 GHz FIGURE RS101-1. RS101 limit for all Navy applications FIGURE RS101-2. RS101 limit for all Army applications FIGURE RS101-3. Calibration of the radiating system FIGURE RS101-4. Basic test setup FIGURE RS101-5. Calibration of Helmholtz coils FIGURE RS101-6. Test setup for Helmholtz coils FIGURE RS103-1. Test equipment configuration FIGURE RS103-2. Multiple test antenna locations for frequency > 200 MHz FIGURE RS103-3. Multiple test antenna locations for N positions, D > 3 meters FIGURE RS103-4. Receive antenna procedure (1 to 40 GHz) FIGURE RS103-5. Reveberation chamber setup

FIGURE PAGE

xi

FIGURE RS103-6. Reverberation Chamber Overview FIGURE RS105-1. RS105 limit for all applications FIGURE RS105-2. Typical calibration setup using parallel plate radiation system FIGURE RS105-3. Typical test setup using parallel plate radiation system

TABLE

TABLE I. Absorption at normal incidence TABLE II. Bandwidth and measurement time TABLE III. Susceptibility scanning TABLE IV. Emission and susceptibility requirements TABLE V. Requirement matrix TABLE VI. CS114 limit curves TABLE VII. RS103 limits TABLE VIII. Required number of tuner positions for a reverberation chamber

APPENDIX

APPENDIX A: MIL-STD-461E Application Guide A-1

1. SCOPE

1.1 Purpose.

This standard establishes interface and associated verification requirements for the control of the electromagnetic interference (emission and susceptibility) characteristics of electronic, electrical, and electromechanical equipment and subsystems designed or procured for use by activities and agencies of the Department of Defense. Such equipment and subsystems may be used independently or as an integral part of other subsystems or systems. This standard is best suited for items that have the following features: electronic enclosures that are no larger than an equipment rack, electrical interconnections that are discrete wiring harnesses between enclosures, and electrical power input derived from prime power sources. This standard should not be directly applied to items such as modules located inside electronic enclosures or entire platforms.

The principles in this standard may be useful as a basis for developing suitable requirements for those applications. Data item requirements are also included.

1.2 Application.

1.2.1 General applicability.

The applicability of the emission and susceptibility requirements is dependent upon the types of equipment or subsystems and their intended installations as specified herein.

1.2.2 Tailoring of requirements.

Application-specific environmental criteria may be derived from operational and engineering analyses on equipment or subsystems being procured for use in specific systems or platforms.

When analyses reveal that the requirements in this standard are not appropriate for that procurement, the requirements may be tailored and incorporated into the request-for-proposal, specification, contract, order, and so forth. The test procedures contained in this document shall be adapted by the testing activity for each application. The adapted test procedures shall be documented in the Electromagnetic Interference Test Procedures (EMITP)(See 6.3).

1.3 Structure.

The standard has two primary sections, the main body and the appendix. The main body contains the interface and verification requirements of this standard. The appendix is non-contractual and provides rationale for the requirements and guidance on their interpretation and use. The paragraph numbering scheme for the appendix parallels the numbering for the main body requirements except that an extra “0” digit is included (for example, 20.0 rather than 2.0).

Occasionally, there are references in the main body to appendix material where an obvious need exists for the appendix information to be examined.

1.4 Emission and susceptibility designations.

The emissions and susceptibility and associated test procedure requirements in this standard are designated in accordance with an alphanumeric coding system. Each requirement is identified by a two letter combination followed by a three digit number. The number is for reference purposes only. The meaning of the individual letters is as follows:

C = Conducted R = Radiated E = Emission

S = Susceptibility

a. Conducted emissions requirements are designated by "CE---."

b. Radiated emissions requirements are designated by "RE---."

c. Conducted susceptibility requirements are designated by "CS---."

d. Radiated susceptibility requirements are designated by "RS---."

e. "---" = numerical order of requirement from 101 to 199.

2. APPLICABLE DOCUMENTS

2.1 Government documents.

2.1.1 Government documents, drawings, and publications.

The following other Government documents, drawings, and publications form a part of this document to the extent specified herein. Unless otherwise specified, the issues are those cited in the solicitation.

DEPARTMENT OF DEFENSE (DoD)

DoDI 6055.11 - Protection of DoD Personnel from Exposure to Radio Frequency Radiation and Military Exempt Lasers

SD-2 - Buying Commercial and Nondevelopmental Items

NORTH ATLANTIC TREATY ORGANIZATION

STANAG 3516 - Electromagnetic Interference and Test Methods for Aircraft Electrical and Electronic Equipment

STANAG 4435 - Electromagnetic Compatibility Testing Procedures and Requirements for Naval Electrical and Electronic Equipment (Surface Ship, Metallic Hull)

STANAG 4436 - Electromagnetic Compatibility Testing Procedures and Requirements for Naval Electrical and Electronic Equipment (Surface Ship, Non-Metallic Hull)

STANAG 4437 - Electromagnetic Compatibility Testing Procedures and Requirements for Naval Electrical and Electronic Equipment (Submarines)

(Copies of the DoDI 6055.11, SD-2, and STANAGs are available from the Department of Defense Single Source Stock Point, 700 Robbins Avenue, Building 4D, Philadelphia PA 19111- 5094 [Telephone 215-697-2179].)

2.2 Non-Government publications.

The following documents form a part of this document to the extent specified herein. Unless otherwise specified, the issues of the documents which are DoD adopted are those listed in the issue of the DoDISS cited in the solicitation. Unless otherwise specified, the issues of documents not listed in the DoDISS are the issues of the documents cited in the solicitation (see 6.2).

AMERICAN NATIONAL STANDARDS INSTITUTE (ANSI)

ANSI/IEEE C63.2 - Standard for Instrumentation-Electromagnetic Noise and Field Strength, 10 kHz to 40 GHz, Specifications

ANSI/IEEE C63.4 - Standard for Electromagnetic Compatibility, Radio-Noise Emissions from Low Voltage Electrical and Electronic Equipment in the Range of 9 kHz to 40 GHz, Methods of Measurement

ANSI/IEEE C63.14 - Standard Dictionary for Technologies of Electromagnetic Compatibility (EMC), Electromagnetic Pulse (EMP), and Electrostatic Discharge (ESD)

ANSI/NCSL Z540-1 - General Requirements for Calibration Laboratories and Measuring and Test Equipment

(DoD activities may obtain copies of ANSI documents from the Standardization Document Order Desk, 700 Robbins Avenue, Building 4D, Philadelphia PA 19111-5094. Other Government agencies and the private sector may address application for copies of ANSI documents to the American National Standards Institute, 11 West 42nd Street, New York, New York 10036 [Telephone: 212-642-4900 or Fax: 212-398-0023]; or the Institute of Electrical and Electronics Engineers, Incorporated (IEEE), 445 Hoes Lane, Piscataway NJ 08855-1331 [Telephone: 800-701-4333 or Fax: 908-981-9667].)

AMERICAN SOCIETY FOR TESTING AND MATERIALS (ASTM)

ASTM E 380 - Standard for Metric Practice (DoD adopted)

(Application for copies should be addressed to the American Society for Testing and Materials, 1916 Race Street, Philadelphia PA 19103-1187 [Telephone: 215-299-5585 or FAX:

215-977-9679].)

INTERNATIONAL STANDARDS ORGANIZATION

ISO 10012-1 - Quality Assurance Requirements for Measuring Equipment

(Application for copies of ISO documents should be addressed to ISO, International Organization for Standardization, 3 rue de Varembe, 1211 Geneve 20, Geneve, Switzerland [Telephone: 41 22 734 0150].)

SOCIETY OF AUTOMOTIVE ENGINEERS (SAE)

ARP 958 - Electromagnetic Interference Measurement Antennas; Standard Calibration Requirements and Methods

(Application for copies should be addressed to the Society of Automotive Engineers, Incorporated, 400 Commonwealth Drive, Warrendale PA 15096 [Telephone: 412-776-4841 or

FAX: 412-776-5760].)

2.3 Order of precedence.

In the event of a conflict between the text of this standard and the references cited herein, the text of this standard shall take precedence. Nothing in this document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained.

3. DEFINITIONS

3.1 General.

The terms used in this standard are defined in ANSI C63.14. In addition, the following definitions are applicable for the purpose of this standard.

3.2 Acronyms used in this standard.

a. ASW - Anti-submarine Warfare

b. BIT - Built-in Test

c. EMC - Electromagnetic Compatibility

d. EME - Electromagnetic Environment

e. EMI - Electromagnetic Interference

f. EMICP - Electromagnetic Interference Control Procedures

g. EMITP - Electromagnetic Interference Test Procedures

h. EMITR - Electromagnetic Interference Test Report

i. ERP - Effective Radiated Power

j. EUT - Equipment Under Test

k. GFE - Government Furnished Equipment

l. ISM - Industrial, Scientific and Medical

m. LISN - Line Impedance Stabilization Network

n. NDI - Non-Developmental Item

o. RF - Radio Frequency

p. RMS - Root Mean Square

q. TEM - Transverse Electromagnetic

r. TPD - Terminal Protection Device

3.3 Above deck.

An area on ships which is not considered to be “below deck” as defined herein.

3.4 Below deck.

An area on ships which is surrounded by a metallic structure, or an area which provides significant attenuation to electromagnetic radiation, such as the metal hull or superstructure of a surface ship, the pressure hull of a submarine and the screened rooms in non-metallic ships.

3.5 External installation.

An equipment location on a platform which is exposed to the external electromagnetic environment, such as an aircraft cockpit which does not use electrically conductive treatments on the canopy or windscreen.

3.6 Flight-line equipment.

Any support equipment that is attached to or used next to an aircraft during pre-flight or post-flight operations, such as uploading or downloading data, maintenance diagnostics, or equipment functional testing.

3.7 Internal installation.

An equipment location on a platform which is totally inside an electrically conductive structure, such as a typical avionics bay in an aluminum skin aircraft.

3.8 Metric units.

Metric units are a system of basic measures which are defined by the International System of Units based on "Le System International d'Unites (SI)", of the International Bureau of Weights and Measures. These units are described in ASTM E 380.

3.9 Non-developmental item.

Non-developmental item is a broad, generic term that covers material available from a wide variety of sources both Industry and Government with little or no development effort required by the procuring activity.

3.10 Safety critical.

A category of subsystems and equipment whose degraded performance could result in loss of life or loss of vehicle or platform.

3.11 Test setup boundary.

The test setup boundary includes all enclosures of the Equipment Under Test (EUT) and the 2 meters of exposed interconnecting leads (except for leads which are shorter in the actual installation) and power leads required by 4.3.8.6.

4. GENERAL REQUIREMENTS

4.1 General.

Electronic, electrical, and electromechanical equipment and subsystems shall comply with the applicable general interface requirements in 4.2. General requirements for verification shall be in accordance with 4.3. These general requirements are in addition to the applicable detailed emission and susceptibility requirements and associated test procedures defined in 5.0.

4.2 Interface Requirements.

4.2.1 Joint procurement.

Equipment or subsystems procured by one DoD activity for multi-agency use shall comply with the requirements of the user agencies.

4.2.2 Filtering (Navy only).

The use of line-to-ground filters for EMI control shall be minimized. Such filters establish low impedance paths for structure (common-mode) currents through the ground plane and can be a major cause of interference in systems, platforms, or installations because the currents can couple into other equipment using the same ground plane. If such a filter must be employed, the line-to-ground capacitance for each line shall not exceed 0.1 microfarads (µF) for 60 Hertz (Hz) equipment or 0.02 µF for 400 Hz equipment. For submarine DC-powered equipment and aircraft DC-powered equipment, the filter capacitance from each line-to-ground at the user interface shall not exceed 0.075 µF/kW of connected load. For DC loads less than 0.5 kW, the filter capacitance shall not exceed 0.03 µF. The filtering employed shall be fully described in the equipment or subsystem technical manual and the Electromagnetic Interference Control Procedures (EMICP) (See 6.3).

4.2.3 Self-compatibility.

The operational performance of an equipment or subsystem shall not be degraded, nor shall it malfunction, when all of the units or devices in the equipment or subsystem are operating together at their designed levels of efficiency or their design capability.

4.2.4 Non-Developmental Items (NDI).

In accordance with the guidance provided by DoD SD-2, the requirements of this standard shall be met when applicable and warranted by the intended installation and platform requirements.

4.2.4.1 Commercial items.

4.2.4.1.1 Selected by contractor.

When it is demonstrated that a commercial item selected by the contractor is responsible for equipment or subsystems failing to meet the contractual EMI requirements, either the commercial item shall be modified or replaced or interference suppression measures shall be employed, so that the equipment or subsystems meet the contractual EMI requirements.

4.2.4.1.2 Specified by procuring activity.

When it is demonstrated by the contractor that a commercial item specified by the procuring activity for use in an equipment or subsystem is responsible for failure of the equipment or subsystem to meet its contractual EMI requirements, the data indicating such failure shall be included in the Electromagnetic Interference Test Report (EMITR) (See 6.3). No modification or replacement shall be made unless authorized by the procuring activity.

4.2.4.2 Procurement of equipment or subsystems having met other EMI requirements.

Procurement of equipment and subsystems electrically and mechanically identical to those previously procured by activities of DoD or other Federal agencies, or their contractors, shall meet the EMI requirements and associated limits, as applicable in the earlier procurement, unless otherwise specified by the Command or agency concerned.

4.2.5 Government Furnished Equipment (GFE).

When it is demonstrated by the contractor that a GFE is responsible for failure of an equipment or subsystem to meet its contractual EMI requirements, the data indicating such failure shall be included in the EMITR. No modification shall be made unless authorized by the procuring activity.

4.2.6 Switching transients.

Switching transient emissions that result at the moment of operation of manually actuated switching functions are exempt from the requirements of this standard. Other transient type conditions, such as automatic sequencing following initiation by a manual switching function, shall meet the emissions requirements of this standard.

4.3 Verification requirements.

The general requirements related to test procedures, test facilities, and equipment stated below, together with the detailed test procedures included in 5.0, shall be used to determine compliance with the applicable emission and susceptibility requirements of this standard. Any procuring activity approved exceptions or deviations from these general requirements shall be documented in the Electromagnetic Interference Test Procedures (EMITP) (See 6.3). Equipment that are intended to be operated as a subsystem shall be tested as such to the applicable emission and susceptibility requirements whenever practical. Formal testing is not to commence without approval of the EMITP by the Command or agency concerned. Data that is gathered as a result of performing tests in one electromagnetic discipline may be sufficient to satisfy requirements in another. Therefore, to avoid unnecessary duplication, a single test program should be established with tests for similar requirements conducted concurrently whenever possible.

4.3.1 Measurement tolerances.

Unless otherwise stated for a particular measurement, the tolerance shall be as follows:

a. Distance: ±5%

b. Frequency: ±2%

c. Amplitude, measurement receiver: ±2 dB

d. Amplitude, measurement system (includes measurement receivers, transducers, cables, and so forth): ±3 dB

e. Time (waveforms): ±5%

f. Resistors: ±5%

e. Capacitors: ±20%

4.3.2 Shielded enclosures.

To prevent interaction between the EUT and the outside environment, shielded enclosures will usually be required for testing. These enclosures prevent external environment signals from contaminating emission measurements and susceptibility test signals from interfering with electrical and electronic items in the vicinity of the test facility. Shielded enclosures must have adequate attenuation such that the ambient requirements of 4.3.4 are satisfied. The enclosures must be sufficiently large such that the EUT arrangement requirements of paragraph 4.3.8 and antenna positioning requirements described in the individual test procedures are satisfied.

4.3.2.1 Radio Frequency (RF) absorber material.

RF absorber material (carbon impregnated foam pyramids, ferrite tiles, and so forth) shall be used when performing electric field radiated emissions or radiated susceptibility testing inside a shielded enclosure to reduce reflections of electromagnetic energy and to improve accuracy and repeatability. The RF absorber shall be placed above, behind, and on both sides of the EUT, and behind the radiating or receiving antenna as shown in Figure 1. Minimum performance of the material shall be as specified in Table I. The manufacturer's certification of their RF absorber material (basic material only, not installed) is acceptable.

TABLE I. Absorption at normal incidence.

Frequency Minimum absorption

80 MHz - 250 MHz 6 dB above 250 MHz 10 dB

4.3.3 Other test sites.

If other test sites are used, the ambient requirements of paragraph 4.3.4 shall be met.

4.3.4 Ambient electromagnetic level.

During testing, the ambient electromagnetic level measured with the EUT de-energized and all auxiliary equipment turned on shall be at least 6 dB below the allowable specified limits when the tests are performed in a shielded enclosure. Ambient conducted levels on power leads shall be measured with the leads disconnected from the EUT and connected to a resistive load which draws the same rated current as the EUT. When tests are performed in a shielded enclosure and the EUT is in compliance with required limits, the ambient profile need not be recorded in the EMITR. When measurements are made outside a shielded enclosure, the tests shall be performed during times and conditions when the ambient is at its lowest level. The ambient shall be recorded in the EMITR and shall not compromise the test results.

4.3.5 Ground plane.

The EUT shall be installed on a ground plane that simulates the actual installation. If the actual installation is unknown or multiple installations are expected, then a metallic ground plane shall be used. Unless otherwise specified below, ground planes shall be 2.25 square meters or larger in area with the smaller side no less than 76 centimeters. When a ground plane is not present in the EUT installation, the EUT shall be placed on a non-conductive table.

4.3.5.1 Metallic ground plane.

When the EUT is installed on a metallic ground plane, the ground plane shall have a surface resistance no greater than 0.1 milliohms per square. The DC resistance between metallic ground planes and the shielded enclosure shall be 2.5 milliohms or less. The metallic ground planes shown in Figures 2 through 5 shall be electrically bonded to the floor or wall of the basic shielded room structure at least once every 1 meter. The metallic bond straps shall be solid and maintain a five-to-one ratio or less in length to width. Metallic ground planes used outside a shielded enclosure shall extend at least 1.5 meters beyond the test setup boundary in each direction.

4.3.5.2 Composite ground plane.

When the EUT is installed on a conductive composite ground plane, the surface resistivity of the typical installation shall be used. Composite ground planes shall be electrically bonded to the enclosure with means suitable to the material.

4.3.6 Power source impedance.

The impedance of power sources providing input power to the EUT shall be controlled by Line Impedance Stabilization Networks (LISNs) for all measurement procedures of this document unless otherwise stated in a particular test procedure. LISNs shall not be used on output power leads. The LISNs shall be located at the power source end of the exposed length of power leads specified in paragraph 4.3.8.6.2. The LISN circuit shall be in accordance with the schematic shown in Figure 6. The LISN impedance characteristics shall be in accordance with Figure 7.

The LISN impedance shall be measured at least annually under the following conditions:

a. The impedance shall be measured between the power output lead on the load side of the LISN and the metal enclosure of the LISN.

b. The signal output port of the LISN shall be terminated in fifty ohms.

c. The power input terminal on the power source side of the LISN shall be unterminated.

The impedance measurement results shall be provided in the EMITR.

4.3.7 General test precautions.

4.3.7.1 Accessory equipment.

Accessory equipment used in conjunction with measurement receivers shall not degrade measurement integrity.

4.3.7.2 Excess personnel and equipment.

The test area shall be kept free of unnecessary personnel, equipment, cable racks, and desks.

Only the equipment essential to the test being performed shall be in the test area or enclosure.

Only personnel actively involved in the test shall be permitted in the enclosure.

4.3.7.3 Overload precautions.

Measurement receivers and transducers are subject to overload, especially receivers without preselectors and active transducers. Periodic checks shall be performed to assure that an overload condition does not exist. Instrumentation changes shall be implemented to correct any overload condition.

4.3.7.4 RF hazards.

Some tests in this standard will result in electromagnetic fields which are potentially dangerous to personnel. The permissible exposure levels in DoDI 6055.11 shall not be exceeded in areas where personnel are present. Safety procedures and devices shall be used to prevent accidental exposure of personnel to RF hazards.

4.3.7.5 Shock hazard.

Some of the tests require potentially hazardous voltages to be present. Extreme caution must be taken by all personnel to assure that all safety precautions are observed.

4.3.7.6 Federal Communications Commission (FCC) restrictions.

Some of the tests require high level signals to be generated that could interfere with normal FCC approved frequency assignments. All such testing should be conducted in a shielded enclosure.

Some open site testing may be feasible if prior FCC coordination is accomplished.

4.3.8 EUT test configurations.

The EUT shall be configured as shown in the general test setups of Figures 1 through 5 as applicable. These setups shall be maintained during all testing unless other direction is given for a particular test procedure.

4.3.8.1 EUT design status.

EUT hardware and software shall be representative of production. Software may be supplemented with additional code that provides diagnostic capability to assess performance.

4.3.8.2 Bonding of EUT.

Only the provisions included in the design of the EUT shall be used to bond units such as equipment case and mounting bases together, or to the ground plane. When bonding straps are required, they shall be identical to those specified in the installation drawings.

4.3.8.3 Shock and vibration isolators.

EUTs shall be secured to mounting bases having shock or vibration isolators if such mounting bases are used in the installation. The bonding straps furnished with the mounting base shall be connected to the ground plane. When mounting bases do not have bonding straps, bonding straps shall not be used in the test setup.

4.3.8.4 Safety grounds.

When external terminals, connector pins, or equipment grounding conductors are available for safety ground connections and are used in the actual installation, they shall be connected to the ground plane. Arrangement and length shall be in accordance with 4.3.8.6.1.

4.3.8.5 Orientation of EUTs.

EUTs shall be oriented such that surfaces which produce maximum radiated emissions and respond most readily to radiated signals face the measurement antennas. Bench mounted EUTs shall be located 10 ±2 centimeters from the front edge of the ground plane subject to allowances for providing adequate room for cable arrangement as specified below.

4.3.8.6 Construction and arrangement of EUT cables.

Electrical cable assemblies shall simulate actual installation and usage. Shielded cables or shielded leads (including power leads and wire grounds) within cables shall be used only if they have been specified in installation requirements. Cables shall be checked against installation requirements to verify proper construction techniques such as use of twisted pairs, shielding, and shield terminations. Details on the cable construction used for testing shall be included in the

EMITP.

4.3.8.6.1 Interconnecting leads and cables.

Individual leads shall be grouped into cables in the same manner as in the actual installation.

Total interconnecting cable lengths in the setup shall be the same as in the actual platform installation. If a cable is longer than 10 meters, at least 10 meters shall be included. When cable lengths are not specified for the installation, cables shall be sufficiently long to satisfy the conditions specified below. At least the first 2 meters (except for cables which are shorter in the actual installation) of each interconnecting cable associated with each enclosure of the EUT shall be run parallel to the front boundary of the setup. Remaining cable lengths shall be routed to the back of the setup and shall be placed in a zig-zagged arrangement. When the setup includes more than one cable, individual cables shall be separated by 2 centimeters measured from their outer circumference. For bench top setups using ground planes, the cable closest to the front boundary shall be placed 10 centimeters from the front edge of the ground plane. All cables shall be supported 5 centimeters above the ground plane.

4.3.8.6.2 Input power leads.

Two meters of input power leads (including neutrals and returns) shall be routed parallel to the front edge of the setup in the same manner as the interconnecting leads. Each input power lead, including neutrals and returns, shall be connected to a LISN (see 4.3.6). Power leads that are bundled as part of an interconnecting cable in the actual installation shall be configured in the same fashion for the 2 meter exposed length and then shall be separated from the bundle and routed to the LISNs. After the 2 meter exposed length, the power leads shall be terminated at the LISNs in as short a distance as possible. The total length of power lead from the EUT electrical connector to the LISNs shall not exceed 2.5 meters. All power leads shall be supported 5 centimeters above the ground plane. If the power leads are twisted in the actual installation, they shall be twisted up to the LISNs.

4.3.8.7 Electrical and mechanical interfaces.

All electrical input and output interfaces shall be terminated with either the actual equipment from the platform installation or loads which simulate the electrical properties (impedance, grounding, balance, and so forth) present in the actual installation. Signal inputs shall be applied to all applicable electrical interfaces to exercise EUT circuitry. EUTs with mechanical outputs shall be suitably loaded. When variable electrical or mechanical loading is present in the actual installation, testing shall be performed under expected worst case conditions. When active electrical loading (such as a test set) is used, precautions shall be taken to insure the active load meets the ambient requirements of 4.3.4 when connected to the setup, and that the active load does not respond to susceptibility signals. Antenna ports on the EUT shall be terminated with shielded, matched loads.

4.3.9 Operation of EUT.

During emission measurements, the EUT shall be placed in an operating mode which produces maximum emissions. During susceptibility testing, the EUT shall be placed in its most susceptible operating mode. For EUTs with several available modes (including software controlled operational modes), a sufficient number of modes shall be tested for emissions and susceptibility such that all circuitry is evaluated. The rationale for modes selected shall be included in the EMITP.

4.3.9.1 Operating frequencies for tunable RF equipment.

Measurements shall be performed with the EUT tuned to not less than three frequencies within each tuning band, tuning unit, or range of fixed channels, consisting of one mid-band frequency and a frequency within ±5 percent from each end of each band or range of channels.

4.3.9.2 Operating frequencies for spread spectrum equipment.

Operating frequency requirements for two major types of spread spectrum equipment shall be as follows:

a. Frequency hopping. Measurements shall be performed with the EUT utilizing a hop set which contains a minimum of 30% of the total possible frequencies. This hop set shall be divided equally into three segments at the low, mid, and high end of the EUT's operational frequency range.

b. Direct sequence. Measurements shall be performed with the EUT processing data at the highest possible data transfer rate.

4.3.9.3 Susceptibility monitoring.

The EUT shall be monitored during susceptibility testing for indications of degradation or malfunction. This monitoring is normally accomplished through the use of built-in-test (BIT), visual displays, aural outputs, and other measurements of signal outputs and interfaces.

Monitoring of EUT performance through installation of special circuitry in the EUT is permissible; however, these modifications shall not influence test results.

4.3.10 Use of measurement equipment.

Measurement equipment shall be as specified in the individual test procedures of this standard.

Any frequency selective measurement receiver may be used for performing the testing described in this standard provided that the receiver characteristics (that is, sensitivity, selection of bandwidths, detector functions, dynamic range, and frequency of operation) meet the constraints specified in this standard and are sufficient to demonstrate compliance with the applicable limits.

Typical instrumentation characteristics may be found in ANSI C63.2.

4.3.10.1 Detector.

A peak detector shall be used for all frequency domain emission and susceptibility measurements. This device detects the peak value of the modulation envelope in the receiver bandpass. Measurement receivers are calibrated in terms of an equivalent Root Mean Square (RMS) value of a sine wave that produces the same peak value. When other measurement devices such as oscilloscopes, non-selective voltmeters, or broadband field strength sensors are used for susceptibility testing, correction factors shall be applied for test signals to adjust the reading to equivalent RMS values under the peak of the modulation envelope.

4.3.10.2 Computer-controlled receivers.

A description of the operations being directed by software for computer-controlled receivers shall be included in the EMITP. Verification techniques used to demonstrate proper performance of the software shall also be included.

4.3.10.3 Emission testing.

4.3.10.3.1 Bandwidths.

The measurement receiver bandwidths listed in Table II shall be used for emission testing. These bandwidths are specified at the 6 dB down points for the overall selectivity curve of the receivers. Video filtering shall not be used to bandwidth limit the receiver response. If a controlled video bandwidth is available on the measurement receiver, it shall be set to its greatest value. Larger receiver bandwidths may be used; however, they may result in higher measured emission levels. NO BANDWIDTH CORRECTION FACTORS SHALL BE APPLIED TO

TEST DATA DUE TO THE USE OF LARGER BANDWIDTHS.

TABLE II. Bandwidth and measurement time.

Frequency Range 6 dB Bandwidth

Dwell Time Minimum Measurement Time Analog Measurement Receiver

30 Hz - 1 kHz 10 Hz 0.15 sec 0.015 sec/Hz

1 kHz - 10 kHz 100 Hz 0.015 sec 0.15 sec/kHz

10 kHz - 150 kHz 1 kHz 0.015 sec 0.015 sec/kHz

150 kHz - 30 MHz 10 kHz 0.015 sec 1.5 sec/MHz

30 MHz - 1 GHz 100 kHz 0.015 sec 0.15 sec/MHz

Above 1 GHz 1 MHz 0.015 sec 15 sec/GHz

4.3.10.3.2 Emission identification.

All emissions regardless of characteristics shall be measured with the measurement receiver bandwidths specified in Table II and compared against the applicable limits. Identification of emissions with regard to narrowband or broadband categorization is not applicable.

4.3.10.3.3 Frequency scanning.

For emission measurements, the entire frequency range for each applicable test shall be scanned.

Minimum measurement time for analog measurement receivers during emission testing shall be as specified in Table II. Synthesized measurement receivers shall step in one-half bandwidth increments or less, and the measurement dwell time shall be as specified in Table II. For equipment that operates such that potential emissions are produced at only infrequent intervals, times for frequency scanning shall be increased as necessary to capture any emissions.

4.3.10.3.4 Emission data presentation.

Amplitude versus frequency profiles of emission data shall be automatically generated and displayed at the time of test and shall be continuous. The displayed information shall account for all applicable correction factors (transducers, attenuators, cable loss, and the like) and shall include the applicable limit. Manually gathered data is not acceptable except for verification of the validity of the output. Plots of the displayed data shall provide a minimum frequency resolution of 1% or twice the measurement receiver bandwidth, whichever is less stringent, and minimum amplitude resolution of 1 dB. The above resolution requirements shall be maintained in the reported results of the EMITR.

4.3.10.4 Susceptibility testing.

4.3.10.4.1 Frequency scanning.

For susceptibility measurements, the entire frequency range for each applicable test shall be scanned. For swept frequency susceptibility testing, frequency scan rates and frequency step sizes of signal sources shall not exceed the values listed in Table III. The rates and step sizes are specified in terms of a multiplier of the tuned frequency (fo) of the signal source. Analog scans refer to signal sources which are continuously tuned. Stepped scans refer to signal sources which are sequentially tuned to discrete frequencies. Stepped scans shall dwell at each tuned frequency for the greater of 3 seconds or the EUT response time. Scan rates and step sizes shall be decreased when necessary to permit observation of a response.

TABLE III. Susceptibility scanning.

Frequency Range Analog Scans

Maximum Scan Rates Stepped Scans

Maximum Step Size

30 Hz - 1 MHz 0.0333fo/sec 0.05 fo

1 MHz - 30 MHz 0.00667 fo/sec 0.01 fo

30 MHz - 1 GHz 0.00333 fo/sec 0.005 fo

1 GHz - 8 GHz 0.000667 fo/sec 0.001 fo

8 GHz - 40 GHz 0.000333 fo/sec 0.0005 fo

4.3.10.4.2 Modulation of susceptibility signals.

Susceptibility test signals for CS114 and RS103 shall be pulse modulated (on/off ratio of 40 dB minimum) at a 1 kHz rate with a 50% duty cycle.

4.3.10.4.3 Thresholds of susceptibility.

When susceptibility indications are noted in EUT operation, a threshold level shall be determined where the susceptible condition is no longer present. Thresholds of susceptibility shall be determined as follows and described in the EMITR:

a. When a susceptibility condition is detected, reduce the interference signal until the EUT recovers.

b. Reduce the interference signal by an additional 6 dB.

c. Gradually increase the interference signal until the susceptibility condition reoccurs.

The resulting level is the threshold of susceptibility.

d. Record this level, frequency range of occurrence, frequency and level of greatest susceptibility, and other test parameters, as applicable.

4.3.11 Calibration of measuring equipment.

Test equipment and accessories required for measurement in accordance with this standard shall be calibrated in accordance with ANSI/NCSL Z540-1 or ISO 10012-1 or under an approved calibration program traceable to the National Institute for Standards and Technology. In particular, measurement antennas, current probes, field sensors, and other devices used in the measurement loop shall be calibrated at least every 2 years unless otherwise specified by the procuring activity, or when damage is apparent.

4.3.11.1 Measurement system test.

At the start of each emission test, the complete test system (including measurement receivers, cables, attenuators, couplers, and so forth) shall be verified by injecting a known signal, as stated in the individual test procedure, while monitoring system output for the proper indication.