MIL-STD-461 Summary: EMI Characteristics of Military Equipment
Overview of MIL-STD-461G: the 19 test method codes (CE/CS/RE/RS), how requirements are applied, setup elements and typical emission/susceptibility test flow.
At a glanceHow to read a test codeTest methods (MIL-STD-461G)Emission tests: key pointsSusceptibility tests: key pointsPractical checkpointsOfficial sources
This page is a self-written reference summary. Limit values depend on the installation platform (aircraft, ship, ground, space and so on) and on the contract, so no numerical limits are shown. For actual testing follow the revision named in your contract (F, G, …) and its tailoring.
At a glance
- A U.S. Department of Defense interface standard that defines requirements and test methods for controlling the electromagnetic interference characteristics of subsystems and equipment.
- The widely used revision is G (2015); F (2007) was used before. Follow the revision stated in your contract.
- Requirements (limits and which tests apply) are set by platform applicability tables and may be tailored by the procuring authority.
- Unlike CISPR 32, there is no single limit per product class: which test applies at which limit is fixed by the contract.
How to read a test code
| Letter | Meaning |
|---|---|
| C / R | Conducted / Radiated |
| E / S | Emission / Susceptibility |
| Number | Test item number, e.g. CE102 = conducted emission test 102 |
Test methods (MIL-STD-461G)
| Code | Description | Frequency range |
|---|---|---|
| CE101 | Conducted emissions, audio-frequency currents, power leads | 30 Hz – 10 kHz |
| CE102 | Conducted emissions, RF potentials, power leads | 10 kHz – 10 MHz |
| CE106 | Conducted emissions, antenna port | 10 kHz – 40 GHz |
| CS101 | Conducted susceptibility, power leads | 30 Hz – 150 kHz |
| CS103 | Conducted susceptibility, antenna port, intermodulation | 15 kHz – 10 GHz |
| CS104 | Conducted susceptibility, antenna port, rejection of undesired signals | 30 Hz – 20 GHz |
| CS105 | Conducted susceptibility, antenna port, cross-modulation | 30 Hz – 20 GHz |
| CS109 | Conducted susceptibility, structure current | 60 Hz – 100 kHz |
| CS114 | Conducted susceptibility, bulk cable injection | 10 kHz – 200 MHz |
| CS115 | Conducted susceptibility, bulk cable injection, impulse excitation | Impulse test |
| CS116 | Conducted susceptibility, damped sinusoidal transients, cables and power leads | 10 kHz – 100 MHz |
| CS117 | Conducted susceptibility, lightning-induced transients, cables and power leads | Transient test |
| CS118 | Conducted susceptibility, personnel-borne electrostatic discharge | ESD test |
| RE101 | Radiated emissions, magnetic field | 30 Hz – 100 kHz |
| RE102 | Radiated emissions, electric field | 10 kHz – 18 GHz |
| RE103 | Radiated emissions, antenna spurious and harmonic outputs | 10 kHz – 40 GHz |
| RS101 | Radiated susceptibility, magnetic field | 30 Hz – 100 kHz |
| RS103 | Radiated susceptibility, electric field | 2 MHz – 40 GHz |
| RS105 | Radiated susceptibility, transient electromagnetic field | Transient test |
The table lists the test items of revision G. Item sets and numbering differ between revisions, so check the revision named in your contract.
Emission tests: key points
- CE102: a LISN (the MIL 5 µH configuration) is inserted in series with the power lead and voltage is measured from 10 kHz to 10 MHz. Its construction differs from the CISPR 50 µH/50 Ω LISN, so the two must not be mixed up.
- RE102: electric-field emissions from 10 kHz to 18 GHz measured with different antennas per band, such as a rod antenna (low frequency), biconical (mid band) and double-ridged horn (high frequency). Resolution bandwidths are specified per range (for example 100 kHz for 30 MHz–1 GHz and 1 MHz above 1 GHz).
- RE102 uses a peak detector throughout, unlike CISPR’s quasi-peak-centred approach.
- EUTs are normally set up over a ground plane, and since ambient noise must be well below the limit the tests are done in a shielded room or chamber.
Susceptibility tests: key points
- CS114 (bulk cable injection): an injection probe induces current on a cable bundle while a monitor probe verifies the actual current. The test current is set using power levels found during calibration.
- RS103: field levels are specified per platform, and the modulation differs from IEC 61000-4-3 (80 % AM): it uses pulse modulation and other prescribed schemes. The amplifier power needed varies strongly with distance, antenna gain and modulation.
- CS101: a low-frequency signal (30 Hz–150 kHz) is superimposed on the power line to evaluate ripple immunity.
- Pass/fail is judged against the equipment performance criteria defined in the test plan.
Practical checkpoints
- Before testing, fix the applicable tests, limits, revision and performance criteria in the test plan (EMITP) with your contract authority.
- Typical RE102 failures: switching-supply harmonics, poor cable-shield termination (pigtails), bad connector grounding. Bonding and conductive surface finish drive a large share of military EMI results.
- CS tests hinge on judging malfunction, so prepare monitoring (status signals, logs) in advance; it shortens test schedules.
Official sources
- The latest revision of U.S. DoD standards can be checked through ASSIST Quick Search (https://quicksearch.dla.mil).
- For domestic defence programmes, programme-specific test specifications and the competent authority’s requirements take precedence.
Related calculators
Standards summaries
Results and summaries are for reference. For certification and test reports use the latest official standard text and calibrated instrument data.