Military EMI Filters

Captor Corporation has extensive experience in manufacturing electromagnetic interference (EMI) filters for military and aerospace applications. We manufacture standard COTS-MIL EMI filters as well as custom EMI filters designed to meet a range of requirements, including RTCA/DO-160 and MIL-STD-461 regulations.


Captor Corporation offers several types of COTS MIL-STD-461 EMI filters. Each of these EMI filters are capable of withstanding harsh environments present in military applications. They provide maximum capacitance to ground limits for 50Hz to 400Hz in accordance with MIL-STD-461. The filters mitigate conducted emissions between 10kHz and 10MHz, making them suitable for use in the Navy. The primary difference between each COTS-MIL EMI filter is the type of power line it is designed for.

We manufacture the following COTS-MIL EMI Filters:

COTS MIL-STD-461 Single Phase EMI Filters

COTS MIL-STD-461 Single Phase EMI Filters

Designed for single phase power lines. This style can be used for DC applications as well.

COTS MIL STD 461 Three Phase Delta EMI Filter

COTS MIL-STD-461 Three-Phase Wye EMI Filters

Designed for three phase Wye power lines.

120/208VAC COTS MIL-STD-461 Three-Phase Delta EMI Filters

120/208VAC COTS MIL-STD-461 Three-Phase Delta EMI Filters

Designed for 120/208VAC Delta power lines.

254/440VAC COTS MIL-STD-461 Three-Phase Delta EMI Filters

254/440VAC COTS MIL-STD-461 Three-Phase Delta EMI Filters

Designed for 254/440VAC Delta power lines.

Our COTS-MIL EMI filters can be supplied with circuit breakers, Metal Oxide Varistors, and military connectors for I/O connections upon request.

MIL-COTS Filters CAD Catalog

Custom Military EMI Filters

At Captor Corporation, we design and manufacture EMI filters for military applications that meet a variety of specifications, including:

  • MIL-STD-461. System level emission testing and compliance determination.
  • MIL-STD-202. Component or system level testing for environmental conditions that the unit under test may experience in its operational life.
  • MIL-STD-220. A standard testing protocol that measures insertion loss of multiple and single circuit EMI filters and feed-through suppression capacitors at 10 GHz and below in 50 ohm systems.
  • MIL-PRF-15733. EMI filter requirement and testing specification.
  • RTCA/DO-160. A testing protocol published by the Radio Technical Commission for Aeronautics (RTCA) and used by major avionics and aerospace manufacturers for airborne equipment. The objective is to standardize component testing under environmental conditions that may be encountered during flight.

At Captor Corporation, our engineers can create EMI filters with the following specifications:

  • Insertion Loss: 0 to 100 dB
  • Voltage rating: 0 to 400 VDC, 0 to 480 VAC, with higher ratings available
  • Current: 0 to 400 amps, with higher ratings available
  • Frequency: DC frequencies up to 400 Hz, with other frequencies available
  • Operating temperatures: -55 °C to 85 °C
  • Storage Temperatures: -55 °C to 105 °C

Captor Corporation for Military Standard and Custom EMI Filters

At Captor Corporation, we manufacture a broad range of EMI filters that conform to various military standards and testing protocols, making them ideal for defense and aerospace applications. View our catalog of products and request information to learn more about the EMI filters we offer. If you have other questions about our products, contact us today.