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NEA® Dead Face Connector
Reliable in-flight electrical disconnects

Overview

EBAD’s Dead Face (DF) connectors are reliable in-flight electrical disconnects for satellite and spacecraft separation, missile staging, and umbilical separation. In addition to providing precision separation force, DF connectors provide electrical isolation prior to physical separation.

Principle of Operation

The EBAD NEA® DF electrical interconnects incorporate standard MIL-DTL-38999 inserts and MIL-C-39029 pin and socket contacts. DF connectors have an internal shuttle that disconnects and isolates electrical signals prior to physical separation at the separation plane, assuring upstream integrity of electrical interfaces, even during harsh environmental conditions after separation.

DF connectors are designed to work in conjunction with EBAD’s NEA® ZSF100P connectors at the separation interface. Each mated connector pair is factory calibrated to compensate for connector pin engagement and other retention forces, assuring precise and smooth separation. DF connectors feature a floating shell, eliminating jamming during mating and separation. Blind engagement of the plug and receptacle pairs is possible, since the connectors allow for linear and angular misalignment. Connectors can be mounted from the rear of the panel or bracket, allowing for ease of installation. The back side of the DF connector mates with a MIL-C-38999 Series III plug.

Applications

Typical applications include:

    • Satellite, spacecraft and payloads
    • Stage separation
    • Umbilical disconnects
    • Panel disconnect assemblies
    • Harsh environments

Key Features

    • Absolute electrical isolation prior to separation at the separation plane
    • Zero, positive, or negative separation force
    • Mounts from rear of panel or bracket
    • Tolerates wide range of linear and angular misalignment permitting blind engagement
    • MIL-DTL-38999 insert configurations
    • Full range of keying configurations
    • Service Class H
    • Utilizes MIL-C-39029 pin and socket contacts
    • Complete harness and disconnect assemblies available
    • DF200 and 201 series mates with our Model ZSF100 connectors

EBAD release device technology provides significant advantages.

Low Shock — There are three sources of shock with traditional pyrotechnic release devices; those include the pyrotechnic initiator and the resulting transfer of kinetic energy within the mechanism. The EBAD approach eliminates both of these sources of shock. There is no pyrotechnic initiator required so there is no initial shock and the restraint wire release mechanism is also not a significant contributor to shock.

A third source of shock is the energy stored in the release rod itself as well as any of the other components that are in the preload path. The nature of EBAD device’s gentle release of preload allows this stored energy to be dissipated over the release event minimizing the stored energy contribution to shock as well.

Fast Acting — With respect to shock, the action of EBAD devices is quite gentle yet the release event itself is still very fast. Since the fuse wire is extremely small the release event can be triggered in milliseconds. This capability allows multiple EBAD devices to be used in parallel where simultaneous release is required, such as large solar array panels and spacecraft stage separations.

Reliable —With simplicity comes reliability. The basic design of the NEA® HDRM is very simple with a minimum of moving components. The devices are robust and not sensitive to extreme environments or contaminants. High reliability is supported both analytically and by an extensive history of successful operation in mission critical applications.

Light Weight — EBAD devices offer extremely high preload release capacities versus unit mass. Some NEA® HDRM models have specific preload release capacities greater than 300N/g.

Temperature Insensitive — The simplicity of the EBAD release device mechanism is an asset not just for reliability but also with respect to temperature sensitivity. NEA® HDRMs are insensitive to extreme temperatures. Specific NEA® HDRMs have been qualified for operation at temperatures as low as 25K. The extreme low mass of the fuse wire results in actuation performance that insensitive to initial conditions.

Low Risk — NEA® HDRMs have an extensive history of use on a broad variety of spaceflight applications and are currently the baseline release device of choice on most major spacecraft buses. This history of reliability and mission success makes the NEA® HDRM our customers’ low risk option.

Compatible — NEA® HDRM devices have been designed to work with existing pyro firing circuits. The flexibility of the design however also allows operation with lower firing current if required.

Model DF Dead Face Connector Configurations
Connector Model Style Shell Size1 Insert Arrangement1 Mates With
DF200SS Receptacle 17 8 ZSF100P2
DF200SS, 201SS Receptacle 25 7, 29, 24, 61, 90 ZSF100P2

Notes:

1Existing shell sizes and insert arrangements shown. Other MIL-DTL-38999 shell size and insert arrangements available.
2See data sheet for NEA® Model ZSF100 connectors.

For more information:

Contact Us

*Commercial Item per FAR 2.101

Model DF Technical Specifications
Parameter Capability
Separation Force 0 N (0 lbf) (or adjustable to customer spec)
Engagement Force 90 N (20 lbf)
Linear Misalignment 0.76mm (0.03 in) min
Maximum Angular Misalignment 5 degree cone (half cone)
Qualification Temperature Range1 -55 degrees C  to +200 degrees C at 10-4 Torr
Short Duration Firewall 1,343 degrees C
Shock2 14,200 G peak
Random Vibration2 17 Grms, 180 sec per axis
Insulation Resistance 100 MΩ min at 1500 VDC
Dielectric Withstanding Voltage 2mA MAX leakage at 1,000 VAC
Shell to Shell Conductivity 10mV drop at 1 A
Mass3 380 g (0.84 lb)

Notes:

1The values presented for qualification temperature range are not a measure of the limits to the device.
2Shock and random vibration testing performed in the mated and unmated configurations.
3Represetative of DF200SS, 25-24 insert arrangement with electrical contacts. Contact EBAD for other configurations.