D38999/20FG35PB | 79-Pin Series III Square Flange Receptacle (Key B)
The D38999/20FG35PB is a size 21 MIL-DTL-38999 Series III receptacle with 79 pin contacts. Features “B” polarization and “F” electroless nickel finish for high-density grids.
999999 in stock
Share:
Product Categories
Request a Quote
D38999/20FG35PB Series III Triple-Start Thread and Mechanical Integrity
The D38999/20FG35PB is engineered for specialized electronic grids that must maintain absolute signal continuity under extreme mechanical stress. As a Series III component, it utilizes a self-locking, triple-start threaded coupling mechanism that provides superior security compared to traditional bayonet systems. This design ensures the connector remains firmly mated during high-frequency harmonic vibrations typical of aerospace propulsion environments. The Type 20 square flange housing allows for a stable four-point mounting on equipment panels, distributing the weight of heavy 79-wire cable harnesses evenly across the chassis to prevent mechanical fatigue.
Key Specifications
Shell Material | Voltage Rating | Current Rating | Operating Temp | Ingress Protection | Mating Cycles | Keying & Polarization | Coupling |
|---|---|---|---|---|---|---|---|
Aluminum alloy | ~1000 VAC | ~23 A | -65 °C to +200 °C | IP67 | 500 | B | threaded coupling |
High-Density 21-35 Layout and Pin Contact Precision
Within the size 21 aluminum alloy shell, the D38999/20FG35PB facilitates seventy-nine independent signal channels using the 21-35 insert arrangement. These channels utilize Size 22D pin contacts, which are precision-machined and finished with premium gold plating to ensure low contact resistance and maximum protection against atmospheric oxidation. This ultra-high-density configuration is essential for modern avionics stacks and tactical communication hubs where a massive volume of sensor data and control logic must be routed through a single, compact interface without compromising signal fidelity.
Specialized B-Keying for Enhanced System Safety
The “B” designation indicates a specialized polarization keyway, serving as a critical mechanical safeguard in dense electronic environments. In systems where multiple size 21 connectors are co-located on the same bulkhead, the “B” keying prevents accidental cross-mating with plugs configured for standard “N” or other alternative key positions. This physical lockout ensures that critical power or data streams are not misrouted, which could otherwise lead to catastrophic hardware failure. This standardized indexing logic simplifies complex assembly processes and streamlines field maintenance by providing intuitive, error-proof mating.
Environmental Hardening and Class F EMI Shielding
The “F” class finish of the D38999/20FG35PB involves electroless nickel plating over a high-strength aluminum shell, providing an optimal balance of corrosion resistance and electrical conductivity. This finish is vital for maintaining an effective Faraday cage around the 79-pole interface, ensuring superior EMI and RFI shielding performance in electromagnetically noisy environments. Internally, the connector is equipped with high-resilience fluorosilicone interfacial seals and rear wire-sealing grommets. These elements create a moisture-proof and dust-proof barrier capable of withstanding rapid pressure changes at high altitudes and exposure to maritime salt spray.
100% Scoop-Proof Protection and Field Serviceability
Reliability in the field is further enhanced by the D38999/20FG35PB’s 100% scoop-proof shell design. This feature ensures that the seventy-nine pin contacts are recessed deeply enough to prevent them from being bent or damaged if the mating plug is accidentally tilted during blind-mating scenarios. For ease of service, the receptacle utilizes a rear-release crimp contact system, allowing technicians to install or replace individual wires using standard tools without disassembling the entire panel mount. This combination of mechanical protection and serviceability makes the D38999/20FG35PB a future-proof interconnect solution for demanding global applications.
FAQ
How many contacts are in the 21-35 layout?
How many contacts are in the 21-35 layout?
The 21-35 arrangement provides 79 signal channels using size 22D pin contacts, offering one of the highest densities available in a size 21 shell.
What is the benefit of the "B" keyway polarization?
What is the benefit of the "B" keyway polarization?
It provides a unique mechanical alignment that prevents the connector from mating with standard “N” key plugs, which is vital for safety in multi-connector panels.
Does the "F" finish help with grounding?
Does the "F" finish help with grounding?
Yes, the electroless nickel (F) finish is highly conductive, ensuring a reliable low-impedance ground path to the chassis for effective EMI shielding.
Is the D38999/20FG35PB intermateable with Series I or II?
Is the D38999/20FG35PB intermateable with Series I or II?
No, MIL-DTL-38999 Series III connectors use a unique threaded coupling system that is not compatible with the bayonet-style Series I or Series II.
Can this connector be used in unpressurized aerospace compartments?
Can this connector be used in unpressurized aerospace compartments?
Absolutely. The integrated fluorosilicone seals and rugged construction are specifically designed to maintain integrity during rapid pressure cycles and high-altitude exposure.
Certification
- 测试文件后期要删除换成你自己的
