Application of Military Electrical Connectors (2)

(5) Complete varieties and specifications
A. MIL-C-38999 variety specifications for modern military equipment can basically meet a variety of complex applications.

For example, in order to reduce weight, micro- and composite materials can be used, high-temperature and corrosion-resistant stainless steel shell materials can be used for rocket engine parts, and glass sintered sealed electrical connectors can be used for the connection parts inside and outside the submarine cabin.

Satellite and spacecraft can use electrical connectors that are resistant to thermal vacuum outgassing in the space environment. Except in very rare cases, the circular electrical connectors required can be found in the specification.

In MIL-C-38999, there is also a pull wire separation, that is, the electrical connector is detached. It contains almost any connection method, circular electrical connector suitable for various installation spaces and various vibration environments.

The main features and uses of the four series of MIL-C-38999

Series	Model	Connection	Main Features	Application
I	Same	Bayonet	long shell, anti-inclined, strong versatility	high-intensity vibration requires fast blind insertion and separation
II		Bayonet	short shell, no anti-inclined insertion, light weight and small size	requires small operating space, fast insertion and removal, and low vibration intensity
III		Threaded	long shell, anti-inclined insertion, three-head trapezoidal thread connection, only 360o rotation for insertion and separation, the plug has a self-locking mechanism, which can automatically prevent loosening	suitable for high temperature and long-term high-intensity vibration occasions, such as engine parts
IV	Individual spectrum	Push-pull	long shell, anti-inclined insertion, locking connection	high vibration occasions

B. Series I and Series II have six levels. They are E, G, H, P, T, and Y. These levels include non-airtight varieties, airtight varieties, potting varieties, and varieties specifically for aerospace. Series III and series IV have eleven levels, including non-airtight varieties, airtight varieties, fireproof varieties, and aerospace-specific varieties. From the level can provide non-airtight, airtight, fireproof, aerospace and other environmental options.

C. There are a variety of coatings for users to choose from, to meet different salt spray requirements and different temperature levels; Series I and II have 7 types of coatings, whose salt spray resistance is 24h, 48h, 500h, and high temperature resistance is 150 ℃, 175 ℃, and 200 ℃, series III, IV is divided into 11 levels, its salt fog resistance is 48 h, 500 h, 2000 h, high temperature resistance is 150 ℃, 175 ℃, and 200 ℃.

D. There are a variety of contacts such as common crimp contacts, temperature compensation contacts, winding contacts, two coaxial contacts, and three coaxial contacts.

E. The tail attachments include straight nuts, straight cable clamps, bent cable clamps, and shielded accessories.

F. Anti-interference
Has good anti-electromagnetic interference and shielding capabilities, can prevent electromagnetic interference (EMI), radio frequency interference (RFI), lightning strike (LEMP) and nuclear radiation (NEMP). MIL-C-38999 series III and IV have grounding springs, which directly connect the plug shell and the socket shell, which improves the electromagnetic interference shielding ability of the military style electrical connectors and meets the requirements of electromagnetic compatibility.