Page 14 - Circular Connector Backshells and Accessories

How to Order
Circular Connector Backshells
How
to Order

moplastic materials as an alternative to conductive
Backshell-to-Connector Coupling metal materials and finishes. Composite products
can eliminate corrosion problems completely in in-
Glenair offers four different coupling styles to meet every terconnect systems and should be considered for
application requirement:
all harsh application environments.
Direct Coupling The problems associated with corrosion are
compounded by the need to produce parts which
are electrically conductive. To prevent EMI from
permeating into system electronics, conductive
cable shielding is grounded to plated backshells
and connectors to take the unwelcome EMI to
earth. The challange is to produce conductive,
Direct couplers thread directly onto the connector by
rotating the entire part. A separate toothed follower pro- plated products which both prevent EMI and resist
vides backshell-to-connector grounding. corrosion in harsh application environments. At
Glenair this work takes place in three areas:
Rotatable Coupling
1. Strict attention to dissimilar metal combinations;
2. The specification of corrosion-resistant mate-
rials such as stainless steels and composites in se-
vere environments wherever possible; and
3. The use of surface coatings such as nickel,
zinc or gold plating to isolate base metals from re-
active electrolytes.
Rotatable designs utilize a free-spinning, toothed cou-
pling nut for easier installation. The selection of compatible (non-galvanic)
surface finishes is a critical step in backshell speci-
Self-Locking, Rotatable Coupling fication. To prevent dissimilar metal corrosion,
customers should note material and finish specifi-
cations for connectors and cable shields before
selecting connector accessory hardware. As a
general rule, the backshell material and finish
should match that of the chosen connector.
Electroless nickel plating (code M) provides a
Rotatable Self-Lockers add a ratcheted detent "clicker" low resistance conductive finish appropriate for
to prevent de-coupling due to extreme vibration and shock.
most H (magnetic) and E (electrical) field EMI ap-
Positive-Lock, Non-Detent Coupling plications, and is ideally suited for benign environ-
ments not exposed to salt-spray. For environmen-
tal applications, a sacrificial overplating, such as
cadmium plate over electroless nickel (code NF),
is recommended. Glenair zinc-nickel over electro-
less nickel (code ZN) may also be specified for en-
vironmental applications which require ASTMB 841-
91 approval but are prohibited from using cadmium.
Glenair Mod Code -445 ("NESTOR") coupling mecha-
nism corresponds to AS85049 style "N" non-detent, rotat- Non-EMI applications may utilize nonconductive fin-
able coupling with spring-loaded interface. ishes such as Black Anodize (Code C). See Table
II for other standard finish options.

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