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MIL-C-26500 Connectors
features
Amphenol®/Pyle® MIL-C-26500 Connectors are qualified to Mil-
itary Specification MIL-C-26500, as well as n umerous high per-
formance customer specifications. As the chart below
indicates, these connectors are available with aluminum or
stainless steel shells – bayonet or threaded – and are qualified
to meet the specifications of these MIL-C-26500 classes:
Crimp Contacts
Rear insertable, front releasable, crimp style contacts are
machined from a copper alloy material, plated gold over nickel,
and are qualified to specification MIL-C-39029. Contacts are
crimp ter m inated outside the connector assembly and inser ted
into the appropriate cavity by means of a hand tool.
Socket contacts utilize a multi-tined construction and feature a
“C” spring which grips the tines, and thus insures consistent
and repetitive insertion/withdrawal forces. Contact tines are
protected by a stainless steel shroud.
An optional pencil-clip thermocouple socket design is also
offered. See page 27 for more information on thermocouple
contacts.
Alternate Keying
All MIL-C-26500 Series Connectors with aluminum and stain-
less steel hardware , can be furnished with normal or any of fiv e
alternate key positions. (See page 4).
Each plug shell has a master key and four alternate keys. The
position of the alter nate keys in relation to the fixed master key
determines the key identification. Inserts are bonded to the
shell in relation to the master ke y, thus allowing positive protec-
tion against mismating when differing circuits e xist side b y side .
MIL-C-26500
Classes
Amphenol/
Pyle Series
Classes
Hardware
Description Finish
Class R:
(Environmental
Resistant) A Aluminum Alloy Anodize
Class G M Aluminum Alloy Chromium
Class E R Stainless Steel Passivated
Class K Firew all FPK/FYL Stainless Steel Passivated
Class H Hermetic HC CRS/Stainless
Steel Various
Connector Sealing
The insert design utilizes a combination of resilient and rigid
insulators to off er a connector with total sealing capabilities.
Bonded interfaces between the resilient and rigid dielectric
components eliminate air voids and thus protect the connector
from potential degradation due to moisture and altitude condi-
tions.
In Firewall Class K connectors the resilient inser t forms the pri-
mary contact seal and is bonded to a molded ceramic rigid
inser t. The insert assembly is physically bonded and mechani-
cally retained to the inside surface of the stainless steel shell,
providing a voidless, monoblock configuration impervious to
adverse environments.
A pressure seal at the connector interface is accomplished
through the aid of a coupling de vice which compresses the front
resilient insulations and thus offers a seal around each contact
which prevents the passage of air or moisture through the con-
tact cavity. Back resilient insulators are designed with a triple
sealing grip at each wire hole to offer positive sealing and pre-
vent wicking of moisture through the connector without the use
of exter nal clamping rings or adapters.
In addition, a dynamic “O” ring seal engages the front of the
plug shell when connectors are mated and offers yet another
barrier to moisture and containments.
Fluid/Temperature Resistance
The fluorosilicone compound elastomer, developed by Pyle-
National, exceeds all specification requirements and provides
excellent resistance to tear, compression set, fluids, and high
temperatures.
Amphenol/Pyle’s fluorosilicone compound offered in Class R,
G, E and K is capable of reliability resisting MIL-H-5606 hydrau-
lic fluid and MIL-L-9236 lubricating oil; as well as MIL-L-7808
and MIL-L-23699 lubricating oils, MIL-J-5624 (JP-5) jet fuel, gly-
col, and alkaline cleaning solutions of pH 10 or higher. Test
methods are as defined in MIL-C-26500 specification. Alter nate
compounds have been developed by Pyle-National to solve
unique user requirements not addressed by the specifications.
Connectors have the capability of resisting high ambient tem-
peratures up to 200°C (392°F) for long periods of time, thus
contributing to an extended connector life. Connectors will with-
stand a combined ambient and internal temperature due to
thermal rise of current carrying capacity of 238°C (469°F).
Amphenol®/Pyle® Firewall, Class K, connectors have the inher-
ent ability to resist high temperatures up to 460°F (total temper-
ature) for extended periods of time and can resist short time
exposures (20 minutes) to prevent passage of a direct 2000°F
flame.