daa	PAHNESTOCK  TAPER	WIR
A.	Large Con
B.	High ~ont
C..,tong..Life

D. Small Siz

E. Mechanica

F. Easily Dis

G. Low Cost	

The “Standard” Wrap and the “Modified” Wrap A “Standard Wrap’ - is a wrapped connection that has only the prescribed number of turns of bare wire wrapped around the terminal. A ‘‘Modified Wrap’’ is a wrapped connection that has not only the prescribed number of bare wire turns; but also has a minimum of one-half turn of insulation wrapped around the terminal. A “Modified Wrap’~ made with solid wire will withstand more vibration then welded or soldered stranded wire of equal size (*).
(*)	Ref. to Bell Labs MM.54~<2332~S dated 3 November 1964.

Wire Wrapped Connections Widely Accepted.

To the best of our knowledge, the Underwriters’ Laboratories have not refused the use of wire wrapped connections on any manufacturer’s product submitted to Underwriters’ Laboratories for approval.

The wire wrapped connection has been approved by various branches of the government and military services. Mi! Standard 1130 has been issued to cover the wire wrapped connection for use by the military services. In addition, the
A wire wrapped connection is a permanent gas tight electrical connection. It consists of a helix of continuous solid uninsulated wire tightly wrapped around a suitahie terminal. ft is considered a ‘‘pressure connection” The wrapping hit wraps the wire around the terminal with
pressures which may go as high as 100,000 PSI. at the center of the contact area. This high pressure causes indentation of wire and terminal. Cold flow of the conductor causes this pressure to drop to approximately 30,000 PSI. where pressure stabilizes and remains constant.
Wire wrapped connections meet all the requirements of a good electrical connection. The following table shows a comparison of these requirements to some other common pressure connections:
Wire Wrapped Connections I The connection holds up extrer conditions of high temperature. high humidity. The wire wrapp extensive tests by Bell Telephc the connection would have a
these tests which include therm atmospheres and high humidity connection at intervals, it was appreciable increase in the arm connection. The high pressure terminal form a permanent gas any possibility of damage to th to corosive atmospheres.

U.S. Naval Avionics Facility al extensive testing and has cone! virtually indestructable. A cop~ be obtained by writing:
Administrator
Defense Document Center ft and Technical Informatior
Building No. 5, Cameron St
Alexandria, Virginia 22314
There is no need to be concern electrolysis between wire and material used for terminals ant conductor are very close togeth and, therefore, there is only a electrolysis which can take p/at take place is not at the contact~ is so high that the corrosive at

Reliability:	Wire Wrapped C Connections.
The failure rate of the wire wra to be one-tenth of that of the b projected failure rate for wire established for several of the ix hundred thousand connections. thousand connections for a sok company expressed the failure be .0008%/1000 hours operatk The wire wrapped connection rate of .000037%I1000 hours. I rate and with better than 100 b today, we have never had a rej wrapped connection. YOU CAP FAILURE RATE UNTIL YOU

Quality:	Easy to Check.
The quality of an individual co condition of the bit. wire and te

WIRE..
d the “Modified” Wrap :apped connection that has only ns of bare wire wrapped around Vrap’’ is a wrapped connection bed number of bare wire turns; me-half turn of insulation
[. A “Modified Wrap” made id more vibration then welded or nal size (*)
Z-8 dated 3 November 964.

is Widely Accepted.
the Underwriters’ Laboratories Ire wrapped connections on any aitted to Underwriters’

n has been approved by various and military services. Mi! we! to cover the wire wrapped litwy services. In addition, the ion (WS 6119) which is also ‘anies involved in military laris, Poseidon, Apollo, Sam IX ~emews and Hawk have been te wire wrapped connections into

jes Association) has issued ~e wire wrapping process. Copies
U.S. Naval Avionics Facility at Indianapolis (NAP!) has done extensive testing and has concluded that the connection is virtually indestructable A copy of this report (TR- 1242) may be obtained by writing:
Administrator
Defense Document Center for Scientific
and TechnicM Information CDDC
Building No. 5, Cameron Station
Alexandria, Virginia 22314
There is no need to be concerned about corrosion due to electrolysis between wire and terminal- In general, the material used for terminals and the material used for the conductor are very close together in the electromotive series; and, therefore, there is only a very slight amount of electrolysis which can take place. Any electrolysis which does take place is not a; the contact areas since the pressure there is so high that the corrosive atmosphere cannot penetrate.

Reliability: Wire Wrapped Connections vs. Soldered Connections.
The failure rate of the wire wrapped connection is considered to be one-tenth of that of the best solder connection. The projected failure rate for wire wrapped connections established for several of the military projects is one in a hundred thousand connections. This compares with one in ten thousand connections for a solder connection. Mother company expressed the failure rate of a solder connection to be .0008%/bOO hours operation.
The wire wrapped connection is considered to have a failure rate of 000037%/bOO hours. In spite of this predicted failure rate and with better than 100 billion connections in the field today, we have never had a reported failure of a solderless wrapped connection. YOU CAN’T DEVELOP AN ACTUAL FAILURE RATE UNTIL YOU GET A FAILURE!

Quality:	Easy to Check.
The quality of an individual connection is a function of the condition of the bit, wire and terminal being used. A periodic check of the stripping forces on a sample number of connections made by each wrapping bit used in production will satisfy the Quality Control Department as to the capabilities of an individual bit to continue to make good connections. In addition to the strip force test, a number of sample connections are given the unwrap test to ensure that the radius of the wrapping bit is not producing too great a tension of the wire.
WIRE	MIW NUMBER OF
GAUGE	ONDUCTOR TURNS
18 Ga.	
20 & 22 G	
24 & 260	
28 & 30 0	
32 Ga.	
14FV Automatic Machine Wire Sizes.
We can wrap 26 ga., and 30 ga. wire using the 14 FV Gardner Denver Automatic Wire Wrap Machines- The following table shows the proper wire size, terminal size and terminal grid combinations for automatic wrapping:
WIRE SIZE	TERMINAL SIZE	TERMINAL GRIP..	
26 Ga.	.045
x	.050
	x	.062
	x	.050		
OGa.	~O25
.020	l5OSq
125 Sq
.100	Sq.
.150	Stag.
.100	Stag.	
We also have the capability of wrapping all other applications such as .156 terminal spacings or applications where a unique wire size and terminal grid is used or where multi-wire sizes within a panel configuration are required with our semi-automatic wrapping equipment.
Twisted pair or twisted triplets can not be wrapped with the automatic machine but can be with our semi-automatic stations. Stranded wire also can be wrapped using semi-automatic or manual tools but it must be sokiered after wrapping.

Although it is not possible to make a solderless wrapped connection using a round terminal, it is practical in some cases to use a tool for connecting wires or resistors to round or pin type tenninals, then solder the connection for pennanency. This is referred to as a wrap-solder connection.