Catalog 82181 Dimensions are in inches and Dimensions are shown for USA: 1-800-522-6752 South America: 55-11-2103-6000
Revised 5-06 millimeters unless otherwise reference purposes only. Canada: 1-905-470-4425 Hong Kong: 852-2735-1628
specified. Values in brackets Specifications subject Mexico: 52-55-1106-0800 Japan: 81-44-844-8013
www.tycoelectronics.com are metric equivalents. to change. C. America: 57-1-254-4444 UK: 44-208-420-8341
Soft Shell
Pin and Socket Connectors
104
(MR) Miniature Rectangular Connectors (Continued)
Performance
Characteristics
(Continued)
Maximum Current—Maximum cur-
rent rating of Miniature Rectangular con-
nectors is limited by the maximum oper-
ating temperature of the housings which
is 105°C including the temperature rise
of the contacts which is a maximum of
30°C. There are several variables which
have a direct effect on this maximum
current-carrying capability for a given
connector and must be considered for
each application. These variables are:
Wire Size—Larger diameter wire will
carry more current since it has less
internal resistance to current flow and
thus generates less heat. Longer wire
lengths also enhance current-carrying
capabilities since the wire conducts heat
away from the connector.
Connector Size—In general, the more
circuits in a connector, the less current
can be carried.
Ambient Temperature—The higher
the ambient temperature, the less current
can be carried in any given connector.
Printed Wiring Board Conductor
Size—The finished trace conductor
width and thickness should be maxi-
mized to allow for the greatest current-
carrying capacity and heat dissipation.
Miniature Rectangular connectors also
will withstand the following tests:
Vibration—10-55-10 cycles per
minute at .06 inch total excursion
Physical Shock—18 drops, 50 G saw-
tooth at 10 milliseconds
Housing Panel Retention—
50 lb. min.
Housing Lock Strength—20 lb. min.
Thermal Shock— -55°C to +85°C
Temperature-Humidity Cycling—
25°C to 65°C at 95 RH
Corrosion—48 hr. at 5% salt
concentration
Related Product Data
Product Specifications
108-1022 (MR) Miniature Rectangular
Connectors
108-1078 (MR) Miniature Rectangular
Headers
Current Rating Verification for 30°C Maximum Temperature Rise 100% Energized
Wire-to-Wire
MR Calculated Current Table
Number of Wire Gauge
Circuits 18 20 22 24 26
2 9.00 8.00 6.50 5.50 5.00
3 8.50 7.00 6.00 5.00 4.50
4 7.00 6.50 5.50 5.00 4.00
6 6.00 6.00 5.00 4.00 4.00
9 5.00 5.00 4.00 4.00 3.50
12 4.50 4.50 4.00 3.50 3.00
15 4.50 4.00 3.50 3.00 2.50
20 4.00 4.00 3.50 3.00 2.50
24 4.00 3.50 3.00 2.50 2.00
36 3.50 3.00 2.50 2.00 2.00
Values are based on initial Temperature Rise versus Current Testing and are intended to be a guide in the selection
of a connector family. All applications should be tested by the end user. The values listed are per circuit for fully loaded
housings being 100% energized. Note: All combinations were not tested and this chart contains interpolated and
extrapolated values.
Termination Resistance/Contact Crimp Tensile Force
Termination Contact
Resistance Crimp
Wire Size Test Resistance Tensile Force
AWG mm2Current Milliohms Force (Min.)
(Amps) (Max. Init.) lbs. N
26 .12 1 5.00 5 22
24 .2 1.5 5.00 8 36
22 .3 3 4.50 14 62
20 .5 4.5 4.00 14 62
18 .8 6 4.00 30 133
Note: This is the total resistance between wire crimps of a mated pin and socket.
Wire-to-Board
Due to the vast differences in trace geometry and printed circuit board configurations, we are unable to provide a sep-
arate current carrying chart for our printed circuit board header products. However, the above Wire-to-Wire charts may
be used as a guideline for headers if the trace width and thickness is equal to the listed wire gauge. For vertical head-
ers, only 95% of the Wire-to-Wire value should be used. For right-angle headers, only 75% of the Wire-to-Wire value
should be used. The charted values are only a tool for connector selection and will require the customer to fully test
their application.
Minimum Wire Lengths for T-Rise vs. Current Testing
AWG Min. Length (in.) AWG Min. Length (in.)
30 2.6 18 9.4
28 3.2 16 11.3
26 4.1 14 13.7
24 5.1 12 16.4
20 7.8 10 19.3
Note: If wire lengths used are less than those listed above, the current-
carrying ability of the system will be reduced due to less heat being
conducted away from the connector. The customer should fully test
all applications.