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1260-X121 User Manual
Racal Instruments
©
2005
Specifications 1-3
Shock
30g, 11ms, ½ sine wave
Vibration
0.013in. P-P, 5-55Hz
Bench Handling
4 in., 45
°
Temperature
Operating
0
°
C to +60
°
C
Non-operating -40
°
C to +70
°
C
Relative Humidity
85% Max., non-condensing at
<
30
°
C
Altitude
Operating
15,000
feet
Non-operating 15,000
feet
Power Requirements
+5VDC
300mA
Max.
+5VDC
40mA per energized relay.
Weight
15.71oz. (0.445kg)
MTBF (MIL-HDBK-217-FN2 method)
Including relays
783,549 hours at 25
°
C
718,344 hours at 30
°
C
Safety Standard EN61010-1
Pollution Degree 2
Power
Dissipation
While the cooling of the Adapt-a-Switch carrier is dependent upon
the chassis into which it is installed, the carrier can normally
dissipate approximately 160 W. The maximum power dissipation
for an individual module is 60W. Care must be taken, then, in the
selection and loading of the plug-in modules used in the carrier. It
is not possible to fully load the carrier, energize every relay, and
run full power through every set of contacts, all at the same time.
In practice this situation would never occur.
To properly evaluate the power dissipation of the plug-in modules,
examine the path resistance, the current passing through the relay
contacts, the ambient temperature, and the number of relays
closed at any one time.
For example, if a 1260-X121 module (containing 20 relays) has 5
relays closed, passing a current of 10 A, then:
Total power dissipation =
[(current)
2
* (path resistance) * 5 ] + (quiescent power)