GarrettCom MAGNUM 6KM manual C2.0 Magnum 6KM, with DC Dual-Source option

Magnum 6KM Mobile Ethernet Switch Installation and User Guide 07/10

C2.0 MAGNUM 6KM, with DC Dual-Source option

The 6KM Switch models with the internal -48VDC, 12VDC, 24VDC, 110VDC, 125VDC and 250VDC Dual-Source power supply are designed for installations where a battery plant is the power source, and where two separate power sources are utilized in order to increase operational uptime and to simplify maintenance.

C3.0 DUAL-SOURCE OPTION, THEORY OF OPERATION

The Dual-Source DC power option is designed using diodes inside of the chassis on each DC power input line. A diode is placed in each of the four input lines (behind the four external power

connection terminals) so that power from an external source can only flow into the unit. This allows the unit to operate

whenever DC power is correctly

applied to either or both of the two inputs.

C4.0 FEATURES AND BENEFITS OF THE DUAL-SOURCE DESIGN

a)The Switch unit can receive power from either input, “A” or “B”. The hub will normally draw its power from the DC source with the highest voltage at a given time.

b)The Switch unit will not allow power to flow from a higher voltage input to a lower voltage input, i.e. the two DC power sources are not mixed together by the hub.

c)When one correct DC input is present, the Switch will receive power if the other DC input is absent, or even if it is connected with reverse polarity or shorted or grounded.

d)Reverse polarity connections, if they should accidentally occur on either input, will not damage the Switch or power supply internally (nor will it blow the fuse in the internal power supply) because of the blocking action of the diodes. This is true even if one input connection is reversed while the Switch is operating from the other source.

e)The Switch will not receive power (and will not work) when both inputs are simultaneously absent or are both incorrectly connected.

C5.0 6KM DUAL SOURCE INSTALLATION

This section describes the proper connection of the 12, 24, –48, 110, 125 and 250VDC dual source leads to the power input connector on the Magnum 6KM Switch.

The DC input connector on the Magnum 6KM Mobile Ethernet Switch is located on the left front of the unit. The power terminals are connected as shown below, and they are electrically floating inside the unit so that either may be grounded by the user if desired. The chassis is “earth” or ground (GND).

The mating power cable connection to the 6KM switch is made utilizing a RD24, locking, female connector. Simply align the keyed female connector to the 6KM male connector and twist the threaded lock to secure.

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