Magnum 4K8 Switches Installation and User Guide (10/04)
Series Fiber Switches Installation and User Guide, including Appendix B “Internal DC Power Supply Option”
C2.0 MAGNUM
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.
The functionality of the Magnum
C3.0 DUAL-SOURCE OPTION, THEORY OF OPERATION
The
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 INSTALLATION
This section describes the proper connection of the
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