Magnum 6K8-Series Industrial Field Switch Installation and User Guide 03/06)
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Power Supply (Internal, 125VDC Dual-Source, model # Dual-Src-125V)
DC Power Connector: First Source: “A+”, “A
-“
, 2nd Source “B
-
“, “B+”
GND: Terminal for “earth” or ground wire connection to the hub chassis
Input: Two separate sources, each at 88 - 300 VDC
With the exception of the dual DC input power connections and the power
supply, all specifications and configuration options for the Magnum 6K8-Series -48VDC,
24VDC and 125VDC models with this Dual-Source option are identical to those listed in
the
Magnum 6K8-Series Fiber Switches Installation and User Guide
, including Appendix
B “Internal DC Power Supply Option”
C2.0
MAGNUM 6K8-SERIES, with -48VDC, 24VDC and 125VDC Dual-Source
option (OPTIONAL)
The
6K8-Series-Switch
models with the internal -48VDC, 24VDC and
125VDC 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.
The functionality of the Magnum 6K8-Series Switch -48VDC, 24VDC and
125VDC Dual-Source Option units is identical to the standard AC-powered models.
Refer to the main sections of this
Installation and User Guide
for a detailed description
of the Magnum 6K8-Series Switches.
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)
GND
FUSE
+
-
SUPPLY
A+
A-
B-
B+
GND
CHASSIS
HUB
