SMC Networks SMC7824M/ESW manual Connecting to a Power Source

CONNECTING TO A POWER SOURCE

To connect the switch to a power source:

1.First verify that the external DC power supply can provide -36 to

-72 VDC, 4 A minimum for the -48 VDC power conversion module.

2.Prepare two wires for each power source to be used (A or B). Use 10 to 24 AWG stranded copper wire. Make sure these wires are not plugged into the power source.

3.Use a wire stripper to carefully strip about a half an inch of the outer insulation off the end of each wire, exposing the copper core.

4.Twist the copper wire strands together to form a tight braid. If possible, solder the exposed braid of wire together for better conductivity.

5.Connect the external power feed and power ground/return lines to the DC plug (provided with the switch) as shown below. The power leads are labeled on the front of the chassis, above the DC power connection block. The -48 VDC power feed uses the “-48VDC” input and RETA/B (Return) lines for power source A and B respectively, while +24 VDC power feed uses the indicated “24VDC” input and GNDA/B (Ground) lines for power source A and B respectively*. Use a small flat-tip screwdriver to loosen the screws on the power plug and open the wire clamps.

6.Insert the wire leads into the openings shown in the figure below. Each lead inserted in the power plug must match the lead attached to the power source. Use the label above the DC power connection block to identify the appropriate power input and return or ground lines.

Warning: If the power leads are plugged into the wrong holes, the power supply will not work properly and may damage the switch.

*The 24 VDC power conversion module is not currently supported for this switch.

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