Black Box MT160A Manual page 39

MicroCSU/DSU Cards and MicroRacks
1. Strip back the insulation on each of the wires about a quarter of an inch.
2. Use a small flatblade screwdriver to open the cage clamp as shown in Figure
3-2. Insert the stripped portion of the wire into the opening and remove the
screwdriver. The cage clamp will clamp the wire, producing a reliable
connection. Make sure all strands of wire are captured and that there is no
exposed wire.
3. Connect the earth ground wire to the frame ground terminal.
4. Connect the +VDC power wire to the +DC In terminal. Connect the -VDC
power wire to the -DC In terminal. The power-supply card is protected against
accidental reversal of polarity. If the DC-Input LED does not light, check the
polarity of the input wiring.
5. Connect the Alarm contacts as needed by your application.
Figure 23. Connecting bare wires to the rear power-entry card.
Replacing the Power Supply Fuse
The rack chassis power supply uses a 400 mA fuse for 120-VAC circuits, and a 200
mA fuse for 240-VAC circuits. The fuse compartment is located just below the AC
socket on the rear card. To replace the fuse, follow the steps on the next page:
1) Turn the power switch off and remove the power cord.
2) Using a small screwdriver, pop the compartment open (it will slide open
like a drawer). Depending upon the exact part used, the drawer may slide
completely out of the fuse holder or it may stop partway out.
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