Connecting the JCS 1200 DC Platform to DC Power
The JCS 1200 DC power inputs are configured for DC isolated return (DC-I). The DC return terminal or conductor is not connected to the equipment frame or the grounding means of the equipment.
Caution: Only trained service personnel other than Juniper Networks service technicians are authorized to make the connections to and disconnections from the –48 volt DC power source. Juniper Networks service technicians are not certified or authorized to install or remove the –48 volt power cable. The customer is responsible for ensuring that only trained service personnel install or remove the –48 volt power cable.
The JCS 1200 DC platform has four DC power terminal connectors (see Figure 1). Each DC terminal has four M6 (0.25-inch) studs, one for –48 V DC, one for RETURN (RTN), and two for connecting the grounding cable (GND). Each terminal has a terminal cover. Remove the terminal cover before connecting cables to each terminal, and reinstall the terminal cover on each terminal before supplying power to the JCS 1200 platform. For more information, see Replacing a JCS 1200 DC Terminal Cover.
Figure 1: JCS 1200 DC Power Terminal Connectors
To connect the JCS 1200 DC platform to DC power:
- Ensure that the voltage across the DC power source cable leads is 0 V and that there is no chance that the cable leads might become active during installation.
- Verify that a licensed electrician has attached the cable lugs to the power cables.
- Switch both circuit breakers on the power supply faceplate to the off position (O).
- Attach an electrostatic discharge (ESD) grounding strap to your bare wrist and connect the strap to one of the ESD points on the chassis.
- Remove the terminal cover for each terminal.
- Attach the lugs on the DC source power cables to
the terminal studs, making sure the cables are not touching or in
the way of any JCS 1200 platform components. When connecting a cable
lug to each stud, install a flat washer on the stud, install the cable
lug, install a flat washer, install a split washer, and then install
a nut (see Figure 2).
Torque the wiring terminal nuts to 13.3 lb-in. (1.5 Nm).
Figure 2: Attaching the Cable Lugs to the JCS 1200 DC Power Terminal Connectors
- Attach the positive (+) DC source power cable lugs to the RTN (return) terminals.
- Attach the negative (–) DC source power cable lugs to the –48V (input) terminals.
- Attach the safety ground wire to the other two terminals.
- Verify that the power and ground cabling are correct.
- Replace the terminal cover for each terminal.
The Routing Engines in the JCS 1200 platform are connected to power but are not turned on. After the JCS 1200 platform has power, depending on the configuration settings, the Routing Engines might have to be individually turned on.