Juniper QFX5220, Руководство по оборудованию, Страница: 137 / 247

The battery returns of the DC power supply must be connected as an isolated DC return (DC-I).
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Ensure that you have the following parts and tools available:
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A spare JPSU-1600W-DC-AFO for QFX5220-128C
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ESD grounding strap
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Slotted (–) screwdriver, 1/4-in., with a torque range between 6 lb-in (0.68 Nm) to 7 lb-in (0.79 Nm)
CAUTION: You must use an appropriate torque-controlled tool to tighten the screws
on the DC power cable connector. Do not overtighten the screws. Applying excessive
torque damages the terminal block and the wiring tray. The absolute maximum torque
that may be applied to this screw is 10 lb-in (1.13 Nm).
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Power cables to connect DC power to the QFX5220-128C. The DC power cables–a straight DC power
cable (CBL-JNP-PWR-DSUB). See Table 21 on page 73 .
CAUTION: Do not mix AC and DC power supplies in the same chassis.
NOTE: Each power supply must be connected to a dedicated power source outlet.
To connect DC power to a QFX5220-128C:
1. To prevent damage to the equipment caused by static discharge, attach an ESD grounding strap to
your bare wrist, and connect the strap to an approved site ESD grounding point.
2. Ensure that the power supplies are fully inserted in the chassis and that the latches are secure.
3. Connect the green grounding wire in each DC power cable (CBL-JNP-PWR-DSUB) to ground.
4. Connect each power supply to the power source by inserting the DC connector into the power supply.
See Figure 56 on page 141 .
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