Juniper MX2010, Руководство по оборудованию

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Connecting an MX2010 DC Power Distribution Module Cable
WARNING: Before performing DC power procedures, disconnect all power sources.
To ensure that all power is off, locate the circuit breaker on the panel board that
services the DC circuit, switch the circuit breaker to the OFF position, and tape the
switch handle of the circuit breaker in the OFF position.
To connect a power cable for a DC PDM:
1. Locate a replacement power cable that meets the specifications defined in “MX2010 DC Power (-48
V) System Electrical Specifications” on page 201 .
2. Verify that a licensed electrician has attached a cable lug to the replacement power cable.
3. Verify that the –48V LED is off.
4. Secure the power cable lug to the terminal studs, first with the flat washer, then with the split washer,
and finally with the nut. Apply between 23 lb-in. (2.6 Nm) and 25 lb-in. (2.8 Nm) of torque to each nut
(see Figure 133 on page 311 ). Do not overtighten the nut. (Use a 7/16-in. [11 mm)] torque-controlled
driver or socket wrench.)
CAUTION: Ensure that each power cable lug seats flush against the surface of
the terminal block as you are tightening the nuts. Ensure that each nut is properly
threaded onto the terminal stud. The nut should be able to spin freely with your
fingers when it is first placed onto the terminal stud. Applying installation torque
to the nut when the nut is improperly threaded might result in damage to the
terminal stud.
CAUTION: The maximum torque rating of the terminal studs on the DC PDM
is 25 lb-in. (33.89 Nm). The terminal studs might be damaged if excessive torque
is applied. Use only a torque-controlled driver or socket wrench to tighten nuts
on the DC PDM terminal studs.
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