Outstanding Issues With The Mx480 Router - Juniper MX480 Hardware Manual

Calculating Power Requirements for MX480 Routers | 199

Outstanding Issues with the MX480 Router

This topic lists outstanding hardware issues with the MX480 router. For information about software issues,
see the Junos OS Release Notes.
In Junos OS Release 10.0R2, if a third AC supply is inserted in an empty slot (even though the power
supply is turned off and the AC cord is not plugged in), the operational power supplies' output voltage
reading in the Junos OS can show an inaccurate number (60-61V instead of 57V) under some conditions,
such as when the load is nearly 100% and the operating temperature exceeds 40C.
There is an input mode switch on each MX480 DC high capacity power supply, covered by a small plate.
The input mode switch tells the system what capacity feed is connected (60A or 70A), which in turn is
used for power inventory management When the input mode switch is set to '0' (zero): expect 60A
feeds, with a voltage range of -39V to -72VDC. When the input mode switch is set to '1' (one), expect
70A feeds or 60A feed with minimum voltage range 42V and up. The default setting is 1
In Junos OS Releases 10.0R3, 10.1R2, and 10.2R1, the MX480 DC high capacity power supply input
mode switch is not operating as expected, though this has no effect on the power supply operations, it
will generate alarms incorrectly. [PR532230]
NOTE:
All supplies should have the same feed setting.
Correct usage of the feed setting is required for all supplies in order to get the desired
power inventory management.
Juniper Networks strongly recommends that you install Junos OS Release 8.4R2 or later before deploying
the MX480 router into service.
The XFP cages and optics on the MX480 router are industry standard parts that have limited tactile
feedback for insertion of optics and fiber. You need to insert the optics and fiber firmly until the latch
is securely in place. [PR/98055]
Do not mix AC and DC power supplies on an MX480 router. Mixing of AC supplies and DC supplies may
damage your chassis. [PR/233340]
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