Mx2000 Dc Power Supply Module (240 V China) Description - Juniper MX2020 Hardware Manual

MX2000 DC Power Supply Module (240 V China) Description

The MX2020 supports a two zone DC power system. Each zone (upper and lower) is provided power by
one half of the power subsystem. In the DC power configuration, the router contains up to eighteen DC
PSMs located at the rear of the chassis in slots PSM0 through PSM8 (bottom), and slots PSM9 through
PSM17 (top) (left to right). The DC PSMs in slots PSM0 through PSM8 provide power to the lower half
of the router components, MPCs in slot 0 through 9, CB-REs in slot 0 and 1, SFBs in slot 0 through 7, and
Fan Trays 0, 1, and 2. The DC PSMs in slots PSM9 through PSM17 provide power to the upper half of the
router components, MPCs in slot 10 through 19, CB_REs in slot 0, and 1, SFBs in slot 0 through 7, and
Fan Trays 0, 2, and 3.
NOTE: The MX2020 systems configured for DC (240 V China) input power must use only DC
(240 V China) PDMs and DC PSMs. AC and DC PSMs or PDMs must not be mixed within a single
system.
Up to nine PSMs may be connected in parallel to increase available system power across MPCs as needed
and provide redundancy.
Figure 52: DC Power Supply Module (240 V China)
The DC power system is feed redundant. Each DC PSM can be connected to two separate feeds from
different sources that are used to provide feed redundancy. If two feeds are connected, PSM input power
will be drawn from the feed with the higher voltage present. There are two PDMs per power subsystem
capable of carrying nine feeds each. Connect feeds from one source to one PDM and feeds from the other
source to the second PDM of the power subsystem. The primary input of the PSM is a dual redundant
feed, INP0 and INP1. Both feeds are active during operation, but both feeds may or may not be providing
Figure 50 on page 113) shows the DC PSM.
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