Juniper MX2020 Hardware Manual page 713

If output power is not load-balancing correctly in the same zone on an MX2000 router with a
high-capacity AC or DC power supply module, connect two feeds and change the DIP switch to 1 to
boost the voltage on the power supply module.
Each High Capacity AC or DC power supply accepts two AC or DC feeds in two unique AC or DC
receptacles. It is possible to operate with one feed, but there is a reduction in the power supply output.
The DIP switch must be set according to the number of AC or DC feeds that are present for the power
supply. Refer to Figure 296 on page 700
Figure 296: Setting the MX2000 Router DIP Switch
PWR OK FAULT
INP0 INP1
Position – 0 indicates that only one AC or DC feed is provided.
Position – 1 indicates that two AC or DC feeds are provided.
To check the DIP switch position:
1. Issue the show chassis power command and check to see how many feeds are connected. The following
example shows there are two AC input feeds connected for PEM 0 and one AC input feed connected
for PEM 1. This indicates that the DIP switch for PEM 0 is in position 1 and the DIP switch for PEM 1
is in position 0. These are the proper settings.
# run show chassis power
PEM 0:
State: Online
AC input: OK (2 feed expected, 2 feed connected)
Capacity: 4100 W (maximum 4100 W)
DC output: 855 W (zone 0, 15 A at 57 V, 20% of capacity)
PEM 1:
ON
0 1
700