Juniper EX8208 Hardware Manual page 181

If you are using DC power supplies, ensure that the source power cables are connected to the appropriate
terminal: the positive (+) source cable to the return terminal (RTN) and the negative (-) source cable
to the input terminal (-48 VDC).
6. Switch on the site circuit breakers.
7. Flip a power supply's Enable switch to the on position (ON). See
power supply faceplate LEDs. If the power supply is installed correctly and functioning normally, the
INPUT OK / IN OK and OUTPUT OK / OUT OK LEDs light and remain constantly lit. The FAIL LED
does not light.
Figure 55: Flip the Enable Switch to the ON position
8. Repeat Step 7 for the remaining power supplies installed in the switch.
9. On the external management device, monitor the startup process to ensure that the system boots
properly.
NOTE: After you power on a power supply, wait for at least 60 seconds before you turn it off.
After you power off a power supply, wait for at least 60 seconds before you turn it back on.
If the system is completely powered off when you switch on a power supply, the SRE or RE
module boots as the power supply completes its startup sequence.
After you power on a power supply, it can take up to 60 seconds for status indicators such as
power supply LEDs and the show chassis operational mode CLI command display to indicate
that the power supply is functioning normally. Ignore any error indicators that might appear
during the first 60 seconds.
Figure 55 on page 181. Observe the
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