Juniper EX9214 Hardware Manual page 194

installation torque to the nuts when they are improperly threaded can damage the
terminal stud.
CAUTION: The maximum torque rating for the terminal studs on the DC power
supply is 36 lb-in. (4.0 Nm) Excessive torque can damage the terminal studs. Use
only a torque-controlled driver or socket wrench to tighten the nuts on the DC
power supply terminals.)
10. Route the power cables along the cable restraint toward the left or right corner of the chassis. If
needed, thread plastic cable ties, which you must provide, through the openings on the cable
restraint to hold the power cables in place.
11. Replace the clear plastic cover over the terminal studs on the faceplate.
12. Verify that the power cabling is correct, that the cables are not touching or blocking access to
switch components, and that they do not drape where people could trip on them.
13. Switch on the dedicated customer site circuit breakers. Follow your site's procedures for safety and
to prevent ESD damage (see
NOTE: The DC power supplies in slots PEM0 and PEM1 must be powered by dedicated
power feeds derived from feed A and the DC power supplies in slots PEM2 and PEM3 must
be powered by dedicated power feeds derived from feed B. This configuration provides the
commonly deployed A/B feed redundancy for the system. For information about connecting
to DC power sources, see
54.
14. Verify that the INP0 OK or INP1 OK LED on the power supply are lit green steadily. If you are using
two feeds, verify that both INP0 OK and INP1 OK LEDs on the power supply are lit steadily in
green. The INP0 OK and INP1 OK LEDs are lit in amber color if the voltage at the input is in reverse
polarity. Check the polarity of the power cables to fix the condition.
15. On each of the DC power supplies, switch the DC circuit breaker to the center position before
moving it to the On (|) position.
NOTE: The circuit breaker might bounce back to the Off (O) position if you move the
breaker too quickly.
Prevention of Electrostatic Discharge Damage
"DC Power Supply Specifications for EX9214 Switches" on page
).
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