Juniper ACX4000 Hardware Manual page 114

a. The cable with very low resistance (indicating a closed circuit) to chassis ground is the DC input
cable (-).
b. The cable with very large resistance (indicating an open circuit) to chassis ground is the return
cable (+).
4. Remove the screws and flat washers from the terminals.
5. Secure each power cable lug to the terminal with the flat washers and screw (see
106). Apply between 8 lb-in. (0.9 Nm) and 9 lb-in. (1.02 Nm) of torque to each screw. Do not
overtighten the screw. (Use a number 2 Phillips screwdriver.)
a. Secure the positive DC source power cable lug to the return (+) terminal.
b. Secure the negative DC source power cable lug to the input (–) terminal.
CAUTION: Ensure that each power cable lug seats flush against the surface of the
terminal block as you are tightening the screws. Ensure that each screw is properly
threaded into the terminal. Applying installation torque to the screw when improperly
threaded may result in damage to the terminal.
CAUTION: The maximum torque rating of the terminal screws on the DC power
supply is 9 lb-in. (1.02 Nm). The terminal screws may be damaged if excessive torque is
applied. Use only a torque-controlled driver to tighten screws on the DC power supply
terminals. Use an appropriately-sized driver, with a maximum torque capacity of 9 lb-
in. or less. Ensure that the driver is undamaged and properly calibrated and that you
have been trained in its use. You may wish to use a driver that is designed to prevent
overtorque when the preset torque level is achieved.
6. Replace the clear plastic cover over the terminals on the faceplate.
7. Connect each DC power cable to the appropriate external DC power source.
NOTE: For information about connecting to external DC power sources, see the instructions
for your site.
8. Switch on the external circuit breakers to provide voltage to the DC power source cable leads.
Observe the system LED on front of the router. If the DC power cable is correctly installed and
Figure 20 on page
105