Step 2 Lead each M10x40 bolt through a spring washer and flat washer in sequence, and then secure
the back mounting plate on the lower bracket until the tightening torque reaches 28 N·m, as
shown in Figure 10-3.
Figure 10-3 Installing a back mounting plate on a lower bracket
Step 3 Lead each M10x110 bolt through a spring washer, flat washer, and lower brackets on which the
back mounting plate is secured, and then tighten the bolts until the tightening torque of 28 N·m,
as shown in Figure 10-4.
Figure 10-4 Installing a backplane on a metal pole
DBS3900 (Ver.B)
Installation Guide
10 Outdoor Scenario with AC Power Supply (BBU Installed
in an OMB)
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