Modem Installation And Maintenance Practice

Table Of Contents
Section 3, Installation - Ground and Power Connections
61179605L5-5B 3-7
Power Connection
The Total Access 1240 uses a four-point terminal block (see Figure 3-5) to accept the
–48 VDC and –48 VDC RET leads.
Figure 3-5. Four-point Terminal Block
NOTE
If a non-redundant power configuration is to be implemented, use
the connections marked –48 VDC A and –48 VDC A RET.
To connect the power source, perform the following steps:
1. With the power disconnected at the source, remove approximately 1/4-inch of insulation
from the ends of both power wires.
NOTE
ADTRAN recommends an external fuse rated between 1.5 to 2.0
amps.
2. Using a small flat-head screwdriver, loosen the setscrews on the top of the terminal block.
3. Insert the bare wire into the opening on the front of the terminal block.
4. While holding the wire in place, tighten the setscrew until the wire is secure.
5. Repeat this procedure until all power leads are connected, making sure that the wires are
connected using correct polarity according to the labeling on the unit above the terminal
block.
6. Apply power to the Total Access 1240 and test the voltage and polarity on the terminal
block using the tops of the setscrews as test points.
-48 VDC B RET
-48 VDC A RET
-48 VDC A
-48 VDC B