Installation guide

Chapter 3: Hardware Installation 23
Connecting the AC HFC Power Source
Connecting the M-eMTA From the HFC Plant
The M-eMTA has two AC inputs. Each input powers a corresponding power sup-
ply module. Note that the #1 input powers the #1 (left) power supply, and the
#2 input powers the #2 (right) power supply. Together, the two modules provide
power to the blades (up to six) installed in the M-eMTA under the worst case
loading conditions, and provides redundancy under normal load conditions.
It is recommended to feed each of the two M-eMTA’s 90 VAC inputs using a
power-extracting tap with two 480 mA @60c (750 mA @ 25c) current limiters. The
480 mA @60c (750 mA @ 25c) current limiter ensures that the M-eMTA has suffi-
cient power to meet the worst case loading conditions across temperature and
when operating at the end of the line where the input voltage may only be 70
VAC.
Follow these steps when connecting the M-eMTA from the HFC plant:
1. Connect the ground wire. For more information, see “Connect the Grounding
Wire” on page 14.
2. Verify that the bus bars are installed (connecting the surge protector to the
AC terminal block).
3. Ensure that the telephone, data, and the RF-Connector cables are properly
attached. For more information, see “Grounding and Cabling the Chassis” on
page 13.
4. Insert two (non-powered) AC twisted pair wires through the #1 coupling.
5. Connect the first twisted pair to the AC1 (left) terminal block (black = 1,
white = 2). Repeat the steps to attach the second twisted pair to the AC2
(right) terminal block.
CAUTION: The M-eMTA accepts an HFC network voltage of 70 to
90 VAC. Before installing, verify that the HFC network voltage is within
this range.
• Disconnect the power at the tap before performing this procedure.
• To turn the unit on and off; the power cables connecting the unit to the
HFC network power source acts as the disconnect device. Use only
one powering option at a time.
• To avoid personal injury, use the NEC guidelines and an ESD wristband
during the installation.
• The HFC network power source that connects to the M-eMTA needs
to comply with NEC Article 830.15.