ARRIS TM508 Installation Guide - Manual (Page 29)

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TM508/TM512 Installation Guide Release 5 Standard 1.2 Mar 2007
If the Telephony Modem is intended to provide data services, Ethernet
lines from subscriber units must be run to a switch or hub in the wiring
closet. The switch or hub must have at least one free connection for the
Telephony Modem.
Grounding
Requirements When using AC power, a grounded 3-prong AC outlet provides safety
ground. When using a SELV DC power supply, such as the Local Bat-
tery Backup Supply (part number 718115K), safety ground is not
required.
The grounding lug on the Telephony Modem provides chassis ground,
and can be used if desired. Use #12 AWG wire to connect the ground-
ing lug to the AC building ground.
The coax ground should be tied to AC building ground per NFPA 70
(National Electrical Code) Article 820 requirements.
Tools You need a small flat-blade screwdriver to secure serial, telemetry, and
DC power cables.
You need a #1 Phillips screwdriver to secure the ground wire to the
grounding lug.
A torque-limiting wrench can be used to secure RF cables.
Action Follow these steps to connect cables to the Telephony Modem.
1 (optional) Attach a ground wire between the Telephony Modem
ground lug and a proper earth ground. For best results, minimize
sharp bends or kinks between the Telephony Modem and the
ground.
2 Connect the RF cable to the Network RF connector, and tighten to a
torque pressure of 17 to 23 Kg-cm (15 to 20 in-lb.).
Note: If a torque-limiting wrench is not available, tighten the con-
nector by hand, then tighten a further 1/8 to 1/4 turn with a wrench.
3 Insert one end of the telephony cable through the Velcro® strap on
the punch-down block connector, plug the cable into the connector,