CommScope Drop Cable - Manual (Page 48)

Overview
Multiple Dwelling Units (MDUs) have a more strict set of rules for cable installation than single family residences.
Service is dropped from the tap to the building like a residential installation, either aerially (see Section 6) or un-
derground (see Section 7). However, the cable is usually run to some sort of interconnect box which allows the
service provider to secure the connection and prevent tampering. This box may be inside or outside the building.
A building with two or more apartments or condominiums is not considered to be a
single-family residence and is governed by commercial building and safety regulations.
For instance, you may need to use riser-rated cables instead of CATV rated residential
cables. A general rule of thumb is if the cable penetrates the floor (if it runs vertically
between floors), then you must use a riser-rated cble (CATVR for coax, CMR for UTP,
OFNR for fiber). The riser cable is then run horizontally to the outlet (while you may use
a lower rated cable for horizontal runs, the extra time and cost of termination outweighs
the cost difference between the cables). You may use CATV cable inside metal conduit to
pass between floors, though using a riser-rated cable is much easier.
Signal Amplification
Another issue to consider is amplification. The signal being carried by the drop could be split literally dozens of
times, thus decreasing its strength to the point where it is no longer viable. This is solved by installing a line ampli-
fier before the crossconnection. While most amplifiers are powered by the voltage in the cable, some require con-
nection to 110/120V power. Consult the directions from the manufacturer for specific powering instructions.
The run from the crossconnect to the apartment could be several hundred feet. You may wish to consider upgrad-
ing your cable (example: from F11 to QR 320) or installing another line amplifier along the route.
Article 830 Considerations
The same rules apply concerning aerial distances (page 5.1), burial depth (page 6.1) and use of raceway or
conduit within 8 ft (2.5 m) of the ground as residential installation. Article 830 also permits you to transition up to
50 ft (15.2) meters of cable to meet an interior-mounted NIU. Longer runs require that the cable be run in metal
conduit or within the wall like electrical wiring.
tech tip:
review
section 9
for complete
advice on
running
cables inside
a structure
10.1 Multiple Dwelling Units (MDUs)
Overview