User's Manual

Optional Connections Nexus FT Strand Mount

3-4 044-05320 Rev A

Optional Connections

Alarms

Alarm signals from external sensors are received by an ALI or RCI which forwards them to the CU. The RCI is

used if the Nexus FT SM has an RCU, otherwise the ALI is used. The software on the CU can activate

acoustic or visual alarms or direct the alarm to the P33 alarm port for forwarding via an RCU through OM-

Online. Alarms can also be handled by the FON. Alarms are configured through OM-Online.

Commissioning

Before proceeding, carefully read the Safety section and check all connections made during the installation.

To fulfill the IP65 weather protective requirements, ensure cable strain relief bushings are properly tightened.

Also, ensure gaskets at cable inlets and on the cabinet are properly fitted and not damaged.

A Nexus FT SM can be configured locally with OM-Online by connecting a standard serial cable from the

COM port on the PC to the P31 PC port (RS-232) located to the right in the cabinet as shown in Figure 3-9.

The P31 PC port is described in Chapter 2. Details on using OM-Online are described in the OM-Online User

Manual.

Initial Startup

To complete the inital start-up of the Nexus FT SM, follow the steps listed in Table 3-3.

Table 3-2 Initial Statup Procedure

Passive Intermodulation (PIM) Testing

PIM is the non-linear effect of passive RF components in a desired RF transmission band. As higher per-

carrier transmit power levels are applied to duplexed passive RF networks, PIM becomes an increasingly

significant factor in potential receiver desensitization. A PIM tester may be used on the RF network prior to

turn-on and commissioning of the unit, but if a PIM tester is not available, the following may be used:

The following equipment is required to test for PIM:

❑ Anritsu Site eMaster or equivilent RF Spectrum Analyzer

❑ Agilent ESG4432B or equivilent Multi-Signal Generator (or commissioned BTS)

❑ Guarateed/calibrated PIM load capable of handling 20W composite power

❑ Low-PIM RF cable adaptors such as N-N female, Din male to N femaile, DIN-DIN, SMA-SMA

female, and N male to SMA female

❑ Installed and operational Nexus FT SM unit

❑ Installed passive RF network under test

❑ Torque wrenches for DIN and N connectors

Two different types of setup are available, depeding on equipment availability and testing methods.

Figure 3-10 shows PIM testing with two carriers over one Nexus FT SM, and Figure 3-11 shows PIM testing

with one carrier over each of two Nexus FT SMs.

Step Action

DRAFT