Off-Premises Range Extender; Electromagnetic Interference Filters; System Alarms; Trouble Alarm - AT&T MERLIN LEGEND Release 3.1 System Manager's Manual

Power-Related Hardware

Off-Premises Range Extender

An Off-Premises Range Extender (OPRE) is used for off-premises extensions up
to 5.2 miles from the control unit.
146A and 147A Surge Protectors
If you live in an area prone to heavy lightning and/or power surges, the control
unit may require surge protectors. The control unit's power supply has built-in
protection, so extra protectors are not usually necessary. It is the responsibility
of the local telephone company to provide primary protection on the outside
lines where they connect to the control unit and to ensure that these protectors
are properly grounded. If the telephone company line protector is properly
grounded and bonded to the AC power ground, most lightning damage is
prevented.
When your system is installed, your AT&T representative sees that you have the
necessary protection. If electrical conditions change, contact your
representative and ask for advice.

Electromagnetic Interference Filters

Your AT&T representative will recommend these filters for certain environments
where electric motors, radio transmitters, or other radio-frequency generating
equipment may interfere with telephone reception.

System Alarms

An alarm condition detected by the system can cause the control unit to
activate an alarm device on a loop-start port. When the contacts close, a signal
is passed on to a Universal Paging Access Module (UPAM) and then to an
external alert. Alerting devices can be a strobe, horn, bell, or chime.

Trouble Alarm

Your system operator consoles have programmed Alarm buttons to let you know
if there is a problem with the system. An external bell or light can be attached to
a console to supplement the button. If this is not enough notice of a system
problem, an AT&T technician can use a loop-start line jack and a UPAM to
attach a bell or strobe light to the system.

Power Failure Alarm

Your AT&T technician can use a ground-start or loop-start power-failure transfer
(PFT) telephone jack to attach an alerting device that will go off during a power
failure. You can connect a PFT telephone to this jack when the jack is
connected for a power failure alarm.
System Components
3–45