Lencore G8254 User manual

OPERATIONS
MANUAL
TALK BACK COMMUNICATOR
Document number: 200-0011 rev C

table of contents
In the event of trouble, please contact:
Name:
Address:
Phone Number:
General operation: .................................................................................................................................. 1
Features and Capabilities:........................................................................................................................ 2
Installation Details:................................................................................................................................. 3
Overview................................................................................................................................................. 6
Wiring ..................................................................................................................................................... 8
Power and Network connections: ........................................................................................................ 9
UPS connection: .................................................................................................................................. 9
Configuring the System .......................................................................................................................... 10
Using the System.................................................................................................................................... 10
Paging ................................................................................................................................................. 10
Panic: .................................................................................................................................................. 10
Occupancy sensor:............................................................................................................................... 10
High Ambient Noise Sensing: ............................................................................................................... 10
Microphone peak detection:................................................................................................................ 11
Variable gain: ...................................................................................................................................... 11
Speaker relay:...................................................................................................................................... 11

RISK OF ELECTRIC SHOCK- DO NOT OPEN THE UNIT.
THERE ARE NO SERVICABLE COMPONENTS INSIDE.
IMPORTANT SAFETY INSTRUCTIONS
1) Read these instructions.
2) Keep these instructions.
3) Heed all warnings.
4) Follow all instructions.
5) Do not use this apparatus near water.
6) Clean only with dry cloth.
7) Do not block any ventilation openings. Install in accordance with the manufacturer's
instructions.
8) Do not install near any heat sources such as radiators, heat registers, stoves, or other
apparatus (including amplifiers) that produce heat.
9) Protect the power cord from being walked on or pinched particularly at plugs, convenience
receptacles, and the point where they exit from the apparatus.
10) Only use attachments/accessories specified by the manufacturer.
11)
12)
Refer all servicing to qualified service personnel. Servicing is required when the apparatus
has been damaged in any way, such as power-supply cord or plug is damaged, liquid has
been spilled or objects have fallen into the apparatus, the apparatus has been exposed to
rain or moisture, does not operate normally, or has been dropped.
The mains plug or appliance coupler shall remain readily operable.
WARNING To reduce the risk of fire or electric shock, do not expose this apparatus to rain
or moisture and do not expose to dripping or splashing and no objects filled with liquids,
such as vases, shall be placed on the apparatus

System: G8254 Talk Back Communicator
- At least one UPS and batteries should be used to provide secondary power supply for
emergency purposes
- The G8254 should be installed using:
1)
- The system is provided with a Communication Security Level 0, which indicates no Security
Level employed.
- The system is not to be used in buildings providing Suppression Service (Systems using Halon, etc).
Sprinkled systems are allowed.
Use four 6-32 x 1/2, black, stainless steel pan-head machine screws to mount the unit
to a junction box at least 2-1/8" deep.
Note: An NRTL (UL/ETL) listed double gang box must be used.

General operation:
The Talk Back unit is a two-way communications device that allows for dialog between a remote area, such
as a classroom or stairwell, and a central monitoring area, such as a security office. It is not a typical
intercom, and as such does not communicate between Talk Back units. The typical use case is one in
which there are speakers installed in the area of the Talk Back unit and the security office. When the user
presses the “Talk” button on the Talk Back unit a special page is generated on zone 100. The speakers in
the security office are part of zone 100 and will then play the audio from the Talk Back unit. After the user
releases the button, the page is ended. The security office then does a zone override page to the zone that
the Talk Back unit is in. In this way the security office page only goes to the speakers in the Talk Back area.
To prevent other Talk Back units from paging at the same time, the “Talk” button will go red on all other
Talk Back units, and paging is disabled on those units. Only one dialog can happen at any given time. At
the headend, the zone override page is handled by the six “Zone Override” buttons.
The Talk-back unit works with Lencore's G8220 Head-End rack unit.
1

Features and Capabilities:
•Page. Pressing and holding the TALK button initiates a page to a central monitoring area
(zone 100)
•Panic. Pressing the panic button sends a trigger to the headend to alert the security staff of an issue
in a particular area.
•Occupancy Sensor. Embedded in the unit is a Passive Infrared Sensor (PIR) that monitors
the area around the Talk Back unit and keeps a historical log of activity.
•High Ambient Noise Sensing. The Talk Back unit includes a microphone that is specially designed
to detect very loud noises such as gun shots or other abnormally loud noises.
•Microphone Peak Detection. Both microphones have peak detection circuits that allow
the headend to monitor peak values for a given time period.
•Variable gain. Both microphones have variable gain circuits that allow the headend to
choose whether to use standard gains or ultra-high sensitivity mode.
•Speaker Relay. The speaker relay connection goes to a special Lencore Speaker that is
relay activated.
2

Installation Details:
3
The Talk Back unit is installed in a standard 4x4 NRTL (UL/ETL) listed double gang switch box using four
6-32 x ½ black stainless-steel pan-head screws. A switch box is required as the 4 mounting screws line up
with holes that are only present on a switch box. The box needs to be at least 2-1/8” deep. The cabling must
exit the junction box on the lower right-hand corner of the bottom of the box. Sufficient cable service loop
must be present to allow the cables to be connected to the Talk Back unit and then fed out of the box as the
Talk Back unit is mounted. When an in-wall switch box is used, this extra cable can be easily fed into the
wall. If a surface installation is done there typically needs to be a pull box, j-box or other scheme employed
to allow for cable to be pulled in and out of the switch box during installation and removal. An example could
be a secondary 4x4 j-box below the Talk Back unit, connected to the switchbox with a suitable nipple.
The Talk Back units requires a 24v dc power feed from either a Lencore supplied HRP-150-24 power supply
or a Lencore PSM7A battery backed up 24v supply. With either supply a total of 15 units can
be fed off one supply (assuming 16AWG wire at 400 ft max from power supply to the last Talk Back unit).
The ground must be maintained on the Talk Back units, the same way Operating Platforms are wired.
In addition to power, the Talk Back sits on the system databus, and as such has a data in and data out
connection. Data cable: The maximum length of the Data cable is 3000 feet from the head-end to the LAST
device connected to the Data cable. A device can be an OP or talk-back module. The distance from talk-
back to talk-back is not relevant if the previous statement is met. To extend the data cable, adding a router
after the LAST device allows the Data cable to run another 3000 feet from the router.
See the flow diagram below (figure 1).

Flow diagram
4

Typical 4x4 junction box:
Talk Back mounted in the junction box:
5

Overview
Front Plate
1. PANIC button
The panic button can be pressed to
send a page alert to the central
monitoring area.
2. TALK button
The talk button can be pressed to
make a page to the central monitoring
area.
3. Motion Sensor
The motion sensor senses motion in the
room and can be monitored by the central
monitoring area.
4. Microphone
While pressing the talk button, speak into
the microphone to make a page to the
central monitoring area.
6