Guardian Telecom ExP-TBA Guide

7552 - 10th Street N.E. Calgary, Alberta, Canada T2E 8W1
Industrial Communications Worldwide
Explosion Proof Talk/Back Wall Station
Model ExP-TBA
Installation & Operation
P005615 Rev. E 080220 2/21/2008 1:43 PM
Ph: 403.258.3100 \ email:[e-mail] \ www.guardiantelecom.com

Guardian Telecom Inc.
Installation and Operation
Model ExP-TBA
Page 2
Table of Contents
Package Contents.................................................................................2
Overview ...............................................................................................3
EXP-TBA Features................................................................................3
Installing the EXP-TBA..........................................................................6
Switching between Operating Modes:...................................................7
Operation...............................................................................................7
Controls.................................................................................................9
Engineering Specifications..................................................................10
Warranty..............................................................................................11
Disclaimer............................................................................................11
Warning...............................................................................................11
Service Telephone Number.................................................................11
Feedback.............................................................................................11
Guardian Product Return ....................................................................12
Table of Figures
Figure 1 - Features................................................................................4
Figure 2 - Dimensions ...........................................................................4
Figure 3 - Mounting ...............................................................................5
Figure 4 - Typical Installation ................................................................5
Figure 5 - Circuit Board Layout..............................................................9
Figure 6 - Control Pots and Wiring........................................................9
Package Contents
(1) EXP-TBA Master Station
(12) Faceplate Bolts
(2) Tubes of Lubricant
(1) Installation & Operation Manual

Guardian Telecom Inc.
Installation and Operation
Model ExP-TBA
Page 3
Overview
Talk Back System EXP-TBA
The model EXP-TBA is an intercom system designed for use in situations where frequent
communication between two stations is required. The system is particularly well suited to
drilling rig operations. The system utilizes a remote Slave loudspeaker in dual roles, to
broadcast messages from the Master Station and to act as a microphone to pick up and
transmit messages back to the Master Station. The Master Station has a microphone on the
faceplate which is activated when the Push-To-Page button on the faceplate is pressed. An
option is for the connection of a remote foot switch or hand operated button switch, which
when activated will cause the Master Station loudspeaker to act as a microphone.
The EXP-TBA system has two possible operating modes:
1. Hands Free Talk-Back Mode: In this mode the Slave speaker is always configured
as a microphone sending any sound in the area back to the Master Station speaker,
except when the Master Station is activated to transmit. If desired a push button can
be installed near the Slave speaker, which when pressed will cause a ringing signal
to be heard over the Master Station speaker. The ringing signal will be heard even if
the Master Station speaker volume is turned down.
2. Push-To-Talk Mode: In this mode neither the Master Station speaker nor the Slave
speaker is normally in transmit mode. A push button is required at the Slave speaker
to put the speaker into transmit mode. The button must be held in for the duration of
the call.
EXP-TBA Features
Enclosure and Faceplate
•copper free cast aluminum - powder coated
Master/Slave Operation
•only one master station required
Post Announcement Tone
•optional – jumper on circuit board
Slave Operator Ring Tone To Master Station
•optional – requires a push button switch at the slave speaker location
•ring tone volume adjustable (internal)
Page Switch
•page switch on faceplate of enclosure
•option for external hand or foot switch
Master Microphone
•on faceplate of master station
•option for use of master speaker as microphone
Controls
•separate master and slave speaker volume controls on faceplate
Power Requirement
•24 VDC or 24/120/230 VAC

Guardian Telecom Inc.
Installation and Operation
Model ExP-TBA
CABLE ENTRANCES
VOLUME CONTROL
MASTER SPEAKER
1" NPT
CONNECTOR
FOR SPEAKER
ENTRANCE
VOLUME CONTROL
BUTTON
PUSH TO TALK
SLAVE SPEAKER
STATION MICROPHONE
ID LABEL
CERTIFICATION LABEL
WARNING LABEL CAST ALUMINUM
ENCLOSURE WITH
POWDERCOAT
FINISH
1 1/2" NPT
Figure 1 - Features
15.7" [398mm]
10.0" [254mm] 6.7" [171mm]
Figure 2 - Dimensions
Page 4

Guardian Telecom Inc.
Installation and Operation
Model ExP-TBA
Figure 3 - Mounting
Figure 4 - Typical Installation
Page 5
14.67" [373mm]
7.25" [184mm] Ø0.4" (Ø10mm)
4 PLACES
POWER SUPPLY
24VDC, 120/240VAC
OPTIONAL REMOTE
HAND/FOOT SWITCH
MASTER STATION SPEAKER
MASTER STATION
E
O
V
M
L
U
R
A
M
E
S
T
O
L
U
M
V
V
S
L
A
E
E
SWITCH
EXPLOSION PROOF SPEAKER
SLAVE SPEAKER
OPTIONAL PTT/RINGTONE

Guardian Telecom Inc.
Installation and Operation
Model ExP-TBA
Page 6
Installing the EXP-TBA
The master station is approved for use in hazardous areas. The speakers
used with the system may or may not be approved, check the labels on the
speakers for ratings.
Follow all local codes and requirements when installing the EXP-TBA Intercom
System.
Mount the Master Station and speakers.
Wire the system in accordance with local codes. The speaker cable used in the
system requires either two or four 18 AWG, shielded conductors – depending on the
system configuration. Power cable requires either two 14AWG conductors (DC), or
three 14AWG conductors (AC).
See: Figure 4 -
Typical Installation
If necessary adjustments to potentiometers can be made during commissioning to
suit existing conditions. In order to facilitate making adjustments on the circuit board
remove the faceplate, offset it to one side or the other of the enclosure and then
secure it temporarily to the enclosure with two bolts.
See: Figure 5 - Circuit
Board Layout
Post announcement tone jumper: The post announcement tone is very useful in a
half duplex intercom system. A beep-tone will be heard when the push to talk switch
is released, the tone will signify that the transmission from the master station is over.
If in PTT mode, the tone will also be heard when transmission from the slave
speaker is over. Jumper JP1 on the circuit board is used to enable or disable the
post announcement tone. To enable the post announcement tone set the jumper to
the TONE position, to disable the tone set the jumper to the OFF position.
Microphone input level Potentiometer: This potentiometer is referenced R24, and
labeled as MIC INPUT ADJ. It is used to control the audio signal from the
Microphone input and the Master speaker as microphone input.
Slave Station Talk-Back input level Potentiometer: This potentiometer is
referenced R43, and labeled as TALKBACK INPUT ADJ. It is used to control the
input audio signal from the Slave Speaker.
Ringer Volume Adjusting Potentiometer: This potentiometer is referenced R54,
and labeled as RING VOL. It is used adjust the volume of the ring tone and the beep
tone by controlling the input audio signal.
Master Station speaker Attenuation Potentiometer: This potentiometer is
referenced R21, and labeled as ATTEN LEVEL. It is used to control the amount of
attenuation to the Master Station speaker (if the master station microphone is used),
when the Push-To-Page switch is activated. It should be adjusted when the Push-
To-Page switch is engaged, to a level that will not cause acoustic feedback
(howling), with the volume control on the front of the faceplate turned to maximum.
Important: Speakers should be mounted as close as possible to users, since they
serve as microphones as well. This will reduce the amount of ambient noise
entering the speech transmission.
Apply a bead of lubricant to the machined surface of the housing.
Replace the faceplate ensuring that the connector is properly seated.
Torque faceplate bolts to 13.5 ft. lbs. (18 Newton-Meters).
Tip: The lubricant
acts as a seal to
prevent water and
dust from entering the
enclosure.

Guardian Telecom Inc.
Installation and Operation
Model ExP-TBA
Page 7
Switching between Operating Modes:
When powered up the Talk Back System will operate in the Slave Hands
Free mode. In order to avoid opening up the EXP-TBA to switch operating
modes the following procedure is used to toggle to the Slave PTT mode and
vice versa.
1) Press the Page-To-Page switch and hold it for longer than 5
seconds (by counting from 1 to ten), then release the switch for a
break time from 1/2 a second to 3 seconds.
2) Press the Push-To-Page switch ten times. Each time hold the
switch from 1/2 a second to 2.5 seconds then release it for a break
time from 1/2 a second to 3 seconds..
3) Push the Push-To-Page switch and hold it for longer than 5
seconds (by counting from 1 to ten). Then release the switch.
4) If the sequence is correct the system will switch its present
operating mode to the other operating mode. Three beep tones will
be heard over the Master Station speaker if the mode switching
occurs.
Note: If power is lost after the system has been switched to Slave PTT mode it
will revert back to Slave Hands Free mode when power is restored.
Operation
1. Hands Free Talk Back Mode:
In Hands Free Talk Back mode the Master Station speaker is normally on and
the Slave speaker is functioning as a microphone.
Faceplate Push-To-Page switch: Without any switches activated any sound
in the Slave speaker area will be heard on the Master Station speaker. When
the Push-To-Page switch (located on the EXP-TBA faceplate) is activated the
Master Station speaker will be turned on – with attenuation to reduce the
possibility of acoustic feedback, the Slave speaker will also be turned on.
This condition will occur even if the remote Master Station or Slave switches
are activated, since the Push-To-Page switch has priority.
Remote Master Station Switch – (optional): This can be a foot operated or
a hand operated button switch. It will activate the Master Station when it is
pushed and when the Push-To-Page switch is open. In this condition the
Master Station speaker is converted into a microphone. The Slave speaker is
turned on to broadcast the message sent from the Master Station.
Slave Station Switch – (optional): If an optional push button switch is
installed next to the Slave speaker a ring tone will be heard on both the
Master Station speaker and the Slave speaker when the button is pressed.
This will occur even if the Master Station speaker volume control is turned
down and will alert persons in the vicinity of the Master Station.

Guardian Telecom Inc.
Installation and Operation
Model ExP-TBA
Page 8
2. Press-To-Talk Mode:
In Press-To-Talk Mode the Master Station speaker and the Slave speaker are
normally off. A push button is required at the Slave speaker to put the
speaker into transmit mode. The button must be held in for the duration of the
call.
Microphone Push-To-Page Switch: When the Push-To-Page switch
(located on the EXP-TBA faceplate) is activated the Master Station speaker
will be turned on – with attenuation to reduce the possibility of acoustic
feedback, the Slave speaker will also be turned on. This condition will occur
even if the remote Master Station or Slave switches are activated, since the
Push-To-Page switch has priority.
Remote Master Station Switch – (optional): This can be a foot operated or
a hand operated switch. It will activate the Master Station when it is pushed
and when the Push-To-Page switch is open. In this condition the Master
Station speaker is converted into a microphone. The Slave speaker is turned
on to broadcast the message sent from the Master Station.
The Slave Station Switch: When the Slave station switch is pressed, the
Slave speaker is converted into a microphone. The Master Station speaker
will be turned on to receive the message from the Slave station. This condition
is valid as long as neither the Push-To-Page nor Master Station remote
switches are activated.
Button priorities are:
1. Faceplate Push-To-Page switch.
2. Master Station remote switch (either a hand operated button or a foot
switch).
3. Slave speaker switch.
Speaker Volume Controls:
The Master Station speaker Volume Control and The Slave Speaker Volume
Control knobs are located on the faceplate and can be adjusted to provide a
comfortable sound level.
The Master Station speaker Volume Control: The Master Station speaker
Volume Control knob is used to adjust the volume on the Master Station
speaker. This should be done with input from the Slave speaker, since
activating the Push-To-Page switch will attenuate the Master Station speaker
volume.
The Slave Speaker Volume Control: The Slave Speaker Volume Control
knob is used to adjust the volume on the Slave Speaker.

Guardian Telecom Inc.
Installation and Operation
Model ExP-TBA
FROM FACEPLATE
SUB ASSEMBLY
TRANSFORMER
Master Speaker +
1
External PTT Switch -
External PTT Switch +
Master Speaker Ground
Master Speaker -
J1
DETAIL A
4
5
2
3
T-10-8138900
1
TONE/OFF
JP1
MASTER SPEAKER ATTENUATION LEVEL
ADJUSTMENT
TRANSFORMER
MASTER SPEAKER/
SWITCH TERMINAL
DETAIL A
R21
FROM SMALL
J6
T-10-8138900
FROM SMALL
J4
J1
Slave Speaker +
Slave Speaker -
Slave Speaker Ground
PTT/Ring Switch +
PTT/Ring Switch -
SLAVE SPEAKER/SWITCH TERMINAL
RING VOLUME
ADJUSTMENT
R54
1
J3
DETAIL B
Neutral
Ground
Hot
2
3
1
J7
DETAIL C
4
5
2
3
J7
DETAIL C
FROM LARGE TRANSFORMER TRC-255-C12
TERMINALS
INPUT ADJUSTMENT
R24
MIC INPUT
ADJUSTMENT
R43
DETAIL B
AC POWER
J3
24V AC/DC POWER INPUT
J5 J2
SLAVE SPEAKER TALK BACK
Figure 5 - Circuit Board Layout
Controls
Adjusting Pots: PCB Mounted:
•R21: Master Station speaker attenuation control.
•R24: Microphone input volume control (internal mic. or speaker as mic.)
•R43: Slave Speaker talk/back input volume control.
•R54: Ring tone volume control.
Faceplate Mounted:
1) Master Station speaker volume control.
2) Slave Speaker volume control.
Post announcement tone jumper:
JP1; ON position: Post announcement enabled.
JP1; OFF position: Post announcement disabled.
Figure 6 - Control Pots and Wiring
Page 9

Guardian Telecom Inc.
Installation and Operation
Model ExP-TBA
Page 10
Engineering Specifications
ELECTRICAL
POWER REQUIREMENT 24VDC; 120V/230VAC, 50/60 HZ
POWER SUPPLY FUSE 24VDC -1AMP,120VAC -0.50A, 230VAC -0.25 AMP
SLOW BLOW,2AG
AUDIO OUTPUT FUSES 250V, 0.75A, SLOW BLOW,2AG
AUDIO AND CONTROL INPUTS
MASTER INTERNAL MICROPHONE 600 OHMS,750mV RMS MAXIMUM
EXTERNAL PTT SWITCH (OPTIONAL) DRY CONTACT SPST SWITCH
AUDIO OUTPUTS
MASTER SPEAKER CHANNEL 70V LINE,10 WRMS
SLAVE SPEAKER CHANNEL 70V LINE,10 WRMS
ENVIRONMENTAL
TEMPERATURE -40°TO +60°C(-40°TO +140°F)
HUMIDITY 0–95% RH NON CONDENSING
MECHANICAL
BODY CONSTRUCTION COPPER FREE CAST ALUMINUM
NET WEIGHT 27 LBS./12.3 KG
DIMENSIONS (W X HX D) 10 X 15.7 X 6” (254 X 398 X 152 MM)
STANDARD MOUNTING VERTICAL WALL
CABLE ENTRANCES TWO 1½” NPT OPENINGS ON BOTTOM SURFACE
ONE 1” NPT OPENING ON TOP SURFACE
COMPLIANCE
CSA (US AND CANADA) CLASS I, DIVISION 1, GROUPS B,C &D
CLASS II, DIVISION 1, GROUPS E,F &G
CLASS I, ZONE 1, GROUP IIB+H2T6
ENCLOSURE TYPE 4X /IP56

Guardian Telecom Inc.
Installation and Operation
Model ExP-TBA
Page 11
Warranty
Guardian Telecom warrants your product to be free of defects in material and workmanship for a period
of one year. Guardian Telecom will repair or replace any defective unit that is under warranty free of
charge.
This warranty is null and void if any non-authorized modifications have been made to this product, or if
it has been subjected to misuse, neglect, or accident. This warranty covers bench repairs only; such
repairs must be made at Guardian Telecom or an authorized service depot. Guardian Telecom is not
responsible for costs incurred for on-site service calls, freight, or brokerage.
Guardian products have been quality tested and are in full working order when shipped from the
factory, Shipping damage should be claimed on the carrier.
A return authorization must be obtained prior to warranty claims or repairs.
Disclaimer
The products covered by this manual are designed for use in Industrial Environments and/or Hazardous
Locations. Due to the range of possible applications the manufacturer will not be responsible for
damages or losses of any kind suffered as a result of the use of this product, including consequential
damages. Warning
High voltages may be present in this product. Ensure that power is removed before installing,
performing maintenance or repairs.
Service Telephone Number
1-800-363-8010 (North America)
Guardian Telecom provides a customer service telephone number which is toll-free within North
America. If you need assistance when installing or operating this product, please call the toll-free
telephone number between regular business hours (8:00AM-5:00PM), Mountain Standard Time. If you
are calling outside of regular business hours, please leave a detailed message, and a member of
Guardian Telecom’s Service Department will return your call as soon as possible. If your product
requires service, Guardian personnel will supply you with an RMA (return materials authorization)
number over the telephone or through our web site product return page. This number must be included
with your return address and the name of the person to contact.
Guardian Telecom Inc.
7552 - 10th Street N.E.
Calgary, Alberta, Canada T2E 8W1
Toll-free 1-800-363-8010 in North America
Ph. [phone]
Fax. [phone]
www.guardiantelecom.com
Feedback
Guardian Telecom continually strives to make reliable, durable, and easy to use products. If you, as an
installer or user of our equipment, have any suggestions for improvements to this or any of our products
or documents, including this manual, we would appreciate hearing from you.

Guardian Telecom Inc.
Installation and Operation
Model ExP-TBA
Page 12
Guardian Product Return
Guardian products have been quality tested and are in full working order when shipped from
the factory, given the rugged nature of these products shipping is not expected to damage a
unit. In the unlikely event of a malfunction, Guardian follows the three step procedure below.
Step I - On-Site Correction
•The most common source of difficulties with a new product is improper installation in one of
two ways: incorrect wiring connections or connection to an incorrect power source.
•Product wiring needs to be properly connected to the on-site wiring. Correct wiring
instructions are shown in the user manual included with the product.
•Connecting a telephone to a standard power source, rather than tip & ring, will blow the
telephone’s internal, user-replaceable fuse. In the event of fuse burn-out, disconnect the
telephone from the power source, replace the fuse, and reconnect following the wiring
diagrams provided with the product.
Step II - Return Materials Authorization (RMA)
•When a product has been installed following user manual instructions, and the unit fails to
operate, the user must contact Guardian Telecom to obtain authorization to return the
product. This can be done by completing a RMA form online at
www.guardiantelecom.com, or by calling the service telephone number given in this
manual.
•After providing information on the product, the owner and the nature of the problem,
Guardian will issue a RMA number, to be shown on documentation returned with the
product.
•In addition to the RMA number, shipping documents should include name, address and
telephone number of the owner along with contact information for the person responsible
for the repair and/or the user who identified the malfunction.
•(Where a product is being returned for repair from outside of Canada, customs
documentation must show the product’s serial number, date of export [date of purchase],
and a notation that the equipment is: “Canadian goods returning.”)
Step III - Factory Authorized Service
•Once received, each product is carefully inspected and tested. If the product is under
warranty, repairs are completed and the product returned to the owner, generally within
five working days of receipt by the factory.
•A product that has been subjected to misuse, neglect or accident or is beyond the warranty
period will be evaluated. The service department will provide the owner’s representative
with a repair cost estimate. Once approved, repairs are completed and the product
returned, generally within five working days.

Guardian Telecom Inc.
Installation and Operation
Model ExP-TBA
Page 13
Notes:
Model No.
Part No.
Serial No.
Date of Purchase

Guardian Telecom Inc.
7552 - 10th Street N.E.
Calgary, Alberta, Canada T2E 8W1
Toll-free 1-800-363-8010
Ph. [phone]
Fax. [phone]
www.guardiantelecom.com
E-mail: [email protected]
(Click to open message box)
Industrial Communications Worldwide
© Guardian Telecom Inc. 2008