System Sensor i3 Series, i3 2WTR-B, i3 2WTA-B, i3 4WTR-B, i3 4WTA-B Installation And Maintenance Instructions Manual

INSTALLATION AND MAINTENANCE INSTRUCTIONS

WARNING

Series

Photoelectric Smoke Detector

2-Wire: 2WTR-B (Form C Relay), 2WTA-B (Sounder)
4-Wire: 4WTR-B (Form C Relay), 4WTA-B (Sounder)
4WTAR-B (Form C Relay, Sounder), 4WITAR-B (Isolated Thermal, Form C Relay, Sounder)

Before Installing

Please read thoroughly System Sensor Application Guide:
System Smoke Detectors, which provides detailed information

on detector spacing, placement, zoning, wiring, and special
applications. Copies are available on System Sensor’s web site:
www.systemsensor.com.

NOTICE: This manual shall be left with the owner/user of this
equipment.

IMPORTANT: This detector must be tested and maintained regu­larly following National Fire Protection Association (NFPA) 72
National Fire Alarm Code requirements. At a minimum, cleaning
should be performed annually.

General Description

Models 2WTR-B and 2WTA-B are 2-wire photoelectric smoke
detectors; models 4WTR-B, 4WTA-B, 4WTAR-B, and 4WITAR-B
are 4-wire photoelectric smoke detectors. All models incorpo­rate a state-of-the-art optical sensing chamber and an advanced
microprocessor. The microprocessor allows the detector to auto­matically adjust its sensitivity back to the factory setting when
it becomes more sensitive due to contaminants settling in its
chamber. In order for this feature to work properly, the chamber
must never be opened while power is applied to the smoke detec­tor. This includes cleaning, maintenance or screen replacement.
All models also feature a restorable, built-in, fixed temperature
(135°F) thermal detector and are also capable of sensing a freeze
condition if the temperature is below 41°F.

Models 2WTA-B, 4WTA-B, 4WTAR-B, and 4WITAR-B contain a
piezoelectric horn which generates the ANSI S3.41 temporal pat­tern in an alarm condition. All detectors on a zone will sound
when the power supply to them is reversed. The RRS-MOD can be
used for the power supply reversal function. The RRS-MOD also
enables all the detectors’ sounders on a zone to be synchronized
and allows the zone to be silenced from the panel by entering the
alarm silence key at the keypad.

The detector that initiated the alarm condition will have its red
LED and Form C relays (if applicable) latched until reset by
panel.

The model 4WITAR-B photoelectronic smoke sensor is isolated
from the fixed-temperature heat sensor, providing a self-resetting,
local audible smoke alarm that does not alarm at the panel. Only
the fixed-temperature heat sensor will cause the 4WITAR-B to ini­tiate an alarm at the panel and the relay to change its state.

NOTE: In order for all i3 sounder detectors on a loop to sound
when the panel alarms, the supply voltage polarity must be
reversed. A reversing relay, System Sensor model number
RRS-MOD, must be used. The RRS-MOD is designed to allow
all i3 Series detectors in the same loop to sound when one of
the detectors goes into alarm. In addition, the RRS-MOD will

D100-99-00 1 I56-2170-04R

synchronize all of the i3 Series sounder smoke detectors on
the loop. Some panels may require the use of programmable
outputs. Refer to System Sensor literature for further informa­tion on the RRS-MOD.

All i3 Series detectors are designed to provide open area protec­tion. Two-wire models must be used with compatible UL Listed
panels only.

When used with an “i3 Ready” control panel or the i3 Series 2W­MOD2 module (refer to installation manual), the 2WTR-B and
2WTA-B are capable of generating a “maintenance needed” sig­nal. The 2W-MOD2 can indicate a need for cleaning, replacement,
or a freeze trouble at the control panel or module.

The 2W-MOD2 has replaced the previous model number 2W­MOD. To ensure proper remote maintenance signaling capabili­ties, do not use the 2W-MOD with i3 model numbers 2WTR-B and
2WTA-B.

Installation of the 2WTR-B, 2WTA-B, 4WTR-B, 4WTA-B, 4WTAR­B, and 4WITAR-B detectors is simplified by the use of a mounting
base that may be pre-wired to the system, allowing the detector
to be easily installed or removed. The mounting base installation
is further simplified by the incorporation of features compatible
with drywall fasteners.

Two LEDs on the detector provide a local visual indication of the
detector’s status:

Table 1: Detector LED Modes

| Green LED | Red LED
Power-up | Blink 10 sec | Blink 10 sec
Normal (standby) | Blink 5 sec | —
Out of sensitivity | — | Blink 5 sec
Freeze Trouble | — | Blink 10 sec
Alarm | — | Solid

During an initial power-up delay, the red and green LEDs will blink
synchronously once every ten seconds. It will take approximately 80
seconds for the detector to finish the power-up cycle (see Table 2).

Table 2: Power-up Sequence for LED Status Indication*

Condition | Duration
Initial LED Status Indication | 80 seconds
Initial LED Status Indication
(if excessive electrical noise is present) | 4 minutes

*Refer to Electrical Specifications for start-up time in conjuction with panel alarm
verification.

NOTE: If, during power-up, the detector determines there is exces­sive electrical noise in the system such as those caused by improp­er grounding of the system or the conduit, both LEDs will blink for
up to 4 minutes before displaying detector status (see Table 2).

3825 Ohio Avenue, St. Charles, Illinois 60174

1-800-SENSOR2, FAX: [phone]

www.systemsensor.com

|

After power-up has completed and the detector is functioning

SNAP OFF TAB
FOR TAMPER LOCK

TAMPER
RELEASE TAB

DIRECT MOUNT
HOLES

2-WIRE
ZONE

2-WIRE
CONTROL
PANEL

+

–

(5)

RA –

(4)

RA +

(3)

– IN/OUT

(2)

+ OUT

(1)

+ IN

RA400Z

EOL
RESISTOR

OPTIONAL
RELEASING
DEVICE

(6) NC

(7) C

(8) NO

NOT INCLUDED ON
2WTA-B MODEL

normally within its listed sensitivity range, the green LED blinks
once every five seconds. If the detector is in need of maintenance
because its sensitivity has shifted outside the listed limits, the red
LED blinks once every five seconds. When the detector is in the
alarm mode, the red LED latches on. The LED indication must not
be used in lieu of the tests specified under Testing. In a freeze
trouble condition, the red LED will blink once every 10 seconds
(refer to Table 1).

To measure the detector’s sensitivity, the i3 Series Model SENS­RDR Infrared Sensitivity Reader tool (see Figure 4) should be used.
Refer to instructions manual D100-98-00 for the proper use of the
SENS-RDR.

Models 2WTR-B and 2WTA-B also include an output that allows an
optional Model RA400Z Remote Annunciator to be connected.

Mounting

General spacing guidelines are 30′× 30′, with each detector cover­ing 900 ft2 under maximum conditions.

Consult NFPA 72, the local Authority Having Jurisdiction (AHJ),
and/or applicable codes for specific information regarding the
spacing and placement of smoke detectors.

Each i3 Series detector is supplied with a mounting base that can
be ceiling- or wall-mounted:

1. To a single gang box, or

2. To a 31⁄2-inch or 4-inch octagonal box, or

3. To a 4-inch square box with a plaster ring, or

4. Direct mount or to ceiling using drywall fasteners.

Figure 1: Mounting of Detector

Figure 2: Tamper-Resistant Feature

S0109-00

Wiring Installation Guidelines

All wiring must be installed in compliance with the NFPA 70,
National Electrical Code, applicable state and local codes, and any
special requirements of the local Authority Having Jurisdiction.

Proper wire gauges should be used. The conductors used to con­nect smoke detectors to the alarm control panel and accessory
devices should be color-coded to reduce the likelihood of wiring
errors. Improper connections can prevent a system from respond­ing properly in the event of a fire.

The screw terminals in the mounting base will accept 14–22
gauge wire. For best system performance, all wiring should be
installed in separate grounded conduit; do not mix fire alarm
system wiring in the same conduit as any other electrical wiring.
Twisted pair may be used to provide additional protection against
extraneous electrical interference.

Wire connections are made by stripping approximately 1⁄4-inch of insu-
lation from the end of the feed wire, inserting it into the proper base
terminal, and tightening the screw to secure the wire in place. Do not
put wires more than 2 gauge apart under the same clamping plate.

Two-Wire Compatibility

System Sensor two-wire smoke detectors are marked with a com­patibility identifier located on the label on the back of the product.
For two-wire models 2WTR-B and 2WTA-B, connect detectors only

S0121-00

The i3 Series heads and bases are keyed so that all heads will only fit
into their respective bases. One model 4-wire relay base will accept
the 4WTR-B, 4WTAR-B and 4WITAR-B detector heads and no others.
The 2WTR-B, 2WTA-B and 4WTA-B will only fit into their respective
mounting bases and no others. The heads and bases are clearly iden­tified as either 2-wire or 4-wire. When mounting the i3 Series, ensure
that the head is mounted to the correct base, and the test switch is
aligned with the tamper release tab.

to compatible alarm control panels as identified by System Sensor’s
two-wire compatibility chart, available at www.systemsensor.com.

NOTE: Models 2WTR-B and 2WTA-B are not to be installed

on initiating circuits containing other makes/models
of smoke detectors.

NOTE: Style D initiating circuits require the use of a 2W-

MOD2 for models 2WTR-B and 2WTA-B

Wiring Diagrams
Figure 3a: Wiring Diagram, 2WTR-B and 2WTA-B

Tamper-Resistant Feature

The i3 Series detectors include a tamper-resistant feature that pre­vents removal from the mounting base without the use of a tool.
To engage the tamper-resistant feature, cut the small plastic tab
located on the mounting base (Figure 2), and then install the detec­tor. To remove the detector from the base once it has been made
tamper resistant, use a small screwdriver to depress the square
tamper release tab, located on the skirt of the mounting base, and
turn the detector counterclockwise.

Installation Guidelines

The i3 Series detectors represent an advancement over the previous
sounder and Form C relay models and are designed to be used with the
2W-MOD2 and RRS-MOD only. Do not mix detector models on a zone.

D100-99-00 2 I56-2170-04R

NOTE: FOR ALL COMPATIBLE ADEMCO PANELS,

DO NOT EXCEED 30 OHMS LINE IMPEDANCE.

NOTE: ONLY ONE 2WTR-B DETECTOR PER ZONE CAN BE USED.

S0122-00

NOTE: Only one 2WTA-B detector shall be installed on a zone,

AUX OR
SMOKE
POWER

IDC

4-WIRE
CONTROL
PANEL

+

+

–

–

(

5
)

A

(

4
)

A

(

3
)

– IN/OUT

(

2
)

+ OUT

(

1
)

+ IN

EOL
RELAY
(

A77-716B

)

EOL
RESISTOR

(

5
)

A

(

4
)

A

(

3
)

– IN/OUT

(

2
)

+ OUT

(

1
)

+ IN

NOT INCLUDED ON
4WTA-B MODEL

NOT INCLUDED ON
4WTA-B MODEL

OPTIONAL
RELEASING
DEVICE

(6) NC

(7) C

(8) NO

OPTIONAL
RELEASING
DEVICE

(6) NC

(7) C

(8) NO

WARNING

CAUTION

LED

RECESSED TEST SWITC

H

POSITION SENS-RDR
AT

AN ANGLE ON THE
OVAL AREA OR AT THE
CHAMBER OPENIN

G

BY

THE WORD “PAINT”

PUSH RECESSED
SWITCH WITH
A

0.18″ MAX.

DIAMETER

TOOL

WARNING

unless the panel switches the zone to a reverse polarity, non-cur­rent limited power supply. For panels that do not provide this fea­ture, a reversing relay, System Sensor model RRS-MOD, may be
used. When utilized with the 2WTA-B, it allows for more than one
detector to be utilized on a loop. Some panels may require the use
of programmable outputs. Refer to System Sensor literature for
further information on the RRS-MOD. The 2WTA-B detector shall
not be mixed with other 2-wire detectors on the same zone.

Figure 3b: Wiring Diagram, 4WTR-B, 4WTA-B, 4WTAR-B, and
4WITAR-B

prevent any unwanted alarms.

Ensure proper wiring and power is applied. After power up, allow

80 seconds for the detector to stabilize before testing.

Test i3 Series detectors as follows:
A. Test Switch

1. An opening for the recessed test switch is located on the
detector housing (See Figure 4).

2. Insert a small screwdriver or allen wrench (0.18″ max.) into
the test switch opening; push and hold.

3. If the detector is within the listed sensitivity limits, the
detector’s red LED should light within one second.

Figure 4: Recessed Test Switch Opening and SENS-RDR
Position

B. Smoke Entry Test

S0110-00

Hold a smoldering punk stick or cotton wick at the side of the

S0123-00

Installation

detector and gently blow the smoke through the detector until

it alarms.
C. Direct Heat Method
Using a 1000-1500 watt hair dryer, direct the heat toward either

Remove power from alarm control unit or initiating device circuits
before installing detectors.

NOTE: To install units so that corresponding LEDs are lined up,
refer to the “Green LED” indicator on the base.

1. Wire the mounting base screw terminals per Figure 3a or
Figure 3b, as applicable.

2. Place detector on the base and rotate clockwise. The detector
will drop into the base and lock into place with a “click”.

3. After all detectors have been installed, apply power to the
alarm control unit.

4. Test each detector as described in Testing.

5. Reset all the detectors at the alarm control unit.

6. Notify the proper authorities that the system is in operation.

of the thermistors. Hold the heat source about 12 inches from
the detector to avoid damage to the plastic.

NOTE: For the above tests, the detector will reset only after the power
source has been momentarily interrupted. It is not necessary to reset
the model 4WITAR-B, when smoke is used to initiate the alarm.

When testing the 4WITAR-B model, pressing the test switch will
result in a non-latching local alarm that does not alarm at the con­trol panel. Once the test button is released, the unit will return to its
standby condition. Only the fixed-temperature heat sensor will cause
the 4WITAR-B to initiate an alarm at the panel.

If a detector fails any of the above test methods, its wiring should be
checked and it should be cleaned as outlined in the Maintenance
section. If the detector still fails, it should be replaced.

Notify the proper authorities when the system is back in service.

Dust covers are an effective way to limit the entry of dust into
the smoke detector sensing chamber during construction.
However, they may not completely prevent airborne dust particles
from entering the detector. Therefore, System Sensor recommends
the removal of detectors before beginning construction or other
dust producing activity. When returning the system to service, be
sure to remove the dust covers from any detectors that were left
in place during construction.

Testing

Detectors must be tested after installation and following
maintenance.

NOTE: Before testing, notify the proper authorities that mainte­nance is being performed and the system will be temporarily out
of service. Disable the zone or system undergoing maintenance to

D100-99-00 3 I56-2170-04R

Loop Verification (models 2WTR-B and 2WTA-B only)

Loop verification is provided by the EZ Walk loop test feature.
This feature is for use with i3 Series compatible control panels or
the i3 Series 2W-MOD2 module only. The EZ Walk loop test veri­fies the initiating loop wiring and provides visual status indica­tion at each detector. Refer to System Sensor literature for further
information on the 2W-MOD2.

The 2W-MOD2 has replaced the previous model number 2W­MOD. To ensure proper EZ Walk Test capabilities, do not use the
2W-MOD with i3 model numbers 2WTR-B and 2WTA-B.

Table 3: EZ Walk Test Detector Modes

REMOVABLE
DETECTOR
COVER

SCREEN/SENSING
CHAMBER
(TOP HALF)

DETECTOR
HOUSING

|Green LED |Red LED
Proper Operation |Double blink 5 sec |—
Out of Sensitivity |— |Double Blink 5 sec
Freeze Condition |— |Double Blink 10 sec

NOTE: The EZ Walk loop test must not be used instead of alarm

testing.

Maintenance

NOTE: Before performing maintenance on the detector, notify
the proper authorities that maintenance is being performed and
the system will be temporarily out of service. Disable the zone or
system undergoing maintenance to prevent any unwanted alarms.

Power must be removed from the detector before performing
maintenance of any kind.

1. Remove the detector cover by turning counterclockwise. (See
Figure 5.)

2. Vacuum the cover or use canned air to remove any dust or
debris.

3. Remove the top half of the screen/sensing chamber by lifting
straight up (Figure 5).

4. Vacuum or use canned air to remove any dust or particles that
are present on both chamber halves.

5. Replace the top half of the screen/sensing chamber by aligning
the arrow on the screen/sensing chamber with the arrow on the
housing. Press down firmly until the screen/sensing chamber is
fully seated.

6. Replace the detector cover by placing it over the screen/sensing
chamber and turning it clockwise until it snaps into place.

7. Reinstall the detector and test. (See the Testing section.)

8. Notify the proper authorities when the system is back in service.

Figure 5: Removing Screen/Sensing Chamber

S0111-00

Electrical Specifications 2-wire 4-wire

System Voltage –Nominal: 12/24 12/24 V (Non-polarized for
2WTR-B and 4WTR-B)
Min.: 8.5 10 V
Max.: 35 35 V
Max. Ripple Voltage: 30 30 % peak to peak
of applied voltage
Avg. Standby Current: 50 50 µA average
Peak Standby Current: 100 — µA
Max. Alarm Current
4WTA-B, 4WTR-B: — 35 mA
4WTAR-B, 4WITAR-B: — 50 mA
2WTR-B: 130 — mA panel must limit
current
2WTA-B: 130*
Alarm Contact Ratings: — 0.5 A @ 30 V AC/DC
Form C Contact Ratings: 2 2 A @ 30 V AC/DC
Audible Signal
(temp-3 tone): 85 85 dBA min. in alarm or
supply polarity
reversed (Sounder
units only)
Remote Annunciator Output: 7 — mA maximum
EOL Relay: — 12/24 A77-716B
Reset Time (min): 0.3 0.3 seconds
Max. Start-up Capacitance: 0.1 — µF
Max. Initial Start-up Time: 45 15 seconds
Alarm Verification**
Start-up Time: 15 15 seconds

* Direct Power (Non-reverse Polarity): 130 mA limited by panel.

Reverse Polarity Power: 30 mA for the 2WTA-B in alarm; 12 mA for all other 2WTA-B
units on the loop. Add 25 mA for the RRS-MOD reversing relay alarm current.

** Assumes the panel’s alarm verification reset time is 10 seconds or less. Should the

alarm verification reset exceed 10 seconds, use the maximum initial start-up time.

Physical Specifications

Heat Sensor: 135°F (57.2°C)
Freeze Trouble: 41°F (5°C)
Operating Temperature Range: 32 to 100°F (0 to 37.8°C)
Operating Humidity Range: 0 to 95% RH non-condensing
Storage Temperature Range: –4 to 158°F (–20 to 70°C)
Diameter (including base): 5.3 inches
Height (including base): 2.0 inches
Weight: 7.1 oz.

Please refer to insert for the Limitations of Fire Alarm Systems

Three-Year Limited Warranty

System Sensor warrants its enclosed smoke detector to be free from defects in
materials and workmanship under normal use and service for a period of three
years from date of manufacture. System Sensor makes no other express war­ranty for this smoke detector. No agent, representative, dealer, or employee of
the Company has the authority to increase or alter the obligations or limitations
of this Warranty. The Company’s obligation of this Warranty shall be limited to
the replacement of any part of the smoke detector which is found to be defective
in materials or workmanship under normal use and service during the three year
period commencing with the date of manufacture. After phoning System Sensor’s
toll free number 800-SENSOR2 (736-7672) for a Return Authorization number,
send defective units postage prepaid to: System Sensor, Returns Department, RA

This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference, and (2) this
device must accept any interference received, including interference that may cause undesired operation.

Note: This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to

provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses and can radiate radio frequency energy and, if
not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference
will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the

equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:
– Reorient or relocate the receiving antenna.
– Increase the separation between the equipment and receiver.
– Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
– Consult the dealer or an experienced radio/TV technician for help.

FCC Statement

D100-99-00 4 I56-2170-04R
©System Sensor 2003

#__________, 3825 Ohio Avenue, St. Charles, IL 60174. Please include a note
describing the malfunction and suspected cause of failure. The Company shall not
be obligated to repair or replace units which are found to be defective because of
damage, unreasonable use, modifications, or alterations occurring after the date
of manufacture. In no case shall the Company be liable for any consequential or
incidental damages for breach of this or any other Warranty, expressed or implied
whatsoever, even if the loss or damage is caused by the Company’s negligence or
fault. Some states do not allow the exclusion or limitation of incidental or con­sequential damages, so the above limitation or exclusion may not apply to you.
This Warranty gives you specific legal rights, and you may also have other rights
which vary from state to state.