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