System Sensor 2WTR-B, 2WTA-B, 4WTR-B, 4WTAR-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 Applications Guide for System
Smoke Detectors, which provides detailed information on detector spac-

ing, 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 RRS­MOD 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
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 2W-MOD2
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 2W-MOD. To en­sure proper remote maintenance signaling capabilities, do not use the 2W­MOD with i3 model numbers 2WTR-B and 2WTA-B.

D100-99-00 1 I56-2170-007R

Installation of the 2WTR-B, 2WTA-B, 4WTR-B, 4WTA-B, 4WTAR-B, 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 detec
tor’s status:

Table 1: Detector LED Modes

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 syn
chronously 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

Initial LED Status Indication
(if excessive electrical noise is present)

* Refer to Electrical Specifications for start-up time in conjunction 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).

After power-up has completed and the detector is functioning 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 SENS-RDR 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.

3825 Ohio Avenue, St. Charles, Illinois 60174

1-800-SENSOR2, FAX: [phone]

www.systemsensor.com

Green LED Red LED

80 seconds

4 minutes

-

-

Figure 1: Mounting of Detector

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

CAUTION

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

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 4WTR­B, 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 4­wire. 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.

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.

Figure 2: Tamper-Resistant Feature

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

S0122-00

NOTE: FOR ALL COMPATIBLE ADEMCO PANELS,

DO NOT EXCEED 30 OHMS LINE IMPEDANCE.

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

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

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 color­coded 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 insula-

tion 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 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.

D100-99-00 2 I56-2170-007R

S0109-00

Any 2-wire i3 smoke detector (2W-B, 2WT-B, 2WTA-B, or 2WTR-B) wired
in the Style D initiating device circuit (IDC) configuration requires the use
of a 2W-MOD2 module. This is because fire alarm control panels vary by
manufacturer on the implementation of Style D circuits. Therefore, the
only way to insure proper operation of 2-wire i3 smoke detectors (2W-B,
2WT-B, 2WTA-B, or 2WTR-B) on Style D IDC’s is to use a 2W-MOD2 mod­ule. Refer to the 2W-MOD2 installation manual, document D500-46-00,
for Style D wiring diagrams. The 2W-MOD2 installation manual may be
downloaded from the System Sensor web site at www.systemsensor.com.

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

S0123-00

Installation

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.