System Sensor B401B User Manual

D450-01-01 1 I56-298-09R

B401B Plug-in Detector Base

INSTALLATION AND MAINTENANCE INSTRUCTIONS

3825 Ohio Avenue

St. Charles, Illinois 60174

1-800-SENSOR2, FAX: [phone]

Before Installing

Please thoroughly read the System Sensor manual I56-407,
Guide for Proper Use of System Smoke Detectors, which pro­vides detailed information on detector spacing, placement,
zoning, wiring, and special applications. Copies of this man­ual are available at no charge from System Sensor. (For instal­lations in Canada, refer to CAN4-S524, Standard for the
Installation of Fire Alarm Systems, and CEC Part 1, Sec. 32.)

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

IMPORTANT: The detector used with this base must be
tested and maintained regularly following NFPA 72 require­ments. The detector used with this base should be cleaned
at least once a year.

Specifications

Base Diameter: 6.2 inches (15.7 cm)
Base Height: 1.1 inches (2.8 cm)
Weight: 0.3 lb. (130 g)
Mounting: 4-inch square box with or without plaster ring. Min. Depth–1.5 inches

4-inch octagon box. Min. Depth–1.5 inches

31⁄2 inch octagon box. Min. Depth–1.5 inches
Operating Temperature Range: 0° to +49°C (32° to 120°F)
Operating Humidity Range: 10% to 93% Relative Humidity, noncondensing
Electrical Ratings — includes base and detector
System Voltage: 12/24 VDC
Maximum Ripple Voltage: 4 Volts peak to peak
Start-up Capacitance: 0.02 µF Maximum
Standby Ratings: 8.5 VDC Minimum; 35 VDC Maximum

120 µA Maximum
Alarm Ratings: 4.2 VDC Minimum at 10 mA; 6.6 VDC Maximum at 100 mA

(Alarm current must be limited to 100 mA by the control panel. If used, the RA400

remote lamp operates within specified detector alarm currents.)
Reset Voltage: 2.5 VDC Minimum
Reset Time: 0.3 Seconds Maximum
Start-up Time: 34.0 Seconds Maximum

For use with the following smoke detectors:
1451, 2451, and 2451TH

General Description

The B401B plug-in detector base is used with System
Sensor model 2451 and 2451TH photoelectronic detector
heads and model 1451A ionization detector heads. The
capability of plugging these detectors into a variety of spe­cial bases makes them more versatile than equivalent
direct-wired models. Refer to the System Sensor catalog for
other available plug-in detector bases.

This base is intended for use in 2-wire systems, with screw
terminals provided for power, ground, and remote annun­ciator connections.

D450-01-01 2 I56-298-09R

Mounting

This detector base mounts directly to 31⁄2-inch and 4-inch
octagon boxes, and 4-inch square boxes (with or without
plaster rings). To mount, remove the decorative ring by
turning it in either direction to unhook the snaps, then sep­arate the ring from the base.

Install the base to the box using the screws supplied with
the junction box and the appropriate mounting slots in the
base (see Figure 1). Place decorative ring onto base, then
turn in either direction until the ring snaps in place.

Installation Guidelines

All wiring must be installed in compliance with the
National Electrical Code and the local codes having juris­diction. Proper wire gauges should be used. The conduc­tors used to connect smoke detectors to control panels 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.

For signal wiring (the wiring between interconnected
detectors), it is recommended that the wire be no smaller
than 18 gauge (1.0 square mm). Wire sizes up to 12 gauge
wire (2.5 square mm) may be used with the base. For best
system performance, the power (+) and (–) loop wires
should be twisted pair and installed in separate grounded
conduit to protect the loop from extraneous electrical inter­ference.

Smoke detectors and alarm system control panels have
specifications for allowable loop resistance. Consult the
control panel manufacturer’s specifications for the total

loop resistance allowed for the particular model control
panel being used before wiring the detector loops.

Locate installations where the normal ambient tempera­tures do not exceed 100° F.

2

3

4

1

REMOTE

ANNUNCIATOR

2

3

4

1

REMOTE

ANNUNCIATOR

2-WIRE CONTROL PANEL

E
O
L

CLASS A OPTIONAL WIRING

Figure 2. Typical wiring diagram for 2-wire detector systems:

A78-1175-04

Figure 1. Mounting base to box:

A78-1175-01

SHORTING
SPRING

SNAP ON
DECORATIVE
RING

SCREWS (NOT
SUPPLIED)

DETECTOR
BASE

BOX (NOT
SUPPLIED)

D450-01-01 3 I56-298-09R

Wiring Instructions

For system supervision — For terminals 2, 3, and 4 do not
use looped wire under terminals. Break wire run to provide
system supervision of connections.

Wire connections are made by simply stripping insulation
from the end of the wire, sliding the bare end of the wire
under the clamping plate, and tightening the clamping
plate screw. Use the strip gauge molded into the base for
ease of wiring to terminals 1 through 4.

System Sensor smoke detectors and mounting bases are
marked with a compatibility identifier located as the last
digit of a five digit code stamped on the back of the prod­uct. Connect detectors/mounting bases only to compatible
control units as indicated in System Sensor’s compatibility
chart which contains a current list of UL listed control units
and detector head/base combinations. A copy of this list is
available from System Sensor upon request.

The zone wiring of the detector base should be checked
before the detector heads are installed in them. To make
this possible, this base contains a special spring-type short­ing jumper. After a detector base is properly wired and
mounted on an electrical box, make sure that the jumper
spring is in contact with the base of Terminal 3. This tem­porary connection shorts the negative-in and negative-out
leads and permits the wiring of the loop to be checked for
continuity.

Once all the detector bases have been wired and mounted,
and the loop wiring has been checked, the detector heads
may be installed in the bases. The shorting spring in the
base will disengage automatically when the detector head
is removed from the base. DO NOT remove the shorting
spring since it reengages as the detector head is turned into
the base, completing the circuit.

CAUTION

Tamper-resistance Feature

Do not use the tamper-resistance feature if the XR2 removal
tool is to be used.

The tamper-resistant tab, in the detector mounting bracket,
can make the detector tamper-resistant by making it neces­sary to use a small screwdriver or similar tool to detach the
detector from the bracket.

To make the detector tamper-resistant, use needle-nose pli­ers to break the smaller tab at the scribed line on the tamp­er-resistance tab. Figure 3A shows the location of this tab
on the detector mounting bracket. To remove a detector
from the bracket after it has been made tamper resistant,
use a small screwdriver or other similar tool, to depress the
tamper-resistance tab in the slot on the mounting bracket,
and rotate the detector counterclockwise (see Figure 3B).

NOTE: The decorative ring must be removed before the

smoke detector can be detached from the base
after the tamper-resistant capability is enabled.

The tamper-resistance feature can be defeated by breaking
and removing the plastic lever from the base. However, this
prevents ever using the feature again.

CAUTION

Figure 3A. Activating the tamper-resistance feature:

A78-1175-03

Figure 3B. Removing detector head from the base:

PLASTIC LEVER

BREAK TAB AT
DOTTED LINE BY
TWISTING TOWARD
CENTER OF BASE.

USE SMALL-BLADED
SCREWDRIVER TO
PUSH PLASTIC LEVER
IN DIRECTION OF
ARROW.

D450-01-01 4 I56-298-09R

©2001 System Sensor

Three-Year Limited Warranty

System Sensor warrants its enclosed smoke detector base 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 base. 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 repair or replacement of
any part of the smoke detector base 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, Repair Department, RA #__________, 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.

Please refer to insert for the Limitations of Fire Alarm Systems