Simplex TrueAlarm Sensor Bases 4098-9775, 4098-9780, and 4098-9789

The Simplex TrueAlarm Sensor Bases 4098-9775, 4098-9780, and 4098-9789 are designed to support compatible TrueAlarm smoke, heat, and multi-sensors in addressable fire alarm systems.

These sensor bases provide the physical mounting point, electrical connection, and communication interface between the installed sensor and the compatible Simplex fire alarm control panel. Selected models also support remote LED indicators, supervised relays, or unsupervised relay accessories.

For fire alarm contractors, system integrators, engineers, and facility managers, selecting the correct TrueAlarm sensor base is important for achieving proper sensor operation, alarm indication, relay control, and system compatibility.

What Are Simplex TrueAlarm Sensor Bases?

A TrueAlarm sensor base is the mounting and electrical connection component used with compatible Simplex addressable sensors.

The sensor head attaches to the base, while the base connects to the building’s fire alarm wiring. Depending on the selected model, the base may provide:

• IDNet or MAPNET II communication

• Sensor supervisory power

• Remote LED alarm indication

• Unsupervised relay output

• Supervised relay control

• Two-wire or four-wire relay operation

Each installed base generally uses one address when connected to a compatible Simplex addressable communication circuit.

Simplex 4098-9775 Sensor Base

The 4098-9775 is a black TrueAlarm sensor base designed with connections for a remote LED alarm indicator or an unsupervised relay.

This model is functionally related to the white 4098-9789 base but is supplied in a black housing for installations where a dark-colored device finish is preferred.

Key Features of the 4098-9775

• Black sensor-base housing

• Compatible with selected TrueAlarm sensors

• Connections for a remote LED alarm indicator

• Supports the 4098-9822 unsupervised relay

• Addressable communication through a compatible Simplex system

• Suitable for selected architectural or dark-ceiling applications

The base may be used with the 2098-9808 remote alarm indicator or the 4098-9822 unsupervised relay, subject to system design and compatibility.

Simplex 4098-9789 Sensor Base

The 4098-9789 is a white TrueAlarm sensor base with wired connections for a remote LED alarm indicator or an unsupervised relay.

It is commonly selected for standard indoor installations where remote alarm indication or a basic relay output is required.

Key Features of the 4098-9789

• White sensor-base housing

• Connections for remote LED indication

• Supports an optional unsupervised relay

• Compatible with selected TrueAlarm smoke, heat, and multi-sensors

• Uses compatible IDNet or MAPNET II communications

• Suitable for standard ceiling and wall installations

The 4098-9789 may be paired with the 2098-9808 remote red LED alarm indicator. It may also support the 4098-9822 unsupervised relay, which tracks the LED status of the base and requires a separate 24 VDC supply.

Simplex 4098-9780 Supervised Relay Base

The 4098-9780 is a white two-wire supervised relay sensor base designed for applications requiring a controllable relay function.

Unlike a basic sensor base, the 4098-9780 can operate with the compatible 4098-9860 supervised relay. The relay may be mounted locally in the base electrical box or remotely, depending on the installation requirements.

Key Features of the 4098-9780

• White two-wire supervised relay base

• Supports the 4098-9860 supervised relay

• Relay power is supplied through the communication circuit

• Connections for a remote LED alarm indicator

• Supports an optional unsupervised relay

• Relay operation can be programmed through the compatible control panel

• Suitable for addressable fire alarm control applications

The 4098-9780 does not require a separate relay power supply for the compatible supervised relay because its relay power is supplied through communications. It is not compatible with the older 2120 CDT system.

Benefits of Using Simplex TrueAlarm Sensor Bases

Secure Sensor Mounting

The base provides a stable connection point for the compatible TrueAlarm sensor head.

This allows the sensor to be removed for testing, cleaning, or replacement while the permanent wiring remains connected to the installed base.

Addressable System Communication

Compatible bases allow the installed sensor to communicate with a Simplex fire alarm control panel through IDNet or MAPNET II addressable communications.

This helps the system identify the exact sensor location and monitor alarm, trouble, and maintenance conditions.

Remote Alarm Indication

The 4098-9775, 4098-9789, and 4098-9780 can support a remote LED alarm indicator when the sensor is installed in a concealed or difficult-to-view location.

Remote LED indicators may be useful for detectors installed:

• Above suspended ceilings

• Inside enclosed rooms

• In ceiling voids

• In concealed mechanical spaces

• In areas where the sensor LED is not easily visible

Relay Control Options

Relay accessories can provide an interface between the fire alarm system and other equipment.

Depending on the approved system programming, relay functions may be used for:

• Door release

• HVAC shutdown

• Local alarm indication

• Equipment shutdown

• Damper control

• Auxiliary notification

• Building-management system input

Relay use must follow the approved cause-and-effect sequence and project specifications.

Easier Maintenance

Because the addressable sensor head attaches to a separate base, technicians can remove and replace the sensor without disturbing the permanent circuit wiring.

This can reduce maintenance time and help protect the integrity of the installed wiring.

The 4098-9775 and 4098-9789 provide similar remote-output functionality, with the primary visible difference being the housing color. The 4098-9780 is intended for applications requiring a supervised relay function.

Typical Applications of TrueAlarm Sensor Bases

The 4098-9775, 4098-9780, and 4098-9789 sensor bases may be used in compatible fire alarm systems for:

• Commercial office buildings

• Condominium and apartment buildings

• Hotels and resorts

• Hospitals and healthcare facilities

• Schools and universities

• Shopping centers

• Warehouses

• Manufacturing facilities

• Data centers

• Government buildings

• Fire alarm upgrade projects

• Mechanical and electrical rooms

• Concealed detector installations

• Auxiliary equipment control applications

The final base selection should match the required sensor, system communication type, relay function, housing color, electrical box, and approved fire alarm design.

Compatible Sensors

These bases are listed for use with selected Simplex TrueAlarm sensors, including compatible:

• Photoelectric smoke sensors

• Heat sensors

• High-temperature heat sensors

• Photoelectric and heat multi-sensors

Examples identified in Simplex documentation include the 4098-9714 photoelectric sensor, 4098-9774 black photoelectric sensor, 4098-9733 heat sensor, 4098-9778 black heat sensor, and selected TrueSense multi-sensors. Exact compatibility must be verified using the latest data sheet for the sensor and control panel.

Installation Considerations

A TrueAlarm sensor base should be installed only by qualified fire alarm personnel.

Before installation, confirm:

• Exact base model

• Required housing color

• Compatible sensor head

• Fire alarm control panel model

• IDNet or MAPNET II compatibility

• Required relay function

• Remote LED requirement

• Electrical-box size and depth

• Wire size and quantity

• System address

• Approved mounting location

• Fire alarm drawings and specifications

Mounting Requirements

Depending on the selected base and accessory, mounting may require:

• 4-inch octagonal electrical box

• 4-inch square electrical box

• Single-gang electrical box

• Adapter plate

• Extension ring

• Sufficient box depth for wire count and accessories

The 4098-9832 adapter plate may be required for selected surface-mounted or semi-flush electrical-box arrangements.

Verify Wiring Connections

TrueAlarm bases use screw terminals for addressable communication wiring. Remote LED and relay options may use color-coded wire leads.

Incorrect wiring may cause:

• Missing-device trouble

• Communication failure

• Relay malfunction

• Incorrect alarm indication

• Ground faults

• System supervisory trouble

All connections should follow the manufacturer’s installation instructions.

Confirm Sensor and Base Color

The 4098-9775 is black, while the 4098-9789 and 4098-9780 are white.

Color selection may be important for architectural ceilings, dark-painted areas, theaters, hotels, retail interiors, and other visible installations.

Testing and Commissioning

After installation, the sensor base and connected device should be tested as part of the complete fire alarm system.

Testing should confirm:

• The panel recognizes the correct sensor

• The assigned device address is accurate

• The programmed location description is correct

• The sensor enters alarm properly

• The remote LED operates when installed

• The relay activates according to programming

• Controlled equipment responds correctly

• Trouble conditions are supervised

• The system resets and returns to normal

Relay testing should include verification of the full cause-and-effect sequence rather than only checking the relay contacts.

Maintenance and Inspection

The sensor head should also be tested and maintained according to the applicable manufacturer instructions and fire alarm maintenance program.

Common Installation Mistakes to Avoid

Avoid the following issues:

• Ordering the wrong base color

• Using an incompatible sensor

• Installing the wrong relay accessory

• Confusing an unsupervised relay with a supervised relay

• Using the 4098-9780 with an incompatible legacy system

• Installing an undersized electrical box

• Failing to provide the required adapter plate

• Incorrectly wiring the remote LED

• Failing to program relay operation

• Using the relay beyond its approved contact rating

• Assigning the wrong device location

• Failing to test controlled equipment

• Painting or modifying the base

• Installing the sensor before construction dust has cleared

Important Considerations Before Selecting a Sensor Base

Before purchasing a 4098-9775, 4098-9780, or 4098-9789 sensor base, confirm:

• Exact base model

• White or black housing requirement

• Compatible TrueAlarm sensor model

• Existing fire alarm control panel

• Communication protocol

• Required relay type

• Remote LED requirement

• Relay contact load

• Electrical-box dimensions

• Required mounting accessories

• Project approvals and listings

• Fire alarm programming requirements

• Replacement compatibility

Do not select the base based only on appearance. The relay and accessory capabilities vary by model.

Source Simplex TrueAlarm Sensor Bases from Pinoleakpes Enterprises Corporation

Pinoleakpes Enterprises Corporation supplies quality fire detection, fire protection, mechanical, and industrial system products, including Simplex TrueAlarm smoke sensors, heat sensors, sensor bases, relay bases, remote indicators, manual pull stations, modules, and fire alarm accessories.

Our team can assist you in selecting the appropriate 4098-9775, 4098-9780, or 4098-9789 TrueAlarm Sensor Base based on your sensor model, panel compatibility, relay requirement, housing color, project specification, and installation application.

Contact Pinoleakpes Enterprises Corporation today for product availability, technical assistance, and quotation requirements.