In May 2004, Underwriters Laboratories (UL) revised UL 1971, regulating how operating currents are to be measured and how voltage ranges are to be listed and published.

Historically, fire-alarm system designers used 24-volt current draw for computing voltage drops on audible and visible (AV) circuits. However, voltage drops based on 24-volt current draw only provide an illusion of lower current draw, placing the reliability of the circuit in question.

UL recognized confusion within the industry because AV appliance circuit calculations were being performed with the wrong current draw. They saw the potential for circuit failures.

UL Max to Denote Current Ratings

Seldom is the voltage at AV devices exactly 24 volts. This is due to the natural voltage drop in the circuit. Depending where the device is located on the circuit, the voltage could drop to its lowest operating voltage.

This means that because device currents vary with applied voltage, the only way to assure the power supply will provide enough current to the entire circuit is to measure current for each device at its highest value.

Based on this logic, UL now requires that current-rating published in installation manuals are to symbolize the maximum current draw (UL Max) over the listed voltage range. These true current ratings will:

1. Reflect device power usage more accurately.
2. Ensure compatibility between devices and outputs on the control panel, regardless of manufacturer.
3. Present comparable current-draw data amongst manufacturers.

Incorrect Data is Still Printed Today

Despite UL’s efforts, some manufacturers are still printing 24-volt current draws on their data sheets. Current draws based on 24 volts can confuse industry professionals who don’t realize that these specifications shouldn’t be used for circuit calculations.

To eliminate confusion throughout the industry, System Sensor is advertising a white paper that gives details and examples of the UL 1971 revision.

You can download a free copy of the white paper, and you can sign up for one of System Sensor’s Fire Protection seminars to learn about the latest fire-detection technologies and UL requirements, by visiting System Sensor’s website atwww.systemsensor.com.

The revised Americans with Disabilities Act Accessibility Guidelines (ADAAG), which harmonize the ADA guidelines with the National Fire Protection Association (NFPA) and American National Standards Institute (ANSI),were completed last year. The Access Board, an independent federal agency devoted to accessibility for people with disabilities, coordinated extensively with these model code groups and standard-setting bodies so that differences could be reconciled. Through this update, the Board sought to make its guidelines more consistent with model building codes and industry standards in order to make compliance easier.

The guidelines have not taken effect yet and are not mandatory for the public, but instead serve as the baseline for enforceable standards. Essentially, the Access Board only writes the ADAAG as a “standard,” which then has to be adopted by the affected governmental bodies. In this respect, they are similar to a model building code in that they are not required to be followed except as adopted by an enforcing authority.

Under the ADA, the Department of Justice and, in the case of transit facilities, the Department of Transportation, are responsible for enforceable standards based on the Board’s guidelines. These agencies will update their accessibility standards based on the new guidelines. In doing so, they will indicate when the new standards are to be followed.

The final revised guidelines are not enforceable and will not have any impact until they are adopted as enforceable standards by the following agencies:

• Department of Justice: State and local government facilities, places of public accommodation and commercial facilities
• Department of Transportation: Public transportation facilities owned or operated by state and local governments and the National Railroad Passenger Corporation
• Department of Housing and Urban Development: Federally financed residential facilities
• Department of Defense: Military facilities
• United States Postal Service: Postal facilities
• General Services Administration: All other federally financed facilities

The Department of Justice, Department of Transportation, Department of Housing and Urban Development and General Services Administration will publish a notice in the federal register regarding a comment period on whether to adopt the final revised guidelines as enforceable standards.

All of these departments are on separate timeframes for adoption. This will likely result in even more confusion as some groups apply the standards of the old ADAAG while some have already adopted the new set, including the USPS, which has identified Oct. 1, 2005, as the active date. In contrast, the Department of Justice is particularly slow, and the Access Board tech support hot line has suggested that it might be two years away from adoption. The following steps need to take place:

• Analyze public comments from comment period that ended May 31, 2005.
• Reissue the “proposed rule” incorporating the public comments.
• Hold another public comment period, including public hearings around the country.
• Analyze public comments.
• Finalize the new ADAAG as an enforceable standard with effective dates.

What Changes Lie Ahead or Fire Safety?

Chapter 7: “Communication Elements and Features” expands on the fire and life-safety system changes that will affect building professionals based on adoption of the proposed ADAAG.

This chapter provides technical criteria for communication elements, such as fire alarms (702), signs (703), telephones (704), detectable warnings (705), assistive listening systems (706), ATMs and fare machines (707) and two-way communication systems (708).

Substantive changes include: addressing technical criteria for fire alarms through the National Fire Alarm Code (NFPA 72), which effectively overhauls specifications for visual alarms in a manner that will facilitate compliance while enhancing design and installation options.

The new ADAAG goes a long way toward reconciling the differences between it and NFPA 72 that have resulted in confusion over the past several years. Once it is fully adopted, the guideline will make compliance for notification appliances much easier.

More and more cities have introduced bylaws, ordinances or policies designed to recover the costs of responding to false alarms. There are municipal code sections that describe the alarm permit requirements, fees, exceptions, and penalties for excessive false alarm responses. Although each city has different codes, the proprietor of the alarm system pays a fee for each false alarm responded to by the police and/or fire department.

One example is the city council in Eureka, California, which has increased its fines for excessive false alarms by as much as 400 percent. Unlike fines in other municipalities, the penalties in Eureka will apply to the number of false alarms within a six-month period, instead of within a year. The fee structure is: For a third false alarm within a six-month period the fine goes up from $25 to $50, while the fine for a fourth false alarm goes up from $50 to $200.

What to do About Unwanted Alarms

Fire-protection design doesn’t need to be an expensive guessing game. The National Fire Protection Association (NFPA) — and all the building codes — continue to stress active fire protection in the form of sprinklers and alarm and detection systems. Fire alarm systems have a proven record, and active smoke control and sprinkler systems can extend the available egress time, minimize smoke, and actively suppress or extinguish a fire. With more challenging designs, it becomes critical to properly install and maintain the fire protection systems.

While no detection system is impervious to unwanted alarms, the best way to avoid unwanted alarms is to install detectors specially designed for those environments.

Unwanted alarms can result from a wide variety of causes:

• Improper locations are environments where detectors will not operate properly because of temperature extremes; excessive dust, dirt, or humidity, excessive airflow rates, or the normal presence of combustion particles in the air streams surrounding the detectors.
• Improper installation can occur when detectors and their wiring are not protected from interference from induced currents and noise in adjacent wiring systems, radio frequency transmissions, and other types of electromagnetic effects.
• Inadequate maintenance can result in the accumulation of dust and dirt on the detector’s sensing chambers over a period of time.
• Seasonal effects such as the reactivation of a building heating system after an extended summer shutdown can cause alarms.
• Building maintenance issues, such as accidental triggering of a detector’s magnetic test switch, or the introduction of plaster dust from drywall repairs into a detector’s sensing chamber can cause unwanted alarms.
• Induced current effects from lightning storms.
• Infestation from insects small enough to enter the detector’s sensing chamber.
• Vandalism or mischievous acts: detectors set off as a prank have been found to be a problem in dormitories.

Maintenance Practices

Make sure that all the detectors in the zone or pinpointed devices that show an alarm are checked before deciding that it is a false alarm. If a fire does exist, more than one detector may be in the alarm state, although no signs of fire may be evident in the vicinity of the first activated detector. The fire could be overlooked.

Isolated alarm incidents, such as a maintenance person accidentally triggering an alarm by touching a detector with a magnetic screwdriver, can be ignored except to periodically remind maintenance personnel to be careful when working around detectors. Steps should also be taken to protect detectors from dust whenever maintenance requires sawing, sanding, drilling, or other dust-producing operations in the vicinity of the detector heads to prevent false alarms.

In new construction applications, drywall dust contamination affects all types of smoke detectors. To help overcome this problem or to protect detector heads from dust contamination, installation of detector heads should be delayed until after drywall installation is completed.

If alarms occur whenever the heating system is turned on after an extended shutdown due to the accumulated dust burning off as the system components heat, the detector system can be turned off for a short period while the heating system is activated and checked out. Or the start-up of the heating system can be scheduled for an evening, weekend or other off-peak period to minimize the effects of alarms on regular daytime activities.

Dirt, interference or other effects on the detectors do not cause all unwanted alarms. If the control panel shows an alarm but no detectors in the zone are indicating an alarm condition, the possibility of interference or a failure of a control panel component should also be investigated.

In the event of a series of unexplained, unwanted alarms, a review of the Alarm Log can indicate that a problem situation exists, and the owner should conduct the initial investigation to find a solution. If the owner’s personnel are unable to determine the cause for the alarms, the installer or representative of the manufacturer should be contacted to help pinpoint the problem.

Detectors should be given a visual inspection at installation and at least once a month thereafter. This ensures that each detector remains in good physical condition and that there are no changes that would affect detector performance, such as building modifications, occupancy hazards, and environmental factors.

Q. How are today’s fire and life safety systems different from those of 10 years ago?

Mulkerrin: The most significant changes are computer logic, building automation and tel-data for advanced communication systems. Most equipment now is linked to an Ethernet or a phone line and all communication is streamlined to go to a person of responsibility who can be reached 24/7.


Anderson: The result is improved safety; response times are much shorter to minimize fire damage; and someone who is responsible knows what’s going on with the building any time there is a problem. The systems today notify authorities, building managers or anyone on the list who needs to know about a trouble scenario.

Q. What happens when there is a trouble scenario?

Anderson: If there’s a trouble signal, the building manager can just dial in on a computer to see what’s going on. But if there is an alarm, the manager is alerted to get to the site and the message is sent to the fire and police departments immediately.

Mulkerrin: Trouble can result from shutting off a supervised valve for maintenance or if a smoke detector is not functioning properly. If a supervised circuit is monitoring a fire alarm system that is not picking up any signals, a trouble signal will show up on the control panel.

Q. How can you tell the difference between a trouble and alarm scenario?

Anderson: Systems today are fully addressable. That means each detector is identifiable by its signal so we know exactly what’s happening at that location. If a detector does go off, it doesn’t put the whole building into alarm right away. But if the same detector goes off again in a certain amount of time or if another detector in the area goes off, the system will put the building into alarm. That’s what’s called alarm verification—it’s one of the biggest advantages of today’s systems.

Mulkerrin: Let’s say there’s a bad detector and a loss of signal. The system tells you exactly where the problem is so maintenance personnel can go to the location and check the detector by blowing canned smoke into it to test it. If the detector doesn’t pick up the smoke, they’ll know it’s not working properly and change it out right there. Once the new detector is installed, the system will pick up the input.

Q. What were the capabilities before addressable technology?

Anderson: Before addressable technology, we had conventional systems. Instead of each detector having a specific address, we’d have a string of detectors on one loop. If any of those smoke detectors went off, it would set off the whole zone. You actually wouldn’t know the exact spot—just a general area. You’d get feedback like corridor 45, level two, east wing—much more generic than the information we receive today.

Addressable technology has really taken off in the past few years, and the price has come down too. So there’s very little use for conventional systems now. As a matter of fact, most fire departments won’t even let us use them any more—at least in the major cities. Residential is probably one of the few areas where conventional is still acceptable.

Q. How do these new systems communicate with the fire department?

Mulkerrin: There’s a couple of ways you can do communication. Right now, they’re testing whether they can do it over the Internet. Some facilities and jurisdictions will allow you to do that. But the typical way is having a fire  alarm master box.

The way that works is there’s a line that runs through the city or campus and a facility’s master box is tied onto it and each master box has a unique address. If a station is pulled or the fire alarm control panel tells the master box to go off, it automatically notifies the fire department. Another way is to have the system report to a central station—like an ADT—and sometimes there’s even a hard link between the two. When the system goes into alarm and it’s reported to the central station, they call the authorities.

Q. Do different building uses dictate the type of system you design?

Anderson: Take for example a hospital where people are incapacitated in some way. That’s really the highest level of safety, in our opinion, because you cannot evacuate the patients very easily. From a life and safety standpoint, that’s really the most critical. And then you get into clean rooms and industrial locations where you’re dealing with chemicals. Some of these areas have HPM—hazard production materials—that’s where you have highly flammable materials that necessitate a higher hazard classification.

Q. How do the systems vary for different uses?

Anderson: For a wet sprinkler system, it’s the volume of water that’s applied to the hazard. When you get into chemicals and materials that are reactive with water, in that case you need to go with what’s called a gaseous fire suppression system and, in some cases, foam.

The NFPA does provide some guidelines. Depending on the quantities of combustibles, this requires you to increase the hazard classification. For example, an office area would be considered a light hazard, whereas a storage room with papers piled up to the ceiling is an ordinary hazard. That’s really about the amount of water that is applied to a given area. We define that for the contractor.

Q. Can you explain that?

Anderson: You’ll have sprinklers more closely spaced and they will be applying more water to areas with a higher hazard classification.

As engineers, we look at what we call a remote area. Typically, for a light-hazard remote area—like office space—you need to apply water at a rate of 0.15 gallons per minute over 1,500 square feet. That affects the piping system in the way you hydraulically size it. You take an area approach, as opposed to looking at one sprinkler.

Q. How does building type affect the electrical side?

Mulkerrin: Smoke detection coverage is much more stringent in hospital, residential, hotel occupancies, dormitories or anything like that. In commercial space, smoke detection isn’t required in every room. Of course, you have it in electrical rooms, storage rooms, mechanical rooms, but in an office building, people are going to notice the smoke, so they are not required everywhere.

But when you design for a building where people are sleeping, you have detection in every room. As far as the notification goes, there are certain candela rating requirements—that’s the amount of light from the strobes and the ambient levels of light. They’ll actually measure that right at the pillow on the bed. NFPA really concentrates their rules on making sure that the person sleeping in the bed will wake up.

Q. In general, how prepared are buildings for today’s conditions?

Anderson: Today’s buildings are generally safe. Certainly, there’s always room for improvement, but we’ll never overcome human error. Even with 9/11, not much change has resulted from updated code. It takes so much time for some of these codes to react to real-world events, but you have to remember, code is a minimum. What we refer to as “good engineering practice,” that’s above code. Overall, advancements in electronics have made buildings safer … much safer than 10 years ago.

National and local safety standards and codes address the ability of air duct systems to transfer smoke, toxic gases and flame from area to area in educational facilities. It is this threat that is confronted with the use of duct smoke detectors, because oftentimes, in fire scenarios, smoke can be of such quantity that it poses a serious hazard to the safety of people several floors removed from the actual fire.

It is critical, therefore, that educational facility managers, engineers and architects understand that the primary purpose of duct smoke detection in schools is to prevent injury, panic and property damage by reducing the spread and recirculation of smoke.

Preventing Injury and Damage

A duct smoke detector is a device or group of devices used to detect the presence of smoke in the air stream of ductwork sections of the heating, ventilating and air conditioning (HVAC) air handling systems used in educational facilities.

Duct smoke detection is extremely useful in preventing injury and property damage in schools, universities or other types of educational facilities. It can serve to protect a school’s air conditioning system from fire and smoke damage, and can also be used to assist in equipment protection applications, for example, in the ventilation/exhaust duct work leading to the areas that house mainframe computers and tape drives in university settings.

Duct smoke detection can also be the first line of defense to shut down the system’s blowers and ensure dampers are actuated when there is a fire. For instance, should an HVAC fan motor overheat, the resulting smoke is sensed by the duct smoke detector installed in the main supply duct. The duct smoke detector is equipped with an auxiliary relay that immediately cuts power to the fan motor before significant amounts of smoke can be distributed to hallways and classroom areas.

Or, for example, if a fire starts on the second floor of a dormitory, and the HVAC system serving the second floor also serves floors one through four, the smoke will also spread to those floors. If area smoke detectors are not provided, the only means of automatic detection are the duct smoke detectors located in the return air ducts on each floor ahead of the main return plenum. The quantity of smoke in the duct eventually reaches proportions sufficient to alarm the second floor duct smoke detector, which transmits a signal to the dorm’s fire alarm system. Evacuation signaling and HVAC shutdown functions are then provided by the duct detector’s auxiliary relay contacts. In these and other situations, duct smoke detection devices are proven effective in helping prevent injury and property damage.

Installation, Maintenance and Testing

An HVAC system supplies conditioned air to virtually every area of a building. Thus, smoke introduced into this air duct system has the potential to reach the entire building. Because smoke detectors designed for use in air duct systems are used to sense the presence of smoke in the duct, it is critical that they are properly installed, maintained and tested.

NFPA 90A,“Standard for Air Conditioning and Ventilating Systems,” requires that smoke detectors listed for duct installations be installed at a suitable location in the main supply duct on the downstream side of the filters to automatically stop the supply fans in systems more than 2,000 cubic feet per minute (cfm). For systems more than 15,000 cfm, additional detectors are required in the return system of each floor, at the point of entry into the common return, or a system of smoke detectors is required to provide total area coverage.

Smoke detectors are designed to be as maintenance-free as possible. However, dust, dirt, and other foreign matter can accumulate inside a detector and change its sensitivity. This is especially true with duct-type smoke detectors in educational facilities. They can become more sensitive, which may cause unwanted alarms, or less sensitive, which may reduce the level of protection. Both are undesirable. According to Chapter 10 of NFPA 72, 2002 Edition, duct smoke detectors should be tested upon acceptance and re-tested annually. Always check your local code requirements to determine if more frequent testing is required.

Under normal conditions, detectors require routine maintenance at least twice a year, or more frequently in dirtier than normal environments. Notify the proper authorities that the smoke detector system is undergoing maintenance and that the system will be temporarily out of service. It is also imperative that the zone or system undergoing maintenance is disabled to prevent unwanted alarms and possible dispatch of the fire department.

Most duct smoke detectors have detector sensors that can be accessed for cleaning. To clean the sensors, remove dust from all openings on and around the sensor, the sampling tube and the exhaust tube. Some detectors can be removed for more thorough cleaning, if necessary.

It is also important to test each detector’s sensitivity. If a detector’s sensitivity is within specifications, nothing further needs to be done. If the detector’s sensitivity is outside its listed specifications, either clean or replace the detector according to the manufacturer’s recommended procedures. Upon completion of any testing or maintenance procedures, be sure to restore the system and notify the proper authorities that the system is back in service. Other duct smoke detector maintenance issues that should be routinely checked include:

• Holes or cracks in duct work near the vicinity of the detector
• Air leaks where the detector housing or sampling tubes are attached to the duct
• Wiring terminal screw tightness

Understanding the purpose of duct smoke detectors in educational facilities, as well as the importance of their proper installation and care, is the key to protecting property and saving lives.

Fires on campus and at off-campus student housing across the country reveal a dangerous trend. According to The Center for Campus Fire Safety, from January 2000 to April 2005, 57 off-campus and 18 on-campus fire fatalities occurred. No one wants to sound the alarm prematurely, but statistics involving 75 fatalities due to fires are hard to ignore — especially when almost all involved facilities without fire sprinkler protection.

Such trending of fire loss has produced a myriad of legislative initiatives. While fire sprinkler legislation is now pending in many states, only Wyoming, New Jersey, Delaware, Illinois and Wisconsin currently require sprinkler retrofits at residential facilities on campus.

On the federal level, lawmakers are considering actions that would require the U.S. Department of Education to gather information about the number and location of sprinklers in dorms and allocate $500 million over five years to help colleges install sprinklers in dormitories. In the U.S. Senate, a bill has been introduced to provide a depreciation tax break for automatic fire sprinkler system retrofits, which would be an incentive for owners of off-campus housing. Whether federally mandated or not, colleges across the country are now taking a serious look at installing fire sprinkler systems for the protection of their students.

System Sensor, a leader in the fire protection device industry, has been at the forefront of developing superior fire detection, fire sprinkler monitoring and notification products that protect property and save lives. This article offers a brief overview of System Sensor’s line of fire sprinkler monitoring devices for use in colleges, residences or any other facility where fire sprinkler systems are installed.

Monitoring Solutions for Wet and Dry Pipe Fire Sprinkler Systems

Industry-wide, wet pipe systems are the most common type of fire sprinkler system installed. By definition, wet pipe systems are constantly filled with water. When a sprinkler head opens during a fire, water immediately begins flowing through the fire sprinkler system pipe and out of the sprinkler head. Per the National Fire Alarm Code, NFPA 72, an alarm must then signal within 90 seconds of water flow. Waterflow detectors are, therefore, installed to initiate an alarm condition when there is a flow condition within the fire sprinkler system.

System Sensor offers waterflow detectors to accommodate installations for 2-inch through 8-inch risers, as well as 1-inch threaded waterflow detectors for residential fire sprinkler systems and branch line pipes that are often found in student apartments and fraternity houses. System Sensor WFD series waterflow detectors are NEMA 4  rated, making them ideal for indoor and outdoor use. And their field-replaceable terminal blocks and timer/retard assemblies are a real time saver.

For those cases where a wet pipe system may not be appropriate, such as a sprinklered area that may be prone to freezing, a dry pipe system may be used. In a dry pipe arrangement, the system is normally pressurized with air. This air pressure holds a clapper in place to prevent the water from entering the system. When a sprinkler head opens during a fire, the air is initially released. Once the system pressure can no longer hold back the water, the system pipes fill with water, which then discharges through the open sprinkler head. It is the change in air pressure, detected by a pressure switch, that initiates an alarm signal.

To accommodate dry pipe systems, System Sensor offers a complete line of EPS pressure switches. The EPS series is available in a variety of pressure ranges, including 4 to 20 PSI, 10 to 100 PSI, and 10 to 200 PSI, to accommodate virtually any application.

Another critical element of the fire sprinkler system that requires monitoring is the control valve. Regardless of whether the fire sprinkler system is wet or dry, control valve supervision is required to minimize the likelihood that the control valves are closed or opened by unauthorized personnel.

Fire sprinkler system control valves come in various styles and sizes. To accommodate the most common configurations, System Sensor offers OSY2 and PIBV2 supervisory switches. These are intended to monitor the open position of an outside screw-and-yoke gate valve and post indicator/butterfly valves. For other unique installations, System Sensor offers its PSP1 plug-in supervisory switch designed for applications where no other type of listed valve supervisory switch can be used, such as non-rising stem gate valves and ball and angle valves.

Although much more comprises a fire sprinkler system — just as the fire sprinkler system is a component of the overall life-safety system — the importance of the monitoring products that ensure the activation of the system is immense. Consequently, System Sensor’s waterflow products are essential to the proper protection of life and property.

InnovairFlex provides a full range of accessories that expand the versatility and usability of InnovairFlex duct smoke detectors into a wide range of applications. This increased product flexibility enables distributors to reduce product SKUs and free up valuable shelf space. In addition, increased versatility and usability enable installers and technicians to save time and money on installation, testing and maintenance.

One innovative accessory for InnovairFlex is the new DST sampling tube. These plug-in sampling tubes install from the front or the back of the detector, without tools, to speed and simplify installation. The sampling tubes come in the following lengths: 1, 1.5, 3, 5 and 10 ft.

Another new set of accessories is the RTS2 and RTS2-AOS multi-signaling devices. These accessories enable quick, convenient inspections at eye level and effective audible and visible notification options. RTS2 accessories are compatible with all duct smoke detector devices and enable users to:

• Discretely monitor two sensors from the same location when 4-wire InnovairFlex duct smoke detectors are configured in a 2:1 setup.
• Read color-coded LED indicators to quickly and easily identify the status of connected duct smoke detectors. Status indications include Standby (green), Trouble (amber), Maintenance (amber blink) and Alarm (red).
• Use the integral key switch to quickly perform multiple functions from a single location, such as selecting the desired sensor, enabling a test/reset button and enabling sensitivity reading.
• Enable convenient sensitivity readings using the SENS-RDR remote sensitivity reader (sold separately) for hard-to-reach duct smoke detectors.
• Select a continuous or temporal tone to meet specific application needs.
• Use the Add-On Strobe (AOS) (included on RTS2-AOS model) to provide visible notification capabilities when required.

NEMA 4-rated InnovairFlex watertight duct smoke detectors are built to operate in the most challenging conditions without the need for bulky or costly enclosures. These detectors can operate in airflow speeds from 100 to 4,000 feet per minute, temperatures from -4°F to 158°F and humidity ranges from 0 to 95% (non-condensing). In addition, a watertight, UV-resistant housing provides protection against falling dirt, rain, windblown dust, splashing and hose-directed water. These features allow operators to mount the detector to rooftop HVAC equipment or use the detector in other harsh environments.

InnovairFlex watertight models are compatible with all InnovairFlex accessories and include all the same time- and money-saving features as the entire InnovairFlex line.

Speakers have been particularly susceptible to ground faults because they take up more room in the back box, sometimes forcing installers to crush or pinch wires when pushing the wired speaker into the back box to be mounted. The plug-in design of SpectrAlert Advance reduces ground faults and associated costs by enabling installers to pre-wire mounting plates and dress wires before connecting the speakers. To further reduce ground faults, the speakers have a protective cover that eliminates exposed speaker components and prevents nicked wires. In addition, a shorting spring on the mounting plate tests wiring continuity to provide instant feedback to installers during the installation.

SpectrAlert Advance Speakers transmit the clear, intelligible messages needed during emergency situations. The SP line of high-fidelity speakers can be selected for crisp, clean signals, and the SPV line of high-volume speakers can be chosen to command attention in environments with high ambient noise levels.

Like all products in the SpectrAlert Advance line, Speakers and Speaker Strobes include all the innovative features that make SpectrAlert Advance the broadest, most versatile audible/visible notification appliances in the industry.

For example, field-selectable candela settings and 12- or 24-volt operation make a single device adaptable to a wide range of applications, simplifying inventory, specification and installation. In addition, SpectrAlert Advance Speaker Strobes offer the lowest current draw available on all candela settings, with measurable savings especially on the high candela models. This enables more appliances to be installed on a single circuit, reducing installation time and project costs.

Following are features available throughout the SpectrAlert Advance product line:

• Plug-in design
• Electrical compatibility with legacy SpectrAlert products
• Field-selectable candela settings on wall and ceiling units
• Universal mounting plate fittings for both wall- and ceiling-mounted units
• Compatibility with System Sensor synchronization protocol
• Automatic selection of 12- or 24-volt operation at 15 and 15/75 candela
• Inclusion of an optional tamper-resistant Torx head screw