Choosing the right power supplies for security installations

Download PDF version

Determining the power requirements of every systems product taking into account their integration with one another is critical

Selecting the optimum power supply for a system is critical to an installation

When it comes to selecting power supplies, knowledge is power. Determining the power requirements of every systems product, taking into account their integration with one another is critical to ensure that you are selecting and installing the power solutions most appropriate for your installation. Such information will enable you to select the power supplies that will be required to keep your security system running efficiently in the long run. Paul Rizzuto, Technical Sales Manager, Altronix Corp outlines some of the key factors to consider when choosing the right power solution for security installations - including those of video surveillance systems and access control systems - and fire alarm systems.

Questions to consider when selecting the optimum power supply

Before commencing the evaluation and selection process, three fundamental questions/issues need be addressed:

Approvals and conformance to norms:

Are there any specific agency approvals that the installation must conform to?

Each state, county and even municipality has their own requirements regarding agency approvals. There are a variety of compliance issues such as UL listings for video, access control and fire/life safety that need to be adhered to along with specific local codes. It's imperative that you check with the local AHJ (Authority Having Jurisdiction) to find out what agency listings you must conform to during the design process to assure your security system is in compliance before installing any components and power supplies.

Features required:

What are the application specific features required for the installation?

Selecting power supplies for a security or fire alarm system is a complex process due to a number of variables

Before starting the design process, a comprehensive analysis of the facility's security systems are required to determine feature sets of the power supplies. Up until recently, selecting power supplies often required the need to combine various components to deliver the functionality desired. For example, does the system need battery back-up in case of a power failure? All that has changed with the introduction of a new breed of integrated power solutions that deliver both cost and installation advantages.

Quantity, location and power requirements of the security system components

What is the number of devices in the system, the power requirements for each, and their physical location?

This information is necessary to determine the size and quantity of the power supplies, how many security devices they will run, and where they will be physically located. It is always a good rule of thumb to add 20% more power to your calculations as a safety factor.

Power consumption is a primary issue when configuring fire alarm systems

Alarm signal generation is a key consideration when dealing with power consumption in fire alarms systems

Dealing with power consumption issues in fire alarm systems

Power consumption is a primary issue when configuring fire alarm systems. One of the most critical considerations revolves around how alarm signals are activated. When an alarm condition exists, Notification Appliance Circuits (NAC) are output from the Fire Alarm Control Panel (FACP) to activate notification appliances such as strobes and horns commonly used to indicate an emergency situation. The number of notification appliances to be activated, along with the current draw for each device and its distance from the FACP, sometimes makes the deployment of NAC Power Extenders a necessary system component.

For example, in large commercial installations or multi-tenant buildings, the total current draw of the notification appliances may well exceed the power output of the FACP. In these instances, one or more NAC Power Extenders need to be installed for those notification appliances where the wire runs are too long for the FACP to deliver sufficient power.

Features to consider when selecting a NAC Power Extender:

Number of Class A or Class B indicating circuits.
Total power rating (ex. 6.5 amp, 8 amp or 10 amp).
Number of Aux. power outputs with or without battery backup.
Programmable outputs:
- Synchronization
- Temporal Code 3
- Input to output follower mode.
Enclosure capacity:
- Room for battery backup
- Ample knockouts and room for wiring
Agency approvals UL, MEA, CSFM and FM.

NAC Power Extenders are available with programmable features that maintain horn/strobe synchronization by either producing internally generated sync protocols utilized by major signal manufacturers, or by electronically repeating these sync protocols from the FACP outputs.

Power supply requirements for access control systems - key standards to follow

any device or system intended to actuate the locking or unlocking of exits, must be connected to the facility's fire alarm system so that all doors will release when an alarm signal is generated

To ensure safety any device designated to lock or unlock an exit must be connected to the fire alarm system

Access control systems manage entry and exit points at a facility by means of controlled locking devices. NFPA (National Fire Protection Association) requires that any device or system intended to actuate the locking or unlocking of exits, must be connected to the facility's fire alarm system so that all doors will release when an alarm signal is generated.

To comply with NFPA requirements, there are two classifications of locking devices that need to be addressed: Fail-Safe and Fail-Secure. Fail-Safe locking devices such as magnetic locks release when they lose power. Fail-Secure locking devices such as electric strikes unlock when power is applied and may be manually released from inside a secured area. This determines the manner in which your power solution removes or provides power and the sequence and timing of each action.

Access control power supplies come in both AC and DC versions and some provide multiple voltages simultaneously. Features include independently trigger controlled Fail-Safe/Fail-Secure outputs, power supervision, battery charging and fire alarm interface. Wall and rack mount models are also available.

To comply with NFPA requirements, there are two classifications of locking devices that need to be addressed: Fail-Safe and Fail-Secure

Some systems may also require the installation of panic hardware devices. Upon activation, the devices' high current power demand can reach up to 16amps, but not all power supplies can handle these high inrush currents. As a result, you need to specify a power supply designed for this type of application. Some operate a single panic hardware device and require optional modules to add features like timing functions, output relays, fire alarm disconnect, or power for additional panic hardware devices. Therefore, these "base" models almost always require additional modules to deliver the functionality you need and may not be cost effective. More advanced models offer integrated features and supply a comprehensive solution. In addition to the convenience of these integrated devices, they are highly cost efficient with respect to total cost of ownership and installation.

Video surveillance systems - typical power consumption guidelines

Video surveillance systems typically run 24/7/365 placing high demands on power supplies. These video power supplies need to deliver a clean and consistent source of 24VAC or 12VDC power to assure uninterrupted operation. Depending on the video component's specific power requirements and its location, there is a wide selection of power supplies to select from. They can be wall or rack mounted, designed for use indoors or outdoors, and feature AC or DC outputs. Configurations typically range from 1 to 32 outputs and some models offer additional features like 115 or 230VAC input with current ratings as high as 25 amps, power LED indicators, and PTC or fused protected outputs. Certain models provide both 24VAC and 12VDC to power both types of surveillance cameras simultaneously.

Temperature differences due to change of seasons, day or night, can often be extreme and can have a direct affect on the performance of both the video components and the power supp

Environmental conditions can affect the performance of video components and the power supply when situated outdoors

A few additional variables to consider when selecting video surveillance power supplies include:

Environmental conditions: Temperature differences due to change of seasons, day or night, can often be extreme and can have a direct affect on the performance of both the video components and the power supply when located outdoors. Enclosures for outdoor power supplies should be rated to withstand the elements.

Ground Isolation: In some cases, the surveillance cameras are not equipped with internal electrical isolation. Should this be the case, it's important to specify a power supply with this feature.

Video Transmission Systems: For years, the use of structured cable has been an inexpensive method for transmitting video and data between head end equipment and camera systems. The introduction of UTP transceiver hubs with integral camera power make it possible to transmit both video and data via structured cable along with the power needed for the cameras. This is accomplished via video balun/combiners which pass the power and data to the camera and send the video back to the head end equipment.

New highly versatile devices with integral power provide system designers with a highly integrated solution. This new breed of integrated device greatly reduces the time and expense of configuring and installing separate components while helping to minimize bandwidth requirements for large security systems.

Paul Rizzuto
Technical Sales Manager
Altronix Corp

Download PDF version

Related companies
Altronix

Related links
Altronix Power supplies & batteries

Related categories
CCTV cameras
Multiplexers
Power supplies & batteries
Intruder alarm system control panels & accessories
Access control systems & kits
CCTV Switchers & Switches
IP cameras
Dome cameras

View all news from
Altronix

In case you missed it

Which technologies will disrupt the security industry in the second half of 2020?

The first half of 2020 has been full of surprises, to say the least, and many of them directly impacted the physical security market. The COVID-19 pandemic created endless new challenges, and the physical security market has done our part to meet those challenges by adapting technology solutions such as thermal cameras and access control systems. In the second half of 2020, we can all hope for a return to normalcy, even if it is a “new normal.” In any case, technology will continue to play a big role. We asked this week’s Expert Panel Roundtable: Which technologies have the greatest potential to disrupt the security industry in the second half of 2020?

What do you need to know about thermal imaging cameras?

As businesses, schools, hospitals and sporting venues look to safely reopen in a COVID-19 world, thermal imaging systems will play a critical role in helping to detect and distinguish skin temperature variations in people. Thermal surveillance, a mainstay of traditional physical security and outdoor perimeter detection, is now being deployed to quickly scan employees, contractors and visitors as part of a first line of defense to detect COVID-19 symptoms. In the coming weeks and months, the security industry will look to implement thermal camera solutions for customers, yet many questions remain as to the differences between different system types and how to properly install thermal imaging cameras. In this Q&A, Jason Ouellette, Head of Technology Business Development for Johnson Controls, answers several of these questions. Q: What are some of the different thermal imaging solutions available in the market to detect an elevated temperature in a person? For the general market, there are three types of these thermographic screenings. There is the handheld device, which is typically lower cost, very portable, and very easy to use. Typically, this is a point and shoot type of device, but it requires you to be three feet or less from the person that you're screening, which, in today's world, means the user needs to wear protective personal equipment. For the general market, there are three types of these thermographic screenings The second type of solution would best be described as a thermal camera and kiosk. The advantage of this system over a handheld device is this can be self-service. An individual would go up to and engage with the kiosk on their own. But many of these kiosk type solutions have some integration capability, so they can provide some type of output, for either turnstiles, or physical access control, but not video management systems (VMS). Some of the downside of this type of system is that it’s less accurate than a thermographic solution because it does not have a blackbody temperature calibration device and the readings are influenced by the surrounding ambient temperature, called thermal drift. So instead of being able to achieve a ±0.3ºC accuracy rating, this system probably provides closer to ±0.5ºC at best. Some of these devices may be classed as a clinical thermometer with a higher degree of one time accuracy, but do not offer the speed and endurance of the thermographic solution for adjunctive use. And then there are thermal imaging camera systems with a blackbody temperature calibration device. These types of systems include a dual sensor camera, that has a visual sensor and a thermal sensor built right into the camera, along with a separate blackbody device. This provides the highest degree of ongoing accuracy, because of the blackbody and its ability to provide continuous calibration. These systems can provide much more flexibility and can offer integrations with multiple VMS platforms and access control devices. Q: When installing a thermal imaging camera system what is the most important element to consider? Camera placement is critical to ensure the system works as expected, however the placement of the blackbody device which verifies the correct calibration is in place is equally as important. If the customer wants to follow FDA medical device recommendations for camera placement, both the height of the camera and the blackbody as well as the distance between these devices should comply with the product installation instructions. This takes into account the device focal range and calibration parameters in addressing the distance from the person undergoing the scan. Also, integrators should minimise camera detection angles to ensure optimal accuracy and install cameras parallel with the face as much as possible, and again in compliance with installation instructions. Integrators should minimise camera detection angles to ensure optimal accuracy The blackbody should be placed outside of the area where people could block the device and located more towards the edges of the field-of-view of the camera. You need to keep in mind the minimum resolution for effective thermographic readings which is 320 by 240 pixels as defined by the standards. To achieve this, you would need to follow medical electrical equipment performance standards driven by IEC 80601-2-59:2017 for human temperature scanning and FDA guidelines. Within that measurement, the face needs to fill 240 x 180 pixels of the thermal sensor resolution, which is close to or just over 50 percent of the sensor’s viewing area typically, meaning a single person scanned at a time in compliance with the standards for accuracy. Along with height and distance placement considerations, the actual placement in terms of the location of the system is key. For example, an expansive glass entryway may impact accuracy due to sunlight exposure. Installations should be focused on ensuring that they are away from airflow, heating and cooling sources, located approximately 16 feet from entry ways and in as consistent of an ambient temperature as possible between 50°F and 95°F. Q: Once a thermal imaging camera system is installed, how do you monitor the device? There are several choices for system monitoring, depending on whether the solution is used as standalone or integrated with other technologies, such as intrusion detection, access control or video systems. For standalone systems, the ability to receive system alerts is typically configured through the camera’s webpage interface, and the cameras include abilities such as the live web page, LED display for alerting, audio alerts and physical relay outputs. When done right, these features will all follow cybersecurity best practices which is important for any network solution today, including changing default passwords and establishing authentication methods. The ability to receive system alerts is typically configured through the camera’s webpage interface These types of thermal cameras can also integrate with turnstile systems, VMS platforms and access control systems. This is typically done through the integration of a relay output, activated by a triggered temperature anomaly event on a thermal imaging camera which can then be used for activities such as locking a turnstile, or through access control and video systems to send an email or provide an automated contagion report for contact tracing. These capabilities and integrations extend the monitoring capability above that of the standalone solution. The camera can be configured to monitor a specific range of low and high alerts. Users can determine the actions that should be taken when that alert exceeds the preset low or high threshold. These actions include things like a bright and easy-to-see LED can provide visual notification through pulsing and flashing lights as an example. Q: What about system maintenance? Does a thermal imaging camera require regular service in order to operate accurately? First it’s important to make sure the system is calibrated. This can be done after the unit stabilises for at least 30 minutes to establish the initial reference temperature source known as the blackbody. Calibrations conducted before this warm up and stability time period can throw off accuracy. Also, as part of your system maintenance schedule you will want to perform a calibration check of the blackbody device every 12 months, along with following recommendations of the FDA and IEC. If you install the solution and don’t perform maintenance and the blackbody calibration certificate expires, over time there’s a risk that the device will experience drift and a less accurate reading will result. There’s a risk that the device will experience drift and a less accurate reading will result Q: What final pieces of advice do you have for either an integrator who plans to install a thermal imaging camera system or an end user who plans to invest in this solution? Before you buy a thermal imaging camera check to see if the manufacturer ships the camera with a calibration certificate. Also, become familiar with FDA’s guidance released in April 2020, Enforcement Policy for Telethermographic Systems During the Coronavirus Disease 2019 (COVID-19) Public Health Emergency. This document places thermal/fever products for adjunctive use under the category of a Class I medical devices and subject to its regulatory control. Driven by these regulations and categorisation, users need to understand specifically what is required to meet the required level of accuracy for successful detection. While thermal imaging camera systems are more complex than traditional surveillance cameras, they can prove to be a valuable resource when set up, configured and maintained properly.

Recognising the importance of security officers to promote safety

The general public doesn’t give much thought to the important role of security officers in creating and promoting safer environments. The low-profile work of security officers is vital to protecting people, places and property. During the pandemic, newer aspects to that role have emerged. Security personnel have been called on to perform diverse tasks such as managing queues at the supermarket, safeguarding testing centres and hospitals, ensuring food deliveries, and supporting police patrols. The British Security Industry Association (BSIA) and two other organisations in the United Kingdom are joining forces to raise awareness of the work of security officers and to recognise the vital importance of the duties they perform. BSIA, a trade association, includes members who are responsible for 70% of privately provided UK security products and services, including security guarding, consultancy services, and distribution and installation of electronic and physical security equipment. BSIA, the Security Institute and the Security Commonwealth Joining BSIA in the awareness campaign are the Security Institute, a professional security membership body; and the Security Commonwealth, which is comprised of 40 organisations from across the security landscape with common objectives to build professionalism, raise standards and share best practices. “The recognition of security officers as key workers is the start of a re-appraisal of what service they provide to the community in keeping the public safe and secure,” says Mike Reddington, BSIA Chief Executive. “As we exit lockdown and have to navigate public spaces again, [security officers] will have a crucial role in supporting public confidence. We are working closely with the Police and all other public bodies to find the best way to achieve this.” Security officers acknowledged as key workers The campaign will showcase security professionals as a respected, valued, professional service provider and a key worker that is acknowledged and embedded in daily lives. The British Security Industry Association (BSIA) and two other organisations in the United Kingdom are joining forces to raise awareness of the work of security officers “Great effort has been invested in the professional standards and capabilities of frontline [security] officers, and they have proven their worth during the coronavirus crisis in the UK,” says Rick Mounfield, Chief Executive, the Security Institute. “They, along with the wider security sector, deserve to be recognized, respected and appreciated for the safety and security they provide across the United Kingdom.” “[We are working to] build professionalism, raise standards and share best practices, and I hope this campaign can make more people recognise the changes we have all made and continue to make,” says Guy Matthias, Chairman of the Security Commonwealth (SyCom). The industry will be reaching out to companies, professionals, and organisations in the sector to participate in the campaign. The hope is that, over the coming weeks as lockdown is eased, the industry can play its part to ensure that the country emerges with confidence to start to recover and build for the future. Private security more important than ever The campaign will showcase security professionals as a respected, valued, professional service provider Across the pond in the United States, law enforcement professionals are facing a crisis of confidence during a time of civil unrest as protestors call to “defund the police” and to otherwise undermine and/or recast law enforcement’s role in preserving the peace and ensuring public safety. If an upshot is that public policing is starved of resources, the role of private security to supplement their mission is likely to increase. In short, the role of private security is more important than ever on both sides of the Atlantic. Public recognition of that role is welcome, obviously. In any case, the importance of their role protecting people, places and property has never been greater.