Protectowire: Linear Heat Detection

Posted by ORR Protection on Feb 16, 2021 9:52:04 AM

Protectowire's, Gary Paul breaks down linear heat detectors, their applications, accessories, & their uses in detecting heat or a sudden rise in temperature.


Video Transcript:

Hello, and welcome to today's presentation. I want to thank you for taking time out and being here with us.
My name is Gary Paul, and I'm the regional sales manager for the US and Canadian markets here at Protectowire. I'm also a member of the national fire protection association and the society of fire protection engineers. Today, I'm going to be speaking to you about Protectowire series of linear heat detectors, their apps, their application, and some of the common accessories associated to help provide a better understanding of the products available and their effective uses. Let's start with a quick introduction, Protectowire linear heat detectors are a series of fixed temperature devices. Their unique design enable their use in several challenging applications where conventional detectors simply cannot reach, except for fiber-optic Protectowire linear heat detectors are categorized as a digital device, which is simply to say the condition of the device is either on or off. The first linear heat detector was invented back in 1938 by Gerald Holmes, the founder and original owner of Protectowire and has been listed with both UL and FM.

Since the 1940s, linear heat detection can be best described as continuous chain of spot heat detectors. With the ability to sense heat or sudden increase in temperature anywhere along its length. A common misconception is linear heat detection comes only in one form. I'd like to take a quick moment to introduce the family of linear heat detection that has been developed over the years to meet a variety of challenges. To start, there is the PHSC series detector, which stands for Protectowire Heat Sensitive Cable. This is the product most widely used, and the detector that most relate to when they hear the name. Comprised of two steel conductors, the PHSC series can be integrated into any conventional or addressable system. However, there are limitations when considering equipment, which we'll get into an a few moments. Next is the PLR series, which stands for Protectowire low resistance, same construction as PHSC, PLR series adds copper coated conductors to reduce the cable's overall resistance value from 0.185 ohms per foot, which is the standard resistance values value of steel, to .058 ohms per foot. That's roughly a two thirds reduction in resistance value. Lower resistance equals longer runs. The most recent development in linear heat detection is CTI, which stands for Confirmed Temperature Initiation. Replacing the steel core conductors of our standard PHSE series with copper and constantan creates a type T thermocouple providing us the ability measure physical temperatures at the location of the fault. Through the required CTM five 30 interface module, we can now probably initiation temperature and compare it to the temperature of the fault. Through this process, we can discriminate between a mechanical failure and an actual true heat event. And lastly, we have fiber optic, which is widely viewed as the next generation and linear heat detection standard digital linear heat detection detection is considered a passive device, meaning that it sits in a ready state waiting for the fixed temperature to be achieved before activating fiber technology.

On the other hand is an active system that reports real-time temperature profiles, anywhere along its length, up to 10 kilometers. That's a little over 32,000 linear feet off a single fiber, and then can be further segmented or zoned into 256 unique partitions anywhere along its length, which is all done through software. As a reference in the previous slide, integrating linear heat onto other manufacturer's control equipment can become something of a challenge, depending on some of the electrical values of the equipment we're connecting to. Standard linear heat detection is capable of being supported through any initiating device circuit or IDC, regardless of manufacturer. Where the challenge lies is the output value of the IDC and how much linear heat can actually be supported. As I mentioned, steel has an inherent resistance value of 0.185 ohms per foot. And adding copper reduces this value to 0.058 ohms per foot.

This slide provides a good illustration of exactly how much these IDCs can directly impact the zone coverage capabilities connect and direct to the modules. In this example, we show two different addressable modules the first with output capabilities of a hundred ohms and the second with 440 ohms by dividing the IDCs output value by the resistance value of the detector, we get some surprising numbers. With a hundred own IDC example. Our calculations show, we're able to support up to 500 linear feet of PHSc and almost 1700 feet of PLR. That's a good example of how that resistance value can exactly extend out your zones. We see the similar limits in the 440 home IDC, but our lengths are longer due to the electrical properties of the module. Now take into consideration that coming off of one of Protectowire's conventional panels, we can support it from 5,000 to 10,000 linear feet.

And you begin to see the challenges with presenting a viable solution with the variety of addressable modules and the requirements in larger applications to address this issue. The Penn 530 interface module was introduced depending on the manufacturer. The addressable IDCs can range anywhere from 25 ohms up to 1500 ohms output. This output value directly impacts the total linear footage that can be supported through the Penn 530 interface module. We can now tie into anyone's control equipment, conventional or addressable, and support up to 6,500 linear feet of standard linear heat detection or our PHSc series. Other features include class a or class B monitoring, integrated alarm point location, communication to the main panel through form C status relays or four to 20 million amp outputs. And we've also included the 64 event history file, as well as mod bus serial communication, like the Penn five 30, the CTM 530 is specific to our CTI detector and a required component with every installation.

The CTM five 30 acts as the brain of the CTI system, providing the false alarm discrimination by comparing the pre-programmed initiation temperature with the physical temperature at the location of the fault. If the temperature at the fault location does not meet the initiation criteria, the system remains in a fault condition. In a class, a configuration, you maintain continuous coverage throughout the zone. In a class B set up, you lose only the section beyond the fault, everything up to and including the fault remains active. As the leader in linear heat technology, we're constantly looking at areas to expand product capabilities. Two recent introductions of the perfect bookends to that endeavor with the recent introduction of both our highest and lowest activating detectors to date the PLR 500 CR and the CTI one 35 XLT, both products address very specific needs within the marketplace. The PLR 500 was developed to focus on applications that are constantly exposed to extreme high temperatures, furnace, work, kitchen applications, things of that nature. The CTI one 35 XLT along with its sister in our PHSC series was brought about to address the extreme conditions of industrial freezers and the ability to provide a pre action system that will react before the sprinkler heads.Couple this with CTI technology, and you now had the perfect solution for industrial freezers of all shapes and sizes.

This brings us to applications within the special hazards community. Linear heat detection is a niche element providing protection primarily in industrial settings and is commonly installed to provide open area protection within UL and FM guidelines, it's listed in the same category as spot heat detectors with similar open area listed spacing, typically 50 feet per UL and 25 to 30 feet per FM, given its unique construction, linear heat can also be woven in close proximity or in direct contact with the atom or apparatus being protected. This is typically referred to as proximity detection and where linear heat really shows its versatility. What you're seeing here as some of the more common industries where linear heat is applied, of course, within these industries lie a broad array of individual applications that are ideal for this technology. Through the remainder of the presentation, I'll explore some of these areas as well as common accessories and installation nuances associated with each. Within the power industry alone.

We can point to nearly a dozen different areas where linear heat is actively used. In cable trays, which can be applied in just about every commercial or industrial facility, we see linear heat providing early detection for overloading of primary cables. These are typically large gauge, heavy copper conductors, carrying extreme electrical loads, overheating and fire are both very real concerns. And the example they need to heat is reversed above. And in some cases direct contact with the potential hazard, the event of a fire or overheating having detection capabilities this close to the hazard enhances your early warning system. Because of the unique shape and design, we can bring the linear heat detection as close to the areas being protected as needed or even wanted. I also want to note the manner in which the detector is installed due to the nature and construction of linear heat. You must maintain a minimum bend rate as of two and a half inches. Bends tighter than this run. The risk of compromising the integrity of the heat sensitive polymers in the construction. In this example, we see sweeping arcs traverse in the cable tray, which can be installed in either vertical or horizontal runs.

It's required to support the linear heat detector every five feet. The protector our company offers an assortment of approved fasteners and splicing devices to facilitate installation for both standard and special applications. Approved fasteners that generally designed to lightly clamp the detector, which enables a tension to be applied progressively. This method is better than arrangements, which apply a high tensile load at the end of each run or clamp and compress the sensor so tightly that the inner insulation becomes damaged. To ensure a trouble-free installation only factory approved fasteners should be used use of non-approved fasteners may physically damage the detector thereby causing false alarms, or in some cases void the detectors warranty. Shown here are some examples of common accessories used when mountain to cable trays, each clip is designed or chosen to accommodate a different material thickness in a wide range of applications, such as cable trays, storage racks, and even ceiling joists.

In our next slide, we see here, a great example of the HPC two clip being utilized on a steel. Another common application within the power gen market is conveyors and coal fired power plants. Conveyors are used extensively. Some of the common issues seen here are bearing failures and belt slippage, both of which could cause overheating and potential sparking in the presence of coal dust. Designated as a classified hazard, the potential for fire is obviously much greater. Again, we're looking at proximity detection because we want to be as close as possible to these areas to detect and react as quickly as possible.

In some cases the conveyors are covered with a metal hood in these areas, we can provide detection not only below the areas of the bearings and belts, but also above the materials being moved. In these areas, however, access to connection points to support the linear heat are limited to accommodate long spans like this. You had the option of having the linear heat detector coupled with a messenger wire. Installing the messenger detector requires anchor bolts and turnbuckles to maintain the tension of the support cable and eyeballs to provide additional stability. As opposed to supporting the detector every five feet, you can now spread the supports every 25 feet instructions on the proper equipment and installation are readily available. And here we see an example of the versatility, again, of linear heat detection, in confined areas, electrical compartments can become very cramped and very crowded and heat up very quickly.

With the unique design and capabilities of linear heat detection, we can fish the cable in and around the apparatus and provide early proximity detection in the event of an overheat or fire. In transformer applications, we see linear heat being installed directly to the deluge system. In most cases, the linear heat detection will act as a pre action or pre alarm to initiate the alarm sequence. This is considered an integral aspect of the sprinkler operation and should be located as close to the sprinkler heads as possible. In addition, or in place of installation on the deluge pipes, millennia heat detector can be applied directly to the transformer for early detection of overheating. Here, we illustrate the proper techniques to properly apply the detector. As you'll notice, not want to make any penetrations or complete circle around the transformer. Rather we work with the appropriate cable time mounds that can be adhered directly to the surface of the transformer with an industrial adhesive.

We recommend sicoflex 291 cooling towers can be a soupy and murky mess when an operation, these wooden structures withstand years of exposure when they shut down from maintenance is when the concerns are the highest one dried. These structures quickly turn into a potential hazard. And in most cases we see linear heat detection being applied in several areas, including around the fan motor, the gearbox and down into the structure itself. Again, the primary objective is proximity detection to the primary equipment and due to environmental challenges in these areas, we recommend that there be no splices anywhere in these applications. As you can see from these images, the environmental challenges, these structures posts our XDR jacket is a teflon derivative as well suited for a wide range of environments, including chemicals, oils, and even solvents. We also recommend stainless steel hardware be used throughout these facilities. And here's an illustration of some of these installation accessories. Here we have our OHS clip coupled with an RMC three L bracket, both made from stainless steel, which will ensure reliable support without the concern of corrosion

Fixed and floating roof tanks are another common application and one that we've seen significant growth in recent years, both domestically and internationally. Fixed roof storage facilities as depicted here are fairly direct. These are considered classified hazards and need to be installed in accordance with proper guidelines. The use of intrinsic safety barriers and appropriately rated components is crucial. Once these guidelines are met, the rest of the installation is relatively straightforward. As you can see from the illustrations linear heat detection is applied around the perimeter of the storage tank and around the relief valve. The end of line resistor shown at the top of the tank can also be positioned to make annual tests more convenient. The beauty aspect of linear is it simplicity in commissioning and annual testing per NFPA guidelines. Linear heat detection is classified as a non-restorable fixed temperature device as such all that is required to commission or test the system is to short the detector at the end line.

As long as the system can register an alarm. When the detector shorts, you know, you have a fully active detection system. With CTI, this test can actually be taken one step further and an actual heat test can be performed without damaging the detector. This is done through the available test probe, which will short out the detector and register the ambient conditions on the interface module. Heat can then be applied to the test probe to induce an actual heat event, which will run the module as an alarm condition and initiate the alarm sequence. Word of warning though, please be sure to disengage any relays tied to the suppression system to avoid any costly messes.
In addition to fixed roof tanks, we also see a lot of floating roof tanks, as well as fixed floating roof tanks. In a floating roof tank, the roof forms the seal around the inner wall will rise and lower with the level of the material that contains the linear detector is installed in much the same way as a fixed roof with a few exceptions. As you can see here, the detector is positioned just above the rim seal and around the perimeter of the floating roof. Like the cooling tower application, it's recommended to use support hardware that will withstand the expected environments, whether it be the cold and snow of the North or the heat and intense UV in the desert. Connections from the feet cable to the detection zone are achieved through a specially designed retractable cable that can accommodate both PHSC and CTI detectors and extend up to 99 feet. We've been through a few iterations of this design and finally arrived at the MS-3091T you see here, this is an extremely durable and resilient cable well-suited for some of the harshest conditions. The design was also enhanced to accommodate both PHSC and CTI detectors, which simplifies your options. Please consult the factory for additional details.

One of the most popular applications for linear heat are warehouse storage and industrial freezers. In these facilities. Linear heat is typically a component of the pre action system. In freezers, it's the primary releasing mechanism for filling a dry pipe system. When installing Farine rack detection, the detector should be positioned in the flu space at the same level or alternating levels with the sprinkler pipe. Typically, and as I've mentioned before, it would be recommended that the detector be fixed directly to the sprinkler if possible and permitted in your jurisdiction. However, in a manually operated and active store storage facility, the interact sprinklers take an incredible amount of abuse. This is the one area we recommend keeping the detector off to sprinkler pipes and as far out of harm's way as possible with this level of exposure, it's not a matter of if, but when the detector will be compromised. Again, as a digital contact device, the PHSC series does not have the ability to distinguish between heat and physical damage, which is why CTI should be considered in these types of applications. Providing the ability to know the temperature at the spot of the fault will avoid costly alarms.

Of course, this is specific to interact detection. At the ceiling level, the opportunity for damage is greatly reduced. In this area it would be advisable to follow the sprinkler pipes and attached directly if at all possible and permitted. To do so we recommend double loop pipe straps as shown here. These provide your installers, the ability to cinch the cable tie directly to the pipe securely without compromising the detector. The first loop serves as your primary anchor to the pipe. Whereas the second loop provides a taught but loose support to the detector to avoid any damage. For interact we have a variety of clips available to accommodate the installation, including our WAW nylon clip, OHS stainless steel clip and our newly introduced JD-1 clip.

We recently introduced the JD-1 clip to provide install is an easier method of supporting and installing linear heat. Most, if not, all of the supports offered are currently closed loop format. These have been effective accessories for a great many years, but sometimes problematic when making repairs. To do so requires removal of the clip and then the detector then reinstalling. The JD one design resembles a J slot with an open top and a slightly narrowed opening. The open top allows for quick installation and removal of the detector without the need to remove or replace the clips, saving you both time and money.
Another great application of linear heat detection is aircraft hangers and well suited for any of the detection devices offered, including fiber-optic. Due to the volatile nature of these facilities and the various fuels and chemicals present a foam suppression system is required. At the ceiling level linear heat provides the pre action to initiate the foam delivery and is a more economical offering when commissioning and testing are considered. Imagine the number of spot heat detectors required in a hanger that can accommodate several commercial or passenger aircraft based on listed spacing and ceiling heights numbers grow into the thousands. Now consider the process needed to maintain these individual detectors on an annual basis, great work, if you can get it. But if you're looking for a quicker, more economical solution for both you, your team and your customers, then you need to consider linear heat. As opposed to hundreds, if not thousands of individual detectors, large facility can be zoned and have the end of line resistor brought to a convenient location for testing. What you're seeing here is an image of a regional hanger in Massachusetts with 6,000 linear feet of detection broken into three zones. As you can see, that is required to test this system is a six foot ladder and about 15 minutes. We've even included an optional test button to make things even more convenient. In these facilities, false alarms are a major issue and were false alarm discrimination is a huge benefit, both CTI and fiber optic can provide these features to ensure worry free installation.

We see water curtains being employed throughout airports as well. Passenger terminals are typically designed with an overhang to provide shelter and storage for vehicles and equipment. They're also designed with a lot of glass to provide views out onto the tarmac. Being directly below the passenger boarding area requires safety measures are in place to keep windows in the terminal from imploding during a fire. Water curtains are just one of the life safety measures employed. In these structures, the potential for fire is most prevalent in the area below the overhang. In this image, we see linear heat being applied directly above the area, along the lower ledge at the terminal and utilizing a messenger detector to span the distance and providing a great transition around the corner. Again our two and a half inch bend radius is crucial in maintaining the integrity of the detector. Taking the time to assure a smooth transition around these bends will nsure reliable service. In the event of a fire, the linear heat will act as a pre action to initiate the water curtain located above the glass section, keeping the glass cooled during the event.

Road tunnels are a great application for any of the linear heat technologies we currently offer. Where the detector is typically positioned above the travel lanes, they're high enough up out of the way the false alarms should not be concerned. And it's well-suited for the extended runs we typically see. However, some of the tunnels we see internationally, can be as long as seven miles plus. In a facility this large fiber optic likely presents the most effective and versatile tool available. As we discussed earlier, fiber optic is an active detection system reporting real-time temperature conditions throughout its length. The beauty of having this real time information is invaluable when determining the location and the direction of a fire. Picture if you will, being able to tie the real-time data into your HVAC system or your CCTV system, or both. As ambient conditions begin to rise, decrease traffic, the HVAC system can automatically kick on to open vents and increase circulation. In the case of a fire, the CCTV cameras are programmed to pick up the event, providing operators in the control room, the ability to see what type of event is occurring. Is it a car fire, a truck fire hauling wood, or is it a truck hauling chemicals? Where's the fire located, in what direction is it traveling? With all this vital information that can be then reported to the fire department, they know exactly what to expect and the best direction to take, to address the situation.

We've all read the stories of a construction project or renovation that suddenly caught fire. There are a number of reasons for the causes, hot works improper disposal of cigarette butts, or even cooking lunch in a non-designated area, believe it or not. In many of these cases, an active alarm panel is onsite, but the smoke alarms and sprinkler system are taken offline to avoid false alarms. This leaves the contractors and facility owners with the responsibility to provide 24 hour Firewatch. Here in the Northeast and specifically in the Boston area, linear heat has become the default for a wide range of production projects throughout the region. These include schools, hospitals, parking garages, as well as commercial construction with the unique design of linear heat contractors are able to provide continuous detection without the need for Firewatch. Utilizing CTI avoids false alarms associated with accidentally hitting the detector and will only initiate under heat conditions.
Here we see an image taken from one of the more prominent colleges in the Boston area. They adopted linear heat a few years back as their primary detection method during the renovation of one of their dormitories. They have since gone on to include this in all their renovation projects. The detector is installed down the hallway and in and out of the rooms, providing the coverage they need to safeguard the facility while the other systems have been disengaged. When you look at projects like Notredame and the losses, they incurred both financially and emotionally, considering the importance of the building know that there are solutions that help mitigate these situations. Firewatch is great but it's costly and linear heat works 24 hours, four hours a day and never takes a day off.

Next up, we have solar panels. Solar panels are a great resource of energy. It's clean and activated by the greatest natural resource we have available the sun. However, a couple of facts remain. They can catch fire. We seen reports of this almost daily. And in most cases the only way of knowing you have a fire is if someone driving by happens to report it beyond that they're out of sight, out of mind. We see a growing concern, both from building owners and underwriters on the best methods to address this concern. This point, you can probably guess what I'm going to say. I'm going to say it anyways. Linear heat. Again, we're looking at a great way to explore the versatility of linear heat and some of the more unique applications. By running linear heat at the upper lower sections of these panels, you can provide the early detection to avoid costly and potentially catastrophic situations from occurring.

We employ CTTI on the panels, installed on our roof and have seen a few installations where the system alerted them to a small fire and dial directly to the fire apartment avoiding further damage. This is just a small sampling of some of the more common applications we see. It as a no way representative of the broader scope where it can be deployed. Some of the more unique applications we see include iconic towers up in Canada, railroad Trestles, interstitial spaces, historic covered bridges, which we just did a profile story on if you're on LinkedIn or Facebook, uh, as well as religious institutions and the list goes on. If there's one takeaway, I'd like you to gain from our time. I may have mentioned this once or twice, it's the unique versatility of this device to address some of the most challenging applications you may encounter. I want to thank you for your participation today. I hope the information we provided was informative. I look forward to any questions you may have. And my name is Gary Paul. It's been my pleasure.

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