Common Myths About Protectowire Linear Heat Detectors


There are many tips out there about how to best use Protectowire Digital Linear Heat Detectors. However, much of the advice you hear may just be myths. Here are ten of the most common myths debunked:

  1. Protectowire Linear Heat Detector can only be used on Protectowire control panels

False. The electrical characteristics of the Protectowire Linear Heat Detector are compatible with most manufacturers’ control panels and addressable modules.  The system designer should confirm Protectowire Linear Heat Detector compatibility with the panel or module’s manufacturer. The maximum length of each Protectowire Linear Heat Detector zone can be calculated by using the resistance of the conductors.

  1. Protectowire Linear Heat Detector is affected by Electromagnetic Interference (EMI) or Radio Frequency Interference (RFI)

False. The functional operation of Protectowire Linear Heat Detectors is not affected by EMI/RFI.  However, initiating device field wiring can act as a pathway for the transmission of EMI/RFI to associated control equipment.

  1. When determining the design of proper fire protection/detection equipment, Protectowire Digital Linear Heat Detectors should be used in the same way as smoke detectors and can be considered life safety.

True/False. Digital Linear Heat Detectors are typically installed as property protection but in some cases can be used as a life safety device, especially, in residential attics and interstitial spacing. The system designer should always adhere to applicable, local codes and consult the Authority Having Jurisdiction (AHJ) to ensure compliance for each installation.

  1. Protectowire Digital Linear Heat Detectors should not be put into freezers or warehouses because they can cause false alarms if a forklift or machinery physically damages the detector.

False. If the Protectowire Digital Linear Heat Detector is installed correctly on the back of the load beam in-between the flue spaces it is then protected from possible contact with falling objects or machinery. If the possibility of mechanical damage is a concern, we recommend choosing Protectowire Confirmed Temperature Initiation (CTI) Series Detector. This detector is specifically designed to address the issues of physical damage to linear heat detection systems. The CTI Series uses multi-criteria detection to eliminate false alarms and assures only heat activated alarms are reported. Our CTI Series Detector is available in the same jackets, fixed temperature ratings, installation practices, and listed spacing as all Protectowire Digital Linear Heat Detectors.

  1. Fiber Optic Linear Heat Detectors cannot be spliced.

False. Protectowire Fiber Optic Linear Heat Detectors can be fusion spliced. Line loss per fiber optic channel should not exceed 1 db. The fiber optic fusion splicing equipment and persons performing splices must be trained in their use.

  1. After a digital linear heat detector has alarmed (shorted) the entire zone must be completely replaced.

False. Once a Protectowire Linear Heat Detector has alarmed you only need to replace the portion that has been actuated and not the entire run. The shorted section of the digital linear heat detector can be replaced by splicing in a new section of the detector.

  1. You can paint linear heat detectors.

False. Per UL and FM requirements a linear heat detector can never be painted under any circumstances.

  1. All Protectowire Linear Heat Detectors use the same splicing and termination hardware.

False. Protectowire CTI Linear Heat Detectors are constructed using “T” type thermocouple conductors which require all terminations be made via “T” type thermocouple terminals. This is to ensure the temperature measurements made by the CTM-530 Control Module will provide short circuit discrimination as accurately as possible. We provide a full line of splice terminals and junction boxes specifically designed for compatibility with our CTI Linear Heat Detectors.

  1. You need to have an alarm point location meter in order to determine an actuated (shorted) hot spot.

False. By knowing the resistance value of the Protectowire Digital Linear Heat Detector you can calculate the location of an actuated hot spot with an ohm meter.

  1. The CTI Linear Heat Detector is compatible with other initiating devices.

False. Unlike standard Protectowire Digital Linear Heat Detector which is compatible with any normally open switch type initiating devices, CTI Series Linear Heat Detectors are not. The CTI Series Linear Heat Detectors must be monitored by a Protectowire CTM-530 Interface Module. The CTM-530 interface module is compatible with any fire alarm control panel or addressable module.



Best Practices for Installing Linear Heat Detection

This video will provide you with best practices for installing Protectowire Linear Heat Detection products.

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