CTI technology is an enhancement to Digital (PHSC) Linear Heat Detection operation. Where traditional Digital Linear Heat Detectors have a single mode of detection, CTI Digital Linear Heat Detectors add a second mode of detection. This second mode of detection utilizes the thermo-electric effect to measure the temperature at the short circuited point of the detector to confirm a true alarm condition exists.

CTI Digital Linear Heat Detectors are constructed of a twisted pair of dissimilar metal spring conductors coated with a thermoplastic coating designed to soften at a specific temperature. An initiating device circuit monitors a length of this detector installed in the area to be protected.

When a short occurs at a point along the detector’s length, the initiating device circuit of the CTM-530 Interface Module detects the short and then automatically switches to a thermocouple measurement mode. The shorted portion of the detector forms a thermocouple junction and its temperature can be measured. The thermocouple measurement represents the current temperature of the shorted portion of the detector. If the short is below the pre-set alarm threshold for the installed detector, a short fault is reported instead of an alarm condition. If the short is above the pre-set alarm threshold for the installed detector an alarm condition is reported immediately.