Nittan EVC-P Photoelectrical Optical Smoke Detector

Nittan EVC-P Photoelectrical Optical Smoke Detector with 375 Ohm Resistor

Using a simple but effective technique, the EVC-P Optical Detector incorporates a chamber housing an Infra-Red (IR) LED light and a photodiode light detector set at an obtuse angle preventing it from seeing the light. When smoke enters the chamber the light bounces off the smoke particles and strikes the photodiode, causing it to generate an alarm condition when a set threshold value is met.

The EVC-P Optical Detector is therefore more sensitive to larger smoke particles which tend to be caused by smouldering fires rather than fast flaming fires.

Operation:

The smoke chamber of the EVC-P is constructed so that light cannot enter from outside, but smoke can pass through the chamber slots. The EVC-P utilises the light scatter sensing principle. The LED pulses every 8 seconds to maintain a low monitoring current. A quick charge time (20 seconds) is also achieved. The detector incorporates an alarm verification function which requires two successive pulses before an alarm is given.

The interval between the first and second pulse is automatically reduced to four seconds after the first alarm level is monitored. The detector design provides strong immunity to air velocities, contamination and RF interference. The geometry of the smoke chamber and optics support assembly is designed to give the best possible signal to noise ratio, resulting in excellent response characteristics.

Key Features:

• Omniview 360° LED
• Internal Alarm Current Limiting Resistor
• Wide Operational Voltage Range (12v-32v)
• Optical Detector