Apollo AlarmSense Integrating Optical Smoke Detector 55000-391APO

Overview

This Apollo detector belongs to the AlarmSense family, a two wire system where the panel both powers and controls the detectors.

It is the integrating version in the range of optical types. It is meant for places where a short burst of smoke is likely to come and go.

How it works

• Light scatter: smoke drifting into the sensing chamber scatters light, and the detector senses that scattered light.
• Pre-set threshold: the detector changes to the alarm state once smoke penetration into the chamber reaches a pre-set threshold.
• Integrating: this means the detector watches the smoke over time instead of acting on one reading, which is how it can discard passing smoke.
• Sampling: it takes a reading once every four seconds.

Where to use it

It suits bedrooms and escape routes. It is designed to IP44, and the humidity limit rules out condensation or icing.

Any detector that senses particles can react to steam, dust or cooking fumes, so kitchens and shower rooms usually need another approach. A delay is a design choice too, so check it with whoever holds the fire strategy for the building.

What the figures mean in practice

• Reset: a maximum reset voltage of 2 V and a reset time of 1 sec matter when matching a detector to its panel.
• Supply interruption: 40 ms is the longest supply break for this detector, which matters on a two wire circuit.
• Alarm current bands: the current changes with voltage, peaking in the 10.5 - 15 V band, so the panel maker's figures matter when working out a zone.
• Test conditions: values are typical at 24 V, 25ºC and 50% RH unless otherwise stated.

Installing it

Polarity insensitive wiring removes one common mistake on a two wire run. Allow for the taller 50 mm height once the head sits in its base.

The nickel plated stainless steel terminals sit behind a white flame-retardant polycarbonate housing, and the LEDs can be seen through 360º, so a lit LED is easy to find during testing.

Planning your system

Start with the panel, because this detector can only be used with purpose designed AlarmSense fire control panels.

The guide to commercial fire alarm systems explains how categories and zones shape a design. Other smoke detectors from the same maker may suit a different kind of system.

Standards and ratings explained

• EN 54-7: the European standard for point smoke detectors. The approvals also include CPR and FG.
• CPR: the Construction Products Regulation 305/2011/EU. It complies with its essential requirements.
• EMC: it complies with the EMC Directive 2014/30/EU when used as described in the maker's instructions.