Apollo Series 65 Ionisation Smoke Detector.
The sensing part of the detector consists of two chambers - an open, outer chamber and a semi-sealed reference chamber within. Mounted in the reference chamber is a low activity radioactive foil of Americium 241 which enables current to flow between the inner and outer chambers when the detector is powered up.
As smoke enters the detector, it causes a reduction of the current flow in the outer chamber and hence an increase in voltage measured at the junction between the two chambers. The voltage increase is monitored by the electronic circuitry which triggers the detector into the alarm state at a preset threshold.
An externally visible red LED lights up when the detector changes to alarm state.
An integrating ionisation detector, suitable for use in areas where transient levels of smoke may be expected, is also available.
Series 65 incorporates well-proven sensing technologies, together with advances in materials and electronics technology, including an IC based on that used in XP95 analogue addressable detectors. Having a wide operating voltage of 9-33V, the Series 65 detectors can be integrated into security systems, when used with a relay base.
Ionisation detectors have some sensitivity to air movement (wind). The extent to which the analogue value will change depends on the wind speed and on the orientation of the detector relative to the wind direction. Relatively small changes in wind direction can cause significant changes in analogue value.
For wind speeds up to 1m/s (200ft/min) the change in analogue value will not exceed 5 counts. Continuous operation in wind speeds greater than 2m/s (400ft/min) is not recommended. However, wind speeds up to 10m/s (2000ft/min) can be tolerated for short periods and will not under any conditions increase the probability of false alarms.
Supply voltage: 9 to 33V
Average quiescent current at 24V: 28?A
Average quiescent current at 9V: 16?A
Alarm current at 24V: 52mA
Alarm current at 9V: 17mA
Alarm indication: Red LED
Normal operating temperature: -20 to +60°C
(no condensation or icing)
Max wind continuous: 10m/s
Remote output (R-)