Creating a Constant Alarm as long as Photo Beam is Broken

Using a Photo-Beam System as a Constant Alarm Reminder

A common request from customers is for a system which will stay in constant alarm mode once triggered. Most driveway alarm systems will only send one alert signal per vehicle entrance, than recycle and wait for the next vehicle to send an alert. This is perfect for most residential and even commercial applications; however some settings require a system where they would like the alarm to sound continuously as long as a vehicle is parked in the monitored area.

With magnetic probe systems, only moving vehicles will trigger an alarm. So once a vehicle has parked it becomes “invisible” to the metal sensing probe. The best solution we have found for these situations where the client requires a constant alarm signal as long as a vehicle is in the monitored area is using the Optex Photo Beams. The Optex Photo Beams feature both Normally Open and Normally Closed output relays. As long as the photo beam between the sensors is broken the output relays will remain “latched” in their alarm positions, this is a great systems for a lot of commercial and industrial applications where hard wiring in a buzzer, siren, strobe light etc. which is constantly signaling is desired.

In large or noisy installation areas a momentary alarm signal is often not enough to notify the appropriate personnel that a vehicle has entered the area, installing a photo beam system with the latching relay will ensure that as long as a vehicle is parked or located in the monitored area the alarm will continue to sound, flash etc. until the vehicle either moves or the alarm is acknowledged or deactivated.

Weigh scales, lanes with blind corners, or other areas where the client would like to know if a vehicle is in the monitored area are perfect applications for these types of systems. The system can also be modified to transmit a continuous alarm signal wirelessly if that is required, please contact us for this type of custom build.