Wednesday, September 29, 2010

What is the best electrical connection for Emergency drop curtain?

Emergency curtain drop system is essential for poultry house when power failure occur. It will automatically drop the side curtain of your tunnel ventilated closed house and it also help to trigger the alarm to alert worker attentions.

Getting the right electrical connection for the emergency drop curtain system is important.  Some of the common alarm systems use in the tunnel ventilation system are :- 1. Power failure alarm. 2. High room temperature alarm. 3. Fan motor trip alarm. We can have the drop curtain electrical connection in such a way that when the power failure alarm and the high room temperature alarm trigger, it will trigger the emergengy curtain drop system at the same time.

Through our experience, it is recommended to have a second set of back up alarm circuit. It should be DC 12voltage battery power supply with charger. The primary alarm circuit is electrical dependent and the second alarm is wind flow dependent. It can be a simple metal plate hinged on the ceiling level with a limit switch attached next to it. As long as there is a wind flowing in the house the metal plate flows away from the limit switch but when there is no wind flow, the metal plate will drops down and touches the limit switch which in turn trigger the alarm and the emegency curtain drop at the same time.