I have a customer who's requirement involves having a new 70v paging system (Valcom) with multiple zone be overidden at will by a Whelen emergency 70v system. The Whelen system has to be able to take over the speakers and shut out the new system in the event of a emergency broadcast. My main problem is figuring out if it is possible set up two 70v systems that can switch back and forth on some type of relay. I Cant find any equipment that exists that will perform this task. Anybody have any suggestions?

BBTech