How do I operate Magnetic Door Retainers using a fire alarm system without central panel?
Probably the easiest and most straightforward option is to use Ei141, Ei146, Ei161 or Ei166 smoke alarms interconnected. One of the units would be mounted on an Ei128R relay base and all door holders would be wired through this relay base. The door holders used would be the MDH230 model. All units could then be run from a 230V AC feed. The system would operate in the same way as above in that if any of the interconnected alarms sounded, the relay contacts in the Ei128R would switch and consequently the door holders would be switched. The Ei140/Ei160 series alarms do have an internal battery back-up (Ei140 = Alkaline PP3, Ei160 = Rechargeable Lithium) and so the alarms would still sound in the event of a mains failure. However, the MDH230 door holders or the Ei128R relay would not operate without mains power.
