Door Holder Release System

Description and Purpose

Door holders hold hallway doors, elevator barrier doors, and other automatically-closing doors used for fire barriers.

In larger buildings, on routes of heavier travel, management often prop doors open to keep the flow of pedestrian traffic moving. However, these buildings need the safety of being able to seal one area from the other in the event of a fire. This restricts the flow of smoke and toxic gasses that are generated by a fire.

The fire alarm, intrusion, remote control or panic system can integrate magnetic door holders so that in the event of a crisis, the system can release doors so they may automatically close. In addition, the system can integrate door position sensors to verify the closed status of the door after release. The maximum number of doors that can be released by the system depends on the control panel you choose.

Figure 1: Releasing Magnetic Door Holders

Connections and Considerations

The table below refers to the drawing in Figure 1. If you are using this document on line, click the model number in the table below to see more information.

Item	Model No.	Description	Mounting Options	Notes
D	4101SN	Relay: Addressable with zone input		I/O Module
Cs	4939SN	Contact: Surface Mount	Exposed on Door or Window Frame	1.25” gap
O₁₂	AD25624	Power Supply (DC Voltage indicated)	In enclosure (#1451-24)	Selectable 12VDC or 24VDC operation when using XF30 transformer.
V	V-Plex	V-Plex™ Data Bus		Connects to addressable devices, zone input devices and relay modules.
Y	Genesis: 4506	2-wire, 18 AWG, Fire rated, Non-shielded	Use Genesis 1118 for Non-Fire Applications	This part number is an example. See your building and electrical codes for actual jacketing requirements.

Solving Automatic Door Issues

For fire safety reasons, automatic door closures are often installed on doors in busy hallways or stairwells. During times of high traffic, these doors can be held open to allow for uninhibited flow of pedestrian traffic. In the event of a fire, the fire alarm system can release doors that are held open, closing them to reduce the spread of smoke and toxic fumes within the facility. Likewise, in the event of a panic alarm, the panic system can release doors to lock down a facility.

By using door position sensors, the system can sense if a door is held ajar or propped so that facility staff can be notified and promptly clear away props to close and secure the door.