The Detex 102665 is the OEM Magnet Replacement Kit for the Detex EAX-300 Series and EAX-500 Series exit device alarm systems, documented in the official Detex EAX-300 and EAX-500 installation and parts catalogs. The 102665 provides the replacement magnet assembly for the door position detection circuit in both series. It is an individually serviceable component - when the magnet fails or loses effectiveness, this kit restores the door monitoring function without replacing the entire device.

The companion standard magnet kit for the EAX series is the 102656-1. Both 102665 and 102656-1 are magnet-related components for the EAX alarm system - confirm which specific magnet component the installed device requires before ordering.

What the Detex EAX-300 and EAX-500 Series Are

The EAX-300 is Detex's compact door prop and chime exit alarm device, designed to sound an alarm when a secured door is held open beyond a set time period. It is battery-powered (9V, part number PP-5567 or equivalent), uses a 0.313 inch by 0.715 inch mortise cylinder for arming and disarming, and operates on the same key logic as other Detex alarm devices: counterclockwise rotation = Armed, clockwise rotation = Disarmed.

The EAX-300 can be installed on either side of the door and is suited for emergency exit doors, restricted access doors, and secondary exit applications where a compact, battery-operated alarm is the correct specification. For technical support, Detex directs installers to call 1-800-729-3839 and select option 2.

The EAX-500 is the companion series to the EAX-300, sharing the same magnet replacement component (102665). Both series use the same door position detection architecture - magnet mounted on the door, sensor mounted on the frame - and both are serviced with the same 102665 magnet replacement kit. The physical format and output specifications differ between the 300 and 500 series, but the magnet detection system is consistent across both.

How the Magnet Works in the EAX-300/500 Exit Alarm System

The EAX-300 and EAX-500 alarm systems use a magnet-and-sensor pair to detect door position. The magnet mounts on the door edge. A paired sensor (a reed switch or Hall effect sensor mounted in the device body on the door frame side) detects the presence of the magnet when the door is in the closed position.

When the door is closed, the magnet is aligned with the sensor. The sensor is activated, holding the alarm circuit in the secure/armed state. When the door opens - whether by authorized use or unauthorized entry - the magnet moves away from the sensor. The sensor deactivates, and the alarm triggers. If the door is held open beyond the configured time threshold, the alarm continues to sound until the door is closed and the sensor re-detects the magnet, or the device is manually disarmed with the key.

The magnet is the moving half of this detection pair. It is subject to physical forces every time the door opens and closes - impact against the frame, vibration, temperature cycling on exterior doors, and potential contact with moisture or chemicals. These conditions degrade the magnet over time. A weakened magnet may not trigger the sensor reliably at the correct close distance, which produces false alarm events when the door is closed. A physically damaged magnet - cracked or missing - eliminates door monitoring entirely. The 102665 Magnet Replacement Kit addresses both conditions.

Detex EAX-300 Series Parts: 102665 in Context

The Detex EAX-300 parts catalog lists several individually serviceable field-replacement components. Alongside the 102665 magnet replacement kit, the EAX-300 series parts include:

102655 = Cam Assembly Kit - the cam mechanism inside the device that interfaces with the mortise cylinder for arming and disarming.

102656-1 = Standard Magnet Kit - the companion magnet kit. The 102665 and 102656-1 are both magnet-related components in the EAX parts catalog. The specific application of each is confirmed in the EAX-300 and EAX-500 installation documentation.

103779 = Cylinder Nut Socket - used with a standard Yale cam configuration in the EAX device.

102633 = Hardware Kit - includes the Keystop (102688) and mounting hardware for field installation.

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