Lesson 1.2: Electric Door Strikes

⚡ The Logic (Mermaid)

flowchart LR
    CTRL["Access Module
Door Relay COM"]

    CTRL -- "NO
(Power to Unlock)" --> STRIKE["Fail-Secure
Strike"]
    CTRL -- "NC
(Allways Powered)" --> STRIKE_FS["Fail-Safe
Strike"]
    
    STRIKE --> VZ[0V PSU]
	STRIKE_FS --> VZ
	
    PWR["12V PSU"] --> CTRL

Hardware Landmark: Electric Door Strike

!300
Above: A standard Fail-Secure electric strike. Note the locking cam that physically holds the door latch.

🧠 The Concept

Electric strikes are the most common locking device. Fail-Secure (standard) means the door stays locked if power fails. Fail-Safe means it unlocks if power fails (used for fire exits). In Inner Range, you configure the relay on the ILAM or SLAM to match this logic.

🛠️ Hands-on Steps

Identify Strike: Check if the strike is Fail-Safe or Fail-Secure.
Wire Relay: For Fail-Secure, wire to COM and NO. For Fail-Safe, wire to COM and NC.
Diode Protection: Always install a MOV or Diode across the strike to prevent "Back-EMF" from damaging the controller.
Test: Badge a card and listen for the "click" of the strike releasing.

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