Fermax Lock Release 540AD-S Max

Fermax 28201 Electric Lock Release 540AD-S Max (12Vdc Automatic Fail Secure)

The Fermax 28201 is an electric lock release mechanism designed for standard door frames, providing automatic re-locking and fail-secure operation powered by 12V DC. Its designation details are: 540 series standard body, AD operation (Automatic Fail Secure DC), S type standard shield, and MAX adjustable latch. Note the absence of the second a in AD, indicating this model does *not* have a manual override lever.

The 540 body fits common timber and metal frame preparations. The key feature is the AD operation: Automatic Fail Secure for DC voltage. The lock is secure (locked) when unpowered. Applying a 12V DC pulse momentarily unlocks it. Like other Automatic types, it only stays unlocked until the door physically opens and closes again, at which point it automatically re-locks mechanically. This ensures the door is secured after each authorised entry, even if not manually locked. The S shield is the standard grey flush plate (approx 25x160mm), and MAX provides the adjustable jaw for alignment.

This model is ideal for applications where guaranteed re-locking after entry and fail-secure operation are paramount, and where a manual override function is not needed or desired for security reasons. Its 12V DC operation suits many access control systems and specific Fermax DC intercom configurations. Remember to ensure the door closer is effective enough to properly re-latch the door for the automatic function to work reliably.

Features

• Standard Duty Electric Lock Release (540 Series Body)
• Operation: AD - Automatic Fail Secure DC (No Manual Override)
• Voltage: 12V DC (Implied by D, confirm voltage if needed, often multi-voltage capable or specific 12VDC needed)
• Shield: S Type Standard Flush Shield (approx 25mm x 160mm) - Grey
• Latch: MAX Adjustable Jaw (+/- 4mm adjustment)
• Reversible design (Left/Right DIN)
• Symmetrical body
• Automatic re-locking function after door cycle
• No manual override lever
• Suitable for standard timber and metal door frames

Technical Specifications

• Manufacturer: Fermax
• Model Reference: 28201 (Type 540AD-S MAX)
• Operation Mode: Automatic Fail Secure DC
• Input Voltage: 12V DC (Verify if multi-voltage capable from datasheet)
• Current Consumption (12V DC): Check datasheet
• Body Series: 540 (Standard)
• Shield Type: S Type Flush Plate (Grey, approx 25x160mm)
• Latch: MAX Adjustable
• Holding Force: Refer to Fermax datasheet

Dimensions

• Body Dimensions (540 approx): 75mm x 21mm (height x width) - depth varies.
• S Shield Dimensions (approx): 160mm x 25mm (height x width).