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Series 8500

Gemini Locking System


  • UL Listed Gemini mortise lock – no special door prep
  • UL Listed Gemini operator located in the frame
  • Ability to work with a wide range of mortise lock manufacturers:
    • Arrow
    • Corbin Russwin
    • Schlage
  • Fail Safe (Power Lock)
    • Outside trim is locked when power is applied and unlocked when power is removed (storeroom function when energized). Lockset will unlock in the event of a power failure (passage function).
  • Fail Secure (Power Unlock)
    • Outside trim is unlocked when power is applied and locked when power is removed. Lockset will lock in the event of a power failure.
  • 24VDC or 24VAC/DC
  • When key cylinders are provided in the locks, the latch bolt may be momentarily retracted with key even though electrically locked. Note: Locks that are electrically unlocked may not be locked via the key cylinder.
  • Easy installation: Gemini operator fits easily into 2” face frames. Only one wiring termination.
  • Optional quick connect cable
  • Continuous duty rated
  • Heavy-duty stainless steel housing
  • Security monitoring available
  • Interface with life-safety systems

ACSI Series 8500 Gemini Locking Systems provide safety and security for stairtower doors or controlled areas where both locking and latching are required. The Gemini system allows remote electric locking or unlocking while conforming to life-safety codes. The system consists of two components: a Gemini modified mortise lockset and a frame mounted Gemini operator.

8500Gemini operator with standard ANSI strikeplate


8500FGemini operator with oversized strikeplate




Gemini mortar guard 15”