About this item
The Alarm Lock Trilogy T3 DL3500CR is a high-security electronic digital mortise lock with classroom function, 300 user codes, 40,000-event audit trail, 500 scheduled events, and weatherproof construction. If you searched "alarm lock dl3500", "trilogy mortise lock", "alarm lock mortise lock", "t3 lock", or "trilogy dl3500" - this is the product.
Why Mortise vs Cylindrical: The First Decision
Every buyer arriving from "alarm lock mortise lock" or "trilogy mortise lock" is choosing between two fundamentally different lock body formats. No competitor page for the DL3500CR explains this.
Cylindrical locks (DL2700, DL3200): Mount in a bored cylindrical hole through the door. The latch and lever mechanism are contained in a compact cylinder format. Retrofits standard cylindrical prep doors (most hollow metal and wood commercial doors). Easier to install, lower cost, but the mechanism is externally mounted on the door face.
Mortise locks (DL3500CR - this listing): Mount in a deep rectangular mortise pocket cut into the door edge. The entire lock case is embedded flush inside the door. The door edge shows only the faceplate and latchbolt. The mechanism is stronger - the steel case is anchored inside solid door material on all sides rather than held by two through-bolts on the door face. For high-traffic, high-security, or institutional applications where physical attack resistance matters, mortise is the correct specification.
The DL3500CR mortise case meets BHMA specifications for Grade 1 and is UL listed to the 10C Positive Pressure Specification. Installs on the standard ANSI 115.1 mortise prep modified with additional through-bolt holes.
"CR" Suffix: Classroom Function Decoded
The DL3500 ships in two functions:
DL3500CR (this listing) - Classroom function: The outside lever is normally rigid - it does not retract the latch unless a valid code is entered or the key cylinder is used. Inside lever is always active for instant egress. This is ANSI classroom function: key or code grants outside access, inside lever is always free. The 1-3/8-inch mortise cylinder is supplied with a straight cam for classroom function. The latch is 3/4-inch stainless steel with a deadlocking latch - the auxiliary deadlatch pin locks the latch against loiding or case-knife entry when the door is closed.
DL3500DB - Deadbolt function: Adds a 1-inch throw stainless steel deadbolt in addition to the latchbolt. The deadbolt can be projected from outside with the key or from inside with the turn-piece. Cylinder is supplied with cloverleaf cam for deadbolt function. Specify DL3500DB when the opening requires deadbolt security in addition to access control.
"T3 Lock": What T3 Means for This Product
If you searched "t3 lock" - the T3 tier is Alarm Lock's designation for the advanced audit trail and schedule-capable Trilogy locks. The T3 includes the DL3200 (cylindrical, no special function), DL3500CR (mortise, classroom), DL3500DB (mortise, deadbolt), DL4100 (cylindrical, privacy/lockdown), and DL4500 (mortise, privacy). T3 features that distinguish it from T2:
40,000-event audit trail with time/date/user stamp. 500 scheduled events with real-time clock. PC programming via DL-Windows. Data Transfer Module support. Programmable relay. Keypad lockout after failed attempts. These are the features that make the Trilogy T3 the specification for schools, healthcare, government, and any facility with compliance, liability, or security investigation requirements.
The T2 tier (DL2700) has none of these - 100 codes, no trail, no schedules. Choose T3 when you need to know who entered and when, or when access schedules must be automated.
"Trilogy Mortise Lock" Applications: Where the DL3500CR Is Specified
The classroom function mortise lock is the predominant specification in the following application types:
K-12 and higher education: Every classroom, lab, office, and conference room. The classroom function keeps the door lockable from outside without a key when set for code control, while maintaining instant egress for occupants. A 40,000-entry audit trail keeps a detailed record of who accessed each room, making it a powerful tool for both security investigations and day-to-day administrative accountability.
Healthcare: Medication rooms, equipment storage, private consultation rooms, staff areas. The mortise case provides superior physical attack resistance vs cylindrical for secure medical storage.
Government and institutional facilities: File rooms, records storage, secure access corridors, utility rooms. The 500 event schedules automate access windows without manual intervention.
300 Users, 40,000 Audit Trail, 500 Schedules
300 user codes: 3 to 6 digit PINs. Code hierarchy: master, manager, supervisor, and basic user. One-time entry service code for temporary access. Manageable by keypad or PC.
40,000-event audit trail: Every authorized entry (code, date, time, user), unauthorized code attempt, keypad lockout, program mode change, and schedule event is logged. Real-time clock accurate to 1 second. Exportable via AL-DTMIII data module, AL-PCI2 PC cable, or on-site printable via AL-IR1 infrared printer.
500 scheduled events: Automatic lock/unlock events by daily, weekly, or holiday schedule. Real-time clock manages the schedule without manual intervention. Holiday schedules prevent auto-unlock on scheduled holidays.
Programmable Form C Relay: Security System Integration
The DL3500CR includes a programmable Form C relay output. This relay can be configured to energize when selected events occur - triggering a CCTV camera to record on entry, activating a door alarm on unauthorized access, controlling lighting, sending a signal to an ambush alarm (a signal that looks like normal door operation but covertly alerts security), or integrating with building management systems. This is the feature that turns a standalone digital lock into part of a broader integrated security system.
Handing: Right or Left, Field Reversible
Unlike the cylindrical DL3200 which is non-handed, the DL3500CR mortise lock is handed. Right-hand (DL3500CRR) and left-hand (DL3500CRL) versions are specified in order. If reverse handling is required after installation, the lock is field reversible without replacing the lock body. Confirm door handing before ordering to specify the correct suffix - CRR for right hand, CRL for left hand.
Specifications
Model: Alarm Lock Trilogy T3 DL3500CR
Series: Trilogy T3 High-Security Electronic Digital Mortise Lock
Function: Classroom (CR) - outside lever key/code controlled, inside always egress
Deadbolt Version: DL3500DB - adds 1" throw deadbolt with cloverleaf cam cylinder
Finish: US26D satin chrome (also US3, US5, US26, US10B)
Grade: BHMA Grade 1 - steelcase lock body
User Codes: 300 - master, manager, supervisor, basic user, one-time service
Audit Trail: 40,000 events - time/date/user stamped, real-time clock 1-second accuracy
Scheduled Events: 500 (holiday schedule capable)
Programming: Keypad / AL-PCI2 + DL-Windows / AL-DTMIII module
Relay: Programmable Form C - CCTV, alarm, ambush, lighting, building management
Latchbolt: 3/4" stainless steel, deadlocking, UL listed, 3-hour fire rated
Cylinder: 1-3/8" mortise cylinder included - straight cam (classroom); accepts 1-3/8" to 1-1/2"
Door Thickness: 1-3/4" standard; 1-3/8" to 1-7/8"
Backset: 2-3/4"
Handing: Right or Left hand, field reversible (specify CRR or CRL)
Prep: Standard ANSI 115.1 mortise prep, modified
Power: 5 AA battery pak, 80,000 cycles
Weatherproof: Yes - -20°F to +151°F
Compliances: BHMA Grade 1, UL 10C, FCC certified, ADA compliant.
American Locksets has stocked Alarm Lock Trilogy mortise locks since 2001.
Trusted Since 2001
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