BEST LSM303 Electric Mortise L...
IN STOCK (leaves warehouse same day if ordered before 3pm ET)
$1,629.65
PRECISION Precision Hardware Inc (PHI) Latchbolt Monitor Switch, 03 Function Mortise Body LSM303

BEST LSM303 Electric Mortise Lock Latchbolt Monitor Switch with 03 Function

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Model: LSM303 626 RHR
$1,629.65
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In Stock (leaves warehouse same day if ordered before 3pm ET)

$1,629.65
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BEST LSM303 Electric Mortise Lock Latchbolt Monitor Switch with 03 Function

Professional Electric Mortise Lock Monitoring Solution

The BEST LSM303 Electric Mortise Lock Latchbolt Monitor Switch provides precision monitoring for 03 function mortise lock systems. This handed electric mortise lock features SPDT switch technology rated to 2 Amps at 24VDC for reliable latchbolt position monitoring in commercial applications. Engineered for professional-grade performance in demanding access control environments.

Professional Features & Benefits

  • Precision Latchbolt Monitoring: LSM303 and LSM303F models provide accurate latchbolt position feedback for enhanced security system integration.
  • Heavy-Duty Electrical Rating: Switch rated to 2 Amps at 24VDC with SPDT configuration ensures reliable signal transmission for access control systems.
  • 03 Function Design: Specifically engineered for 03 function mortise lock applications providing optimal compatibility and performance.
  • Handed Configuration: Precision handed design ensures proper installation and operation for specific door applications.
  • Commercial-Grade Construction: Built for demanding commercial environments where reliable lock monitoring is essential for security operations.
  • Professional Integration: Designed for seamless integration with access control systems requiring latchbolt position feedback.

Technical Specifications

  • Commercial/Residential: Commercial
  • Department: Door Hardware
  • Lock Type: Electric Mortise
  • Product Category: Mechanical Locks
  • Product Group: Mechanical Locks
  • Product Subgroup: Mortise Locks and Trim
  • Product Type: Mortise Locks
  • Series: LSM303
  • Subcategory: Electric Mortise

Installation & Operation

  1. Verify electrical requirements match available power supply. Confirm 24VDC voltage and current capacity before proceeding.
  2. Disconnect power supply before beginning installation. Follow all applicable electrical codes and safety procedures.
  3. Mount the unit in the specified location ensuring adequate clearance for wiring access, ventilation, and future service requirements.
  4. Route and connect wiring according to manufacturer wiring diagrams. Use appropriate wire gauge and connectors for the application.
  5. Configure operational settings including SPDT switch configuration per application requirements.
  6. Restore power and test all functions including normal operation, latchbolt monitoring feedback, and integration with connected access control systems.
  7. Complete final inspection and document settings. Refer to manufacturer documentation for complete wiring diagrams, programming instructions, and troubleshooting.

Professional Applications

  • Commercial Building Security Systems
  • Access Control Integration
  • Healthcare Facility Monitoring
  • Educational Institution Safety Systems
  • Industrial Facility Security
  • Government and Municipal Buildings
  • Multi-Tenant Commercial Properties

Why Choose BEST Quality?

BEST LSM303 electric mortise lock monitoring switches deliver professional-grade reliability with precision SPDT switch technology rated to 2 Amps at 24VDC. Engineered for demanding commercial applications where dependable latchbolt position monitoring is essential for comprehensive security system operation.

Manufacturer Resources

Precision 2000 Series Catalog

Product Specs

Series:
LSM303
Product Group:
Mechanical Locks
Product Subgroup:
Mortise Locks and Trim
Product Type:
Mortise Locks
Subcategory:
Electric Mortise
Commercial/Residential:
Commercial
Lock Type:
Electric Mortise
Product Category:
Mechanical Locks
Department:
Door Hardware

BEST LSM303 626 RHR – Frequently Asked Questions

1) What does the BEST LSM303 latchbolt monitor switch actually report to an access control panel?
The LSM303 is a latchbolt monitor built into an 03 function mortise lock body. It reports latchbolt position, so the panel sees whether the latch is projected into the strike or retracted, rather than whether the door leaf is closed. Pair it with a door position switch if you also need door-open status. The switch is SPDT, so you can wire either a normally open or normally closed contact off the common.
2) Is the BEST LSM303 handed, and which hands are available?
Handing matters here. The LSM303 is a handed mortise body and is built as Left Hand Reverse or Right Hand Reverse only. Reverse bevel means the door swings out of the room toward you with the hinges on the far side. If your opening is a standard LH or RH inswing, this configuration is the wrong call, so confirm the swing at the opening before you specify.
3) Is there a fire rated version of the LSM303 latchbolt monitor?
Two switch builds are offered: Standard and Fire Rated. The fire rated build is the one to order for a labeled opening, corridor door, or stair door where the lock has to stay in the fire assembly. Order the standard build only for non-labeled openings.
4) What do I have to specify when ordering a BEST LSM303 mortise latchbolt monitor?
Three choices settle the order: handing (Left Hand Reverse or Right Hand Reverse), switch build (Standard or Fire Rated), and finish. Finishes run 605 bright brass, 606 satin brass, 611 bright bronze, 612 satin bronze, 613 satin bronze oil-rubbed, 618 bright nickel, 619 satin nickel, 622 matte black, 625 bright chrome, 626 satin chrome, 629 bright stainless, 630 satin stainless, and 690 statuary dark bronze.
5) If I need latch position monitoring plus electric lock/unlock control of the outside lever in one mortise body, what should I look at instead of the BEST LSM303?
The BEST LSM303 is a latchbolt monitor switch for an 03 function mortise body, with a SPDT switch rated 2 Amps at 24VDC that reports latchbolt position only - it does not electrically control the lever. If the opening also needs the outside lever electrically locked or unlocked, the Schlage L9092EU 03A electric lock/unlock outside lever mortise lock runs on 12/24VDC, is keyed outside with request-to-exit, and is a heavy duty corridor function for 1-3/4 inch doors. Use the LSM303 when monitoring is the requirement and the Schlage when the access control system must actually release the lever.
6) What is the difference between the BEST LSM303 and a motorized electrified mortise lock like the Command Access ML190?
The BEST LSM303 is a latchbolt monitor switch built into an 03 function mortise body - a SPDT switch rated 2 Amps at 24VDC that feeds latchbolt position back to the access control panel. The Command Access ML190 series is a motorized mortise lock with field selectable fail safe or fail secure operation on 24VDC, heavy-duty, storeroom function, meaning the panel drives the lock itself. Both use 24VDC, but one reports and the other actuates.
7) For a fire rated opening, is the BEST LSM303 the right monitor switch or do I need a different lock?
The LSM303 is offered in both a Standard and a Fire Rated latchbolt monitor switch configuration, so a fire door can be monitored with the same part family by specifying the fire rated version. If the fire door also needs the lockset replaced, the Falcon MA101 is a Grade 1 heavy duty mortise passage lock with a fire rating, and the Schlage LEMD-GRW Grade 1 ENGAGE wireless mortise lock carries a 3 hour fire rating.
8) What voltage and current can the LSM303 monitor switch handle?
The switch is rated 2 amps at 24VDC in an SPDT configuration. That is a signal-level contact, so run it into an access control input or a relay board, not directly on a strike or maglock load. Verify your panel's supply is 24VDC before wiring.
9) Do I need a latchbolt monitor or a request-to-exit switch on my mortise lock?
They answer different questions. A latchbolt monitor like the LSM303 tells the panel whether the latch is thrown, which is what you want for a forced-door or secure-status report. A request-to-exit switch signals that someone turned the inside lever to leave, which is what suppresses a forced-door alarm on egress. If you need the egress signal, look at an RX-equipped mortise lock such as the Schlage L9092EU with 03A electric lever trim and RX, which is a 12/24VDC corridor-function mortise lock.
10) I need the lock itself to be electrically controlled, not just monitored. What should I look at instead?
The LSM303 monitors latchbolt position; it does not lock or unlock the door on command. For electrified control, the Command Access ML190 Series is a motorized mortise lock with field selectable fail-safe or fail-secure operation on 24VDC in a storeroom function, and the Schlage L9092EU with 03A electric lever trim runs on 12/24VDC with request-to-exit. Either of those gives you remote control at the lever.
11) Can I add the LSM303 monitor to a mortise lock I already have in the door?
No. The LSM303 is a complete 03 function mortise lock body with the monitor switch built in, not a kit that drops into another manufacturer's case. Replace the existing body with the LSM303 in the matching hand, and reuse the trim and cylinder only if they suit an 03 function body.
12) We want credential-based access at the door rather than monitoring. What mortise locks cover that instead?
The BEST LSM303 is a monitoring switch only - it reports latchbolt position over a 2 Amp 24VDC SPDT contact and carries no reader or keypad. For credential access at the door, the Schlage CO-100 is a Grade 1 standalone electronic mortise lock with a keypad reader in privacy function for 1-3/4 inch doors, the TownSteel FME-2000 is a Grade 1 heavy duty classroom mortise lockset with RFID, and the Dormakaba E-Plex E5086 is a Grade 1 pushbutton and card mortise lock. Those replace the lock; the LSM303 supplements one.
13) Do I need to order the BEST LSM303 handed, and are there mortise locks that avoid handing?
Yes - the LSM303 is a handed switch offered in Left Hand Reverse and Right Hand Reverse, so the door swing has to be confirmed before ordering. If handing is a concern elsewhere on the job, the Falcon MA101 Grade 1 heavy duty mortise passage lock is field reversible, and the Kaba Ilco 185 series mortise deadbolt is supplied with no handing. Those are different products, not substitutes for the monitor switch.
14) Our spec calls for a keyed Grade 1 mortise lockset, not a monitor switch. What fits that?
The BEST LSM303 is a latchbolt monitor switch for an 03 function mortise body and provides position feedback rather than keyed security. For a keyed Grade 1 mortise lockset, the Accentra 8805FL is a Grade 1 storeroom mortise lock with Arcadia lever in the 8800 series, the Cal-Royal NM8080 is a Grade 1 storeroom mortise lockset with an interchangeable core option for 1-3/4 inch doors, and the Corbin Russwin ML2003 is a Grade 1 classroom mortise lockset for 1-3/4 inch doors.
15) Can I use the BEST LSM303 on an aluminum storefront door with a deadlatch?
The LSM303 is a monitor switch for an 03 function mortise lock body in commercial door hardware and depends on that mortise prep. For an aluminum storefront using Adams Rite style deadlatches, the Alarm Lock DL1300NW Trilogy Networx wireless electronic mortise lock is built for Adams Rite deadlatches, and the Dormakaba E-Plex 2066 is a wide stile electronic pushbutton keyless mortise lock. Confirm the existing door prep before choosing between them.
16) Which finish should I pick to match the rest of the doors in my building?
For commercial openings the two common matches are 626 satin chrome and 630 satin stainless steel, and both are offered. Also available: 605, 606, 611, 612, 613, 618, 619, 622 matte black, 625, 629, and 690 statuary dark bronze. Match the BHMA finish number already stamped on your existing hardware rather than matching by eye, since satin chrome and satin stainless read almost identically at a distance but are different alloys.
17) Is the LSM303 rated for commercial traffic, or is it a residential part?
Commercial. The LSM303 is an electric mortise lock body built for commercial access control work, and it is the kind of monitoring hardware used on healthcare, education, government, and multi-tenant openings where the security system needs latch feedback.
18) Is a mortise thumbturn like the Sargent 130KB an alternative to the BEST LSM303?
No. The Sargent 130KB is a standard duty mortise thumbturn for the 8200 series, a mechanical inside trim piece with no electrical function. The BEST LSM303 is an electric latchbolt monitor switch for an 03 function mortise body with a SPDT contact rated 2 Amps at 24VDC wired to an access control system. They address different parts of the opening and neither replaces the other.
19) We are standardizing finishes across a building - how do the BEST LSM303 options compare with other mortise hardware we might specify?
The LSM303 is offered in 13 finishes including 605 bright brass, 606 satin brass, 612 satin bronze, 613 oil-rubbed satin bronze, 619 satin nickel, 622 matte black, 626 satin chrome, 630 satin stainless steel and 690 statuary dark bronze, which covers most commercial finish schedules. Where a matching lockset is needed, the Marks USA 5PDN Grade 1 hospital passage paddleset and the TownSteel MRX-L-01 Grade 1 ligature resistant lever mortise lockset are both supplied in satin stainless steel.
How fast can I get the BEST LSM303 626 RHR delivered?
Most orders ship the same day from our distribution partners, with quick delivery throughout the continental U.S. Need it urgently? Contact Us for expedited shipping options.
Can I return it if it doesn’t work for me?
Yes—ZenSupply offers a hassle-free return policy. If the product isn’t the right fit, reach out to our support team for a return authorization or setup a return by following our return instructions.
Does the BEST LSM303 626 RHR come with a warranty?
Absolutely. The BEST LSM303 626 RHR is backed by a manufacturer’s warranty. For full warranty terms, check the product documentation or Contact Us.
How do I get technical support or installation help for the BEST LSM303 626 RHR?
You can call, text, or email our expert support team for fast answers. We’re here to help with product selection, installation tips, and troubleshooting. Contact Us
Why buy the BEST LSM303 626 RHR from ZenSupply?
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