Latch Retraction Mortise Lock
PWM202HO Power Booster Interface Module
Mortise locks have not been a viable option for access control systems incorporating a door operator where an exit device is not a necessity. The reason: when an electrified mortise lock or trim is activated, it unlocks the lock mechanism. A person must physically rotate the knob or lever to retract the latchbolt, and then the door can be swung open.
To solve this problem, Command Access has introduced the LPM180 Mortise Lock that provides Fail Secure (EU) electric latchbolt retraction. The Grade 1 LPM180 Storeroom function mortise lock body meets the operational cutout dimensions of ANSI A115.1 86 lock prep.
The LPM180 can be operated by retracting the latchbolt electronically, by key outside or lever/knob inside. The outside lever/knob is always rigid. The inside lever is always free for immediate egress.
Latch retraction is accomplished by a powerful solenoid that is built into the case. When the Fail Secure solenoid is powered, the latch retracts, permitting the door operator to swing the door open. Because the latch must retract almost a full ¾”, the solenoid is at a mechanical disadvantage.
For this reason, the LPM180 requires 24VDC with a significant inrush to retract the solenoid armature almost ½”. The large solenoid and inrush is required because to retract the latchbolt, the spring pressure must be overcome. This is more complicated because the retraction cannot be in direct line with the latchbolt.
To provide sufficient power to retract the latchbolt, a patented Command Access PWM202HO power booster interface module is included with the LPM180. The PWM202HO provides two separate functions. The initial firing is a High Output (HO) current surge created by a large capacitor in the PWM202HO in order to start the retraction of the solenoid armature. The surge is approximately 13A for 150-200milliseconds (ms). Once the initial retraction movement begins, a lesser amount of continuous surge power is required for the armature’s retraction. This surge continues for approximately 350ms. More than enough time to complete the ½” retraction required to clear the latchbolt from the strike.
Note: The PWM202HO is polarity sensitive. The two connectors have one-way directionality to insure proper connection.
The PWM202HO circuitry allows for momentary or continuous applications. For continuous “push/pull” applications, once the latchbolt has been retracted, the PWM202HO effectively changes the 24VDC providing approximately three to four volts to the solenoid to maintain latch retraction without overheating the solenoid. In this configuration, the door can remain “dogged” mode continually.
The PWM202HO power booster interface module must be installed within ten feet of the LPM180 mortise lock body to maximize the surge. The module can be installed into the hinge side doorframe. Having the power booster this close to the electric latch retraction mortise lock allows for a longer wire run from the power supply to the mortise lock.
The Command Access LPM180 Mortise Lock comes with three six-foot lengths of 18-2 gauge wire. Two lengths can be combined between the mortise lock and the module. The third six foot length is for connecting the module to the access control system. Each of the lengths has a plug-in connector. According to Command Access, the wire run can be up to seven hundred feet using 18/2 gauge wire between the LPM180 Mortise Lock and the power supply.
The Command Access electrified mortise lock is equipped with an anti-friction, stainless steel latchbolt. The latchbolt is field reversible to accommodate door handing.
No special lock prep is required to install. The LPM180 mortise lock is compatible with the Schlage L9080 mortise lock cutout. The trim is compatible with the L9000 Series. Contact the factory for trim and finish availability.
To ensure proper operation of the LPM180, Command Access requires the use of their power supplies to maintain the three-year warranty.
For more information, contact your local locksmith distributor or Command Access Technologies, Telephone: 888-622-2377. Web Site: www.commandaccess.com.
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