Adding Electric Latch Retraction With ACSI’s New Motor-Driven ELR Kit

Jan. 2, 2014
We install the new ACSI 1550K-MDV Motor Drive Electric Latch Retraction Kit onto a Von Duprin XP99 Series Rim Panic Device that incorporates the patented two-piece latchbolt.

Architectural Control Systems Inc. (ACSI) has introduced the 1550K-MD Motor Driven Electric Latch Retraction (ELR) Kits for push bar equipped exit devices. ACSI ELR's are designed to retract the push bar, putting the exit device into the dogged condition, with the latch either retracted or disengaged. The 1550K-MD Kits can provide momentary or maintained operation (electrically dogged).

ACSI Motor Driven Electric Latch Retraction Kits incorporate a screw drive mechanism to unlock the exit device, permitting free egress and access. Using a high speed motor in place of a solenoid makes it possible to provide similar operational times, while significantly reducing the sound that can occur when the push bar is retracted.

The ACSI ELR Kit is installed onto the exit device base plate with motor's screw driven mechanism connected at the rear of the assembly mechanism. When the ELR is powered, the screw drive retracts the base plate assembly mechanism, placing the exit device into the unlocked condition.

To power the ACSI Motor Driven Electric Latch Retraction Kits require a 24VDC 1Amp minimum, filtered and regulated power supply. The current requirement for the ELR is one Amp maximum inrush and 400mA maximum holding current for electronic dogging.

To bring power to the ELR, an electric hinge can transfer power from the jamb to the door. Power to the device is through non-polarized leads, eliminating the possibility of short circuiting the electronics.

UL Listed ACSI 1550K-MDs are for use on fire rated and panic exit devices. To meet fire rated applications, the exit device must relock when power to the ELR is removed. This means when power is removed, the motor must automatically reverse operation permitting the push bar and latch to return to the locked condition. Locksmiths can install ACSI Motor Driven Electric Latch Retraction Kits, maintaining the UL Listing of a fire rated exit device.

Important: Before installing an Electric Latch Retraction Kit into an exit device, make certain the door, door closer and exit device are in proper adjustment and properly operate.

For this article, we will install a ACSI 1550K-MDV Motor Drive Electric Latch Retraction Kit into a Von Duprin XP99 Series Rim Panic Device that incorporates the patented two piece latchbolt. The ACSI 1550K-MDV Motor Drive Electric Latch Retraction Kit will also operate the Von Duprin 98/99 Series and the 33A and 35A Series Exit Devices. The 99 Series and XP99 Series Exit Devices have the grooved mechanism cases.

Note: When installing the ACSI ELR onto a Von Duprin 98/99, the dogging mechanism must first be removed.

The 1550K-MDV Kit is mounted onto the Von Duprin XP99 exit device baseplate, replacing the mechanical dogging mechanism on a panic device. The kit installs onto the baseplate using the two dogging mechanism mounting holes, eliminating the need to drill any holes. The motor driven Connecting Link incorporates two hook-like arms that attach to the baseplate's mechanism. When the ELR is powered, both the latch and the push bar are retracted.

Patented Von Duprin XP98 and XP99 models have a two piece pivoting latchbolt and deadlatch mechanism that attains 90 degree strike to latchbolt contact when subjected to an attack. The XP design delivers 2000+ pounds static load force resistance against unauthorized access. This configuration helps prevent unauthorized entry by resisting repeated attacks. The two-piece pivoting latchbolt design requires 25 percent  less pressure on push bar to release the latchbolt on doors with pre-load.

The XP98/XP99 center case operates differently from the 98/99 Series Exit Devices. When the door is closed and the latch bolt is in the locked condition, pressing the push bar releases the blocking mechanism, permitting the latchbolt to pivot over the roller strike, as the door is swung open. Unlike conventional exit devices, the XP latchbolt does not retract when the push bar is pressed. The blocking mechanism remains in the released condition until the door is closed and the deadlatch mechanism has retracted. When the blocking mechanism engages, the latchbolt becomes locked.

To install the ACSI Motor Driven Electric Latch Retraction Kit, the Von Duprin XP99 exit device must be removed from the door. Remove the end cap and the center case cover to gain access to the mounting screws. After the mounting screws are removed, place the device onto a solid surface to remove the center case, baseplate assembly and the dogging mechanism in order to install the 1550K-MDV Kit.

Begin by removing the two center case mounting screws and the center case cover bracket. Slide the center case with attached baseplate assembly out of the mechanism case.

Use a punch to fix the two rivets securing the dogging mechanism. The rivets will spin freely when a bit contacts them. Once rigid, use a 3/16" drill bit to remove the upper lip of the two rivets and then punch out the remaining portions.

Unscrew the two Philips Head Screws from the 1550K-MDV Kit motor bracket tabs. These are the mounting screws. The cutout in the Connecting Link is designed to slide over and entrap the push bar guide rivet. To accomplish this, the Connecting Link must be on an angle, pushing against the spring at the front end of the push bar guide. With forward and downward pressure, the Connecting Link will entrap the guide rivet on each side.

Once trapped, pull back on the ELR and slide the two motor bracket tabs beneath the baseplate assembly. Just start the two screws through the baseplate into bracket tabs. If the screws are tightened, the baseplate and the motor bracket will probably not align with grooves in the mechanism case, making it difficult to slide the baseplate assembly into the mechanism case.

Place the push bar onto the baseplate and slide baseplate first into the mechanism case. Make sure the push bar is within the case.

Position the center case bracket and install the two bolts securing the bracket to the mechanism case.

Tighten the two motor bracket mounting screws.

With the exit device on its side, test the electric latch retraction. Important: Do not test with the baseplate laying flat.

The 1550K-MDV circuit board is equipped with three on-board diagnostic LED lights. Green is power; yellow is sensor and red is error. Depending upon which LEDs illuminate, ACSI provides a chart for understanding operation. When power is provided, the green LED on the circuit board illuminates. When the push bar retracts to the pressed position, the yellow LED on the circuit board illuminates.

Install the exit device onto the door, leaving the cover plate off and test the electronic operation. Make sure the electric latch retraction operation must not exceed the mechanical operation. ACSI recommends that the electric operation be adjusted to 1/16" less than mechanical operation. This will avoid possibly damaging the exit device.

An adjustment screw is located at the back of the 24VDC motor assembly. Rotating the adjustment screw clockwise increases the amount of latch retraction. Rotating the adjustment screw counterclockwise decreases the amount of latch retraction.

Once the ACSI 1550K-MDV is operational, finish installing the cover plate, end cap components and the center case cover. Test the operation several more times with the door closed.

The 1550K-MD Electric Latch Retraction Kits have been tested to more than 500,000 cycles. ACSI has conducted a rod pull test using a 1550K-MDV installed into a surface vertical rod Von Duprin 98/99 exit device. The kit was capable of lifting 10.25 pounds after the 1550K-MD completed more than 500,000 cycles.

Field or factory installed Electric Latch Retraction Kits are available for the following exit device models:

  • Corbin Russwin ED4000/ED5000 Series
  • DORMA 9000 Series
  • Falcon 24/25 Series
  • Hager 4500/4600 Series
  • PDQ 6200 Series
  • Stanley Commercial Hardware QED100/QED300 Series
  • Von Duprin 33A/35A 98/99
  • Yale 7000 Series.

Factory installed only Electric Latch Retraction is available for Adams Rite 3000/8000 Series. 

Electric Latch Retraction Kits will be available for:

  • Arrow 1000/3000/4000 Series
  • Design Hardware 1000 Series
  • Dor-O-Matic 1690/1790 Series
  • First Choice 3600/3700 Series
  • Jackson 20 Series
  • Precision 2000/5000 Series
  • Sargent 80 Series  

For more information, contact your local locksmith distributor or Architectural Control Systems Inc., at 2720 Clark Avenue, St. Louis, MO. 63103 Telephone 800-753-5558 Local Phone 314-652-5588, Web Site: