Feb. 1, 2008
The gate lock/remote access controller system provides access control for this single-gate dock area by using known hardware and making use of existing proximity card equipped identification badges.

I was invited to observe the installation of the Securitron GL1-based access control system onto a secured delivery dock sliding gate that was located in an industrial protected enclosure. The one-sided dock was equipped with an approximate ten-foot long by seven-foot-tall iron mesh faced sliding gate that ran along an upper guide. Heavy duty iron mesh fencing surrounded the gate, from floor to ceiling, preventing unauthorized access into the dock area. Prior to electrification, access through this gate was controlled using a heavy duty padlock with a restricted keyway.

The Securitron GL1 Gate Lock was chosen because of its heavy duty design and because it requires a separate controller. This gate lock is a weather resistant electromechanical lock mechanism designed for swing and sliding gate applications that require electronically controlled access. The GL1 Gate Lock is designed for interior and exterior applications. The GL1 swivel latch assembly is rated at 2,000 pounds holding force. The field-convertible GL1 requires 12 or 24 Volts DC, and operates as Fail Safe or Fail Secured (locked). The Gate Lock is designed to be installed onto the secured side of the gate. The mounting bracket can be welded or bolted onto a base. The strike assembly has bolt holes and comes with mounting hardware. The strike assembly can also be welded.

The Securitron Gate Lock strike is a spring loaded rod assembly that enters the latch opening in order to lock the gate. The swivel type strike assembly provides up to +/- 1/2” tolerance from the centerline of the lock to the centerline of the strike. This allows for changes as simple as the sliding gate's rubber wheels wearing over time or changes in closing angles due to settling or earth movement.

The Gate Lock and the rod strike assembly can be mounted vertically or horizontally to accommodate the specific application. For this application, a welded base with blocking against the fence was installed to accommodate the Gate Lock. The Gate Lock was bolted and welded onto the base. The strike assembly was bolted then welded onto the facing edge of the sliding gate.

For this installation, the Gate Lock was wired Fail Secured. In the event of power loss, it would remain locked. The purpose of this system is to prevent unauthorized persons from entering the dock area. In an emergency, the GL1 is equipped with a latch release that is located beneath the cover. A cam lock secures the cover onto the chassis. For convenience, the cam lock can be mounted onto either side of the cover. For this installation, the cam lock was mounted onto the right side, which opened onto the dock.

The Securitron GL1 has a built-in status sensing feature that indicates when the gate is open or closed. This feature enables someone in a remote location to know the condition of the gate lock.


Gaining access onto the delivery dock through the gate is controlled by the Alarm Lock PDK3000 Digital Access Keypad with proximity reader. This 12V/24V 12-button keypad and proximity reader is approximately the size of a duplex outlet. The PDK3000 has the capacity of up to 2,000 User Codes, real time clock and a 40,000-event audit trail that is time/date-stamped. The weatherproof keypad with proximity reader is equipped with two 10Amp relays. The PDK3000 accepts most HID proximity cards and fobs.

The Alarm Lock PDK3000 has three options for access: proximity card or fob only, code only or both proximity and code. For this application, access will be through proximity cards only as most employees of the facility have proximity card name badges and only a limited number of personnel will need access.

The PDK3000 Digital Access Keypad with proximity reader is fingertip or PC programmable. The real time clock with time zone adjustments has capability of up to 500 scheduled or holiday events. The unit has the ability to report removal or vandalizing attempts by date and time via an alarm system. Proximity card data can be added to PDK3000 by uploading from the keypad, using the AL-PRE or entering directly from computer using DL-Windows software. The Alarm Lock AL-PRE proximity card reader/enroller enrolls proximity cards and key fobs into DL-Windows Software.

Three sides of the dock area are connected to buildings; a cement block building is on the fourth side. The front of this block wall building aligns with the sliding gate. The right side and the back of the block wall building are also attached to the dock. The rear of the door and the other side are additional buildings.

The dock is covered by tin roofing.

The Alarm Lock PDK3000 was installed onto the front wall of the block building approximately four feet from the opening side of the gate. The block wall building is at ground level and the dock is approximately three feet above ground level.


The power source is a surface-mounted 120VAC conduit attached to the block wall. Power was run from a duplex outlet to the SARGENT Power Supply. This enabled the power supply to be located out of sight at the rear of the block wall building. The SARGENT #3510 power supply was installed onto the block wall at approximately five feet above the concrete floor.

The #3510 power supply is UL Listed for Class II circuitry. This 24VDC power supply outputs 1.8Amps of filtered and regulated power. The enclosure is approximately one foot square. The power supply itself was used as a template to locate the three mounting holes. Wall anchors were used to secure the SARGENT #3510 onto the wall.


To unlock the gate from within the dock area, a Securitron PB2E Push Button was installed in a single gang box beneath the power supply. The PB2E is a two inch square, momentary, green lens Single Pole Double Throw (SPDT) Push Button.

Note: Although the dock area is covered, it is not protected from the elements. For this type of application, Securitron recommends using a Securitron PB Series Push Button that is designed for exterior as well as interior applications.

The pushbutton can be used to unlock the gate lock from within the dock, permitting egress and access. It was wired into the timer function in the Alarm Lock PDK3000. This way when the push button is pressed, the gate lock will be powered and unlock for a time-adjustable period.

The time required for the installation was approximately three hours, which included bringing in a welder and electrician to provide 120VAC for the SARGENT power supply. The gate lock mounting bracket was supplied by the welder and manufactured prior to the installation. See the wiring diagram for installation details.

The gate lock/remote access controller system provides access control for this single-gate dock area by using known hardware and making use of existing proximity card equipped identification badges. By taking advantage of an existing identification technology and having a number of installed Alarm Lock access control products, this facility saved money by using existing proximity cards, and saved time since the learning curve for the DPK3000 is minimal.

For more information, contact your local locksmith wholesaler or:

ALARM LOCK SYSTEMS, Inc., 345 Bayview Avenue , Amityville , NY 11701 . Telephone: 800-252-5625. Fax: 631-789-3383. Web Site:

SARGENT LOCK, 100 Sargent Drive , New Haven , CT 06511 . Telephone: 800-727-5477. Fax: 203-821-5793. Web site:

SECURITRON MAGNALOCK CORP., 550 Vista Blvd. Sparks , NV 89434 . Telephone: 775-355-5625 or 800-MAGLOCK. Fax: 775-355-5633. Website: