The low energy operator has gained importance as a result of Americans with Disabilities Act (ADA) requirements for commercial facilities to provide access and egress for the physically disabled. Low energy door operators open the door when a lock, touch pad or similar product is activated. Unlike high energy automatic swinging door operators that make use of sensors, the low energy versions do not require guard rails, safety mats or a certified installer.
The three-hour fire rated Detex Low Energy Automatic Door Operator AO19 Series meets American National Standard requirements for Power Assist and Low Energy Power Operated Doors (ANSI/BHMA A156.19), the requirements of the American Disabilities Act and UL 325 and UL10C. It is designed for medium to high traffic applications operating doors up to 250 lbs.
The Detex AO19 Series is a motor and gearbox with clockspring design power door operator. Extending from the gearbox is the clockspring and the spindle shaft. An arm attached to the spindle shaft pushes or pulls the door to the open and closed positions when the spindle rotates. As the DC powered motor opens the door, the clockspring winds up. When the door is opened, the motor stays engaged to keep the door held open. As the door closes, the motor slows the rotational forces of the clockspring, resulting in a slow, smooth closing cycle.
To control the opening, hold open and closing cycles, the motor receives varying amounts of amperage. The amount of amperage is controlled by a potentiometer (like a light dimmer switch). The more amperage, the faster the door will swing open. The Detex AO19 can be adjusted to open a door much faster than the minimum ANSI requirement of four seconds for a low energy operator.
The less amperage, the slower the door will swing during the opening cycle as rotational resistance applied by the clockspring increases. A minimum amount of amperage is required to maintain the door in the open position. If no power is provided, the door will close because the clockspring’s rotational pressure is forcing the gears to rotate in the closing direction.
Because the gearbox, clockspring and motor low energy door operation involves significant amounts of restive forces for controllably smooth operation, the Detex AO19 was designed with a one-inch diameter spindle shaft and a heavy duty hypoid gear equipped gearbox. The spindle shaft has 19 1/8”-thick teeth around the circumference insuring that neither the spindle nor the arm assembly teeth will strip. The motor is custom for the AO19 in order to provide the specific revolutions per minute and torque required.
Speed of the opening and closing operations as well as the open time are adjustable. There are minimum times specified in ANSI/BHMA A156.19. These include a minimum of four seconds opening time, a five-second hold open time and a 4.5-second closing time (3 seconds from 90 degrees to 10 and 1.5 seconds from 10 degrees to fully closed. The size and weight of the door can affect the opening and closing times.
However, these are only the minimum times. Each application’s times are determined by the abilities and disabilities of the persons using the doorway. To accommodate the diversity of needs, the hold open time is adjustable from 0 to 60 seconds.
I was invited to observe the installation of the Detex AO19 Low Energy Automatic Door Operator and a Detex Exit Device with Latch Retraction onto a non-public, double door entry used by employees of a large facility. The inactive door is equipped with two flush bolts. The active door can be opened to a maximum of 110 degrees. The employees are the plumbers, electricians, HVAC, etc. The individuals who keep the facility operating use this door more than 600 times a day.
This exterior doorway with outswinging three-foot doors leads into a very large multi-function room. The room contains stock for some of the trades as well as a machine shop, locker room, etc. From this room, there are smaller specialized application rooms and hallways leading to other areas and exit doors within the building.
Often, employees enter and leave through this door throughout the day carrying armloads of supplies. Some of the supplies are bulky and cumbersome including fluorescent lights, pipe, hardware and fire extinguishers. Having an operator installed makes access and egress less difficult.
For a low energy operator to work in conjunction with a locking mechanism, i.e. exit device, mortise or cylindrical lock, the operator must have the ability to unlock the locking mechanism prior to swinging open the door.
To simplify the ordering and installation process, Detex offers Automatic Operated Door (AOD) EasyKits for doors that require a low energy operator with an exit device. Each AOD EasyKit includes an Advantex Latch Retraction-equipped exit device, the AO19 low energy door operator with a built-in, pre-wired 24VDC filtered and regulated power supply with logic controller for electric latch retraction. This power supply provides sufficient amperage to power receiver for push plates. For this installation, they installed two wireless push plates. The receiver came pre-wired and installed in the AO19.
AOD EasyKits are available in a number of configurations to accommodate door width as well as the different exit device configurations. For this installation, the Detex part number is AODx10ERx1S. This EasyKit contains a three-foot AO19, a rim exit device with electric retraction power supply and logic controller, an electrified hinge and two wireless square push plates and receiver.
To install this EasyKit, 120VAC is required and two wires must be run between the exit device and the on-board power supply and logic controller. For a clean installation and no hanging wires that can be damaged or broken, the center hinge was replaced with an electrified hinge to provide the power transfer.
For access during non-work hours, a function 08 lock cylinder equipped trim was installed onto the exterior side of the door. The trim is secured directly to the exit device mounting plate. This key operated, lever trim can provide access during a power failure or when the operator is offline.
Exterior walls of the building are concrete. To ensure smooth operation of the door swing, the hinges were replaced. Electricians ran 120VAC wiring in flexible metal conduit to a wall mounted duplex outlet above the hinge side of the door.
Because the metal jamb was not concrete filled nor did not line-up with the wall face, a third concrete anchor was added between the two anchor holes in the hanger plate. The hanger plate secures the operator to the wall and the third concrete anchor provides additional reinforcement.
To provide an aligned surface to mate with the jamb, a piece of aluminum was cut to accommodate the shape of the wall in order to install the low energy operator hanger bracket flush with the doorjamb.
The hanger bracket is mounted to the interior wall for this push application door operator. The hanger plate is located IN five-eighths of an inch from the outside edge of the hinge jamb and down 1-1/2” from the upper edge of the header jamb. This way the lower mounting screws in the hanger plate thread into the header jamb. Use a level to make sure the header plate is square.
The mounting holes in the header plate are counter-sunk 3/16” diameter. Three holes were drilled for the 3/8” drop in anchors using 1-1/2” long #3 Phillips Head screws. Four 11/64” diameter holes were drilled into the metal header jamb and tapped for the 12-24 mounting screws. To provide additional protection, blue Loctite® was used on the screws threads for those being installed into the header jamb. The header plate was mounted flush against the header jamb and the wall.
The header plate has two angled mounting tracks. The operator has mating surfaces. The operator can be lifted and slid down into place by one person. Push down onto the unit to ensure it is level. Install the screws in the top corners.
Because of a wall running perpendicular to the left side of the doorway, the 120VAC had to be routed through the top of the case instead of the side opening. A hole was drilled for the wiring to the left of the gearbox. Flexible metal conduit was run from the duplex box to the case. The wire was run and connected to the duplex outlet.
At this point the arm is installed. The difference between the arm assembly of this low power operator and a door closer is the foot (shoe) shaft is cut to size. To determine the length of this shaft, the operator is powered and the switch is switched to the “Hold Open” position. The spindle will rotate to and remain at the open position. The arm is then placed onto the spindle arm so the shaft is at a 50 to 60-degree angle (for a three-foot door) through the door opening. Attach the arm in this position. Test the operation to be certain the arm returns to this angle several times.
With the foot installed 16 inches from the door hinge edge, mark the position of the arm receptacle onto the shaft. The position should be almost to the rear of the receptacle arm shaft opening. Cut the rod to length. Install. Test the operation of the AO19.
Next, install Detex Advantex® rim exit device with electric latch retraction. Electric latch retraction is necessary for the exit device to retract the latch before the power door operator begins to open the door. The AO19 has an electric lock switch that delays the door from opening until the exit device, lock, electric strike or magnetic lock unlocks permitting the door to swing.
For this portion of the installation, the black and red wire was run from the AO19 into the jamb and out the wire hole for the Detex electrified hinge, part number EWH8-626 The Electrified Hinge replaced the existing center hinge on the active door. This 4-1/2” x 4-1/2” x 5 knuckle hinges contains eight wires. For this installation, the red and black 20 gauge wires connected the rim exit device to the power supply electric lock switch. The hinge wires for this side are longer to connect directly to the exit device.
The remote control receiver was attached to the rear of the case using Velcro. Four screw covers were removed from the push plates and set to match the receiver and the dip switches were set.
The Advantex and the trim were installed at the height of the cylindrical lock. A small piece of stainless steel was used to cover the exposed portion of cylindrical locks’ cross bore opening. Because the inactive door has a 16-gauge steel parting strip on the inside, there was no need to install a separate strike plate.
The operation of the AO19 and Advantex exit device were tested. The default values of adjustments were sufficient for the initial operation of the door. For handicapped applications, it is recommended that someone in a wheel chair operate the AO19 to be certain the times are sufficient for safe access and egress.
The Detex AO19 has a number of adjustments for the operation of the door, located on the controller. These include speed adjustments:
Closing adjustment of 2-30 seconds (default is 5 seconds)
Latch adjustment of 1-3 seconds (default is 1.5 seconds)
Open adjustment of 2-20 seconds (default is 5 seconds)
The Hold Open adjustment under the timer area is identified as Activation. The adjustment range is 1-60 seconds with the default of five seconds.
The opening and closing force adjustment is from five to fifteen pounds with the default at ten pounds. Consult your local authority having jurisdiction for your area’s requirements.
When installing the push plates, provide sufficient time for the person to operate the plate and then enter or leave without the door closing on them. For this installation, the two wireless push plates were installed onto the interior and exterior walls adjacent to the door. Because this is a left hand door, the exterior push plate was installed onto the left side of the opening. The interior push plate was installed onto the left side about fifteen feet back from the doorway on the perpendicular wall.
The provided signage was installed at 50” +/- 12” above the finished floor on each side of the door.
The AO19 is designed to accommodate a 13-inch reveal when installed onto a push application. Contact factory for a reveal that is greater than 13 inches.
The Detex AO19 has a number of standard features that are not applicable to this installation. These features include:
Adjustable delayed activations when installed in multiple (sequenced) vestibule doorways or mantraps.
Adjustable door reversal feature for an obstruction of five pounds or greater. The door stops moving and reverses directions. Must be selected.
Push & Go feature activates when door is manually pushed to open. Must be selected. An optional application for the handicapped. An alternative means of access to using push plates.
Power close feature applies additional power in the last few degrees of the latching cycle to aid in the door closing and latching. Must be selected.
For more information, contact your local locksmith distributor or Detex at 830-629-2900, Web Site: www.detex.com.