Concealed Door Loop
The tamper resistant Concealed Door Loop (CDSL) is designed to slide into the cavity within the door and/or jamb when the door is closed, concealing the conduit. As the door is opened, the armored conduit extends between the door and jamb. The CDL conduit is long enough to support up to a 180-degree door swing.
The Command Access patented Concealed Door Loop makes uses of custom stainless steel, .268” inner diameter flexible armored conduit that can be installed directly into the door edge and jamb, or into most configurations of continuous hinges and butt hinges. Because the CDL is limited only by its inner diameter of more than one-quarter inch, it has the capability to accommodate larger gauged wires. This large opening will accommodate more than eight 18 AWG wires, more than sufficient to power a locking mechanism, controls and switches. In addition, electronic cabling (CAT5, etc.) can be run through the Concealed Door Loop.
For doors equipped with 3/4” offset pivots, Command Access has longer CDL that is fixed at the door and extends into the jamb cavity. Like the standard Concealed Door Loop, the ¾” offset pivot version can be installed anywhere along the door edge and the jamb.
In a CDL-equipped opening, as the door opens, the custom ¼” diameter flexible armored conduit is pulled from door side into the opening. As the door is closed, the CDL slides into the frame completely concealing itself. The Concealed Door Loop for ¾” offset pivots can be installed into entrances whose door swing is up to 105 degrees.
Door Loops/Armored Door Cords
Surface-mounted door loop/armored door cord is the simplest, most economical and most vulnerable solution for transferring low voltage power from the jamb into the door. A door loop is comprised of two connectors and a flexible metal conduit (usually between 12” and 36”). One end of the door loop is mounted onto the jamb. The other end is mounted onto the face of the door. The length of the conduit depends upon the type of hinge and the desired degree of opening. The conduit can be cut using a hack saw to the desired length.
The diameter of the flexible conduit can vary with most having an approximate 5mm inner diameter. Most door cords will accommodate up to twelve 28 AWG. Unlike electric hinges, door loops do not come with pre-installed wire.
The main variation for a door loop is the method of attaching the conduit to the door and jamb. Some models are secured using screws and some use the “screwless” design. The “screwless” door loops do not require any screws to attach them to the door and frame as they snap into place.
Power Transfers are designed to provide low voltage power or pneumatic latch retraction from the jamb into the hinge side of the door edge. A Power Transfer is normally installed between the upper two butt hinges. When the door is closed, the Power Transfer is a concealed, tamper resistant method to provide power to a door-mounted lock mechanism, control and/or switch.
The Von Duprin Electric Power Transfer (EPT) has two stamped steel housings with an extendable rigid conduit mechanism that must be mortised in the door edge and the jamb. The Von Duprin EPT is UL Listed as a Fire Door Accessory and can be used on doors that have up to a 3 hour fire rating. For fire rated openings, the jamb and door cut-outs must be manufactured by the door company.
Note: Von Duprin offers the Pneumatic Control PNT-1 functions with pneumatic latch retraction exit devices. The PNT-1 is dimensionally identical to Von Duprin EPT models.
Some companies offer electric power transfers that have only one housing and a flexible spring steel conduit. An example is the Securitron Square-Cut Electrical Power Transfer (SEPT). The SEPT is mounted into the hinged edge of the door and the connector is attached to the jamb. As the door closes, the flexible spring steel conduit with the connector and spring steel conduit enters into the housing. The SEPT conduit has a ¼” inner diameter.
Deliver total door service by fixing the real problem — worn hinges — and you’ll make more money and also satisfy a customer by fixing their problem for good.
We install a McKinney Continuous Geared Door Hinge onto a narrow stile aluminum glass door and aluminum frame.