Electric Latch Retraction (ELR): ELR can be provided with a new exit device or possibly retrofitted into an existing exit device. Electric latch retraction is also referred to as electric dogging, since when the latch retraction is energized, the door is not latched, just as if the exit device had been mechanically dogged. It is able to swing freely so individuals can pass through in either direction. There are EL devices for rim, mortise, concealed vertical rod and surface mount vertical rod exit devices, both for fire rated and non-fire rated exit devices.
Rim Strike: These are mounted on the door frame between the head of the exit device and the original ‘keeper’ mounted on the frame. When in an unlocked state, the door behaves as if it was dogged. These strikes are intended for use on single swinging doors, or pairs of doors with a mullion.
Electrified Mortise Lock: If you are working with a mortise exit device, the mortise lock can be replaced or the existing mortise lock can be modified for electrical operation. Electrification will enable the outside trim to be used for authorized access.
Electrified Trim: This is used for any type of exit device, where there is a lever on the exterior of the door. When the appropriate signal is applied to the lever trim, the lever can be actuated and the exit device’s latch will momentarily retract.
Vertical rod devices can be concealed rods or surface mounted rods. For some applications you can use only the upper rods (upper rods only).
Bottom rods are prohibited on manual doors as per Americans with Disabilities Act (ADA) Accessibility Guidelines because they create an obstruction on the face of the door on the push side.
Since our doors had a door operator on one of the leafs, the owner interpreted the ADA requirement that the opening was not a manual door but an automated opening; anyone approaching the could push the handicapped button and not make any contact with the door at all. However, it is always best to confer with the LAHJ for approval.
Concealed vertical rods inside the body of the door are a more attractive solution. Because it is necessary to install latches into the bottom of the door, and there is limited space between the bottom of the door and the finished floor, removing the door will be necessary for a retrofit installation.
Surface Vertical Rods are relatively easy to retrofit on existing doors because you can install them without removing the doors from the frame.
If the door has a handicapped door operator, electrical control of the exit device must be considered because the door operator cannot open the door if the latch is holding the door. Therefore, if the handicapped operator is expected to work during times when the doors are latched, either a rim strike or electric latch retraction must be used.
If the customer specifies that the handicapped buttons work only when the doors are dogged down, the door operators will theoretically not be actuated while the doors are latched. In practice, this does not always work out the way the client says it will and people will try to use the handicapped buttons, while the doors are latched.
Door operators react differently to being triggered to open locked doors. As part of the ANSI specification for low energy operators, they are designed to sense an obstruction as small as 15 pounds and stop immediately.
Some operators will automatically shut down if they sense an obstruction when triggered from a closed position, requiring the door operator be powered down and the power up sequence be performed.
Some operators will eventually burn out a clutch if repeatedly triggered while the door is latched. This happened to a nearby nursing home where clients would try to leave the premises after hours when the door had been locked, and it resulted in a damaged motor/clutch assembly, and a very costly repair for the nursing home.
Some manufacturers stipulate that repeated triggering of an operator on a locked door invalidates the warranty.
Part of the project would involve interfacing the existing handicapped pushplates with the new system so that the entry handicapped plate would only operate if the doors were unlocked or, when locked, a valid credential was would trigger the operator. If the doors were electrically dogged, pressing the entry handicapped button would activate the door operator. The egress handicapped plate would always work.
The principle national standard for low energy doors is the American National Standards Institute’s Standard for Power Assist and Low Energy Power Operated Doors, known as “ANSI A156.19.”