Leaders in
Latch Retraction

ELECTRIC LATCH RETRACTION (ELR)

Since 2012, when SDC launched QuietDuo™ – the first Motorized ELR Kits to convert mechanical exit devices – we’ve been “quietly” leading in electric latch retraction (ELR) upgrades for access control. This includes retrofit solutions for most brands of exit devices as well as innovative SDC exit devices & mortise locksets with factory-installed ELR and automatic door operators with a built-in 1 Amp+ power supply to power them.

The Purpose of Electric Latch Retraction

ELR was originally designed for entrance and exit doors with panic or fire exit hardware to provide remote unlocking, remote dogging, access control or automatic door operator functionality. When energized an electric solenoid would retract the exit device latch and pull the pushpad on most devices into the dogged (depressed) position enabling momentary or sustained push and pull operation of the door. The latch retraction mechanism may be activated by an access control, remote control device or building automation system.

Solenoid ELR vs. Motorized ELR

Electric solenoids have been used for decades in electronic locking devices like electric bolt locks to electrically operate the deadbolt for either failsafe or failsecure operation and in exit devices to electrically retract the latchbolt. During periods of extended use, solenoids can become quite heated and noticeably sluggish. With advancements in electric motor technology, the use of a motorized electric latch retraction device provides several advantages over solenoids including lower current draw, quieter operation and greater durability over time.

Why SDC’s Motorized Electric Latch Retraction

From retrofit ELR field kits to exit devices and mortise locksets, all SDC ELR products use the same motorized technology to provide both latch retraction and dogging. Additionally, all are grade 1 and UL listed. Because of their low current draw, SDC ELR products can be powered with the built-in 1 Amp+ power supply that come standard in SDC’s AUTO series low energy operators. This eliminates the need for a separate power supply! SDC’s LR100 series retrofit ELR kits not only eliminate the need for costly replacements of existing exit devices, but also deliver cost savings on installation of select exit device brands without removing the device from the door.